ghid bioch struct stom engl 2017-2018...ninhydrin reaction method's principle: ninhydrin reacts...
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"NicolaeTestemitanu"StateUniversityofMedicineandPharmacy
ChairofBiochemistryandClinicalBiochemistry
STRUCTURALBIOCHEMISTRY
PracticalguideforFacultyofDentistrystudents
Student_________________________
Groupnr.______________________
Professor________________________
CHISINAU,2018
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LESSON№1 Data_________________
Introduction.Theimportanceofbiochemistryformedicine.Bioelementsandbiomolecules.Functionalgroupsandtypesofchemicalbondsspecificforbiomolecules
TheInitiallevelofknowledge
1. Chemicalelements.Periodictableofchemicalelements.
Self‐trainingquestionsIssuesfortraining1. Introductiontobiochemistry.Theimportanceofbiochemistryformedicaldisciplines.
Structuralbiochemistryanditsgoals.2. Bioelements ‒ organogenic and minerals. Content and overview of the main
bioelementsthatmakeupthehumanbody.3. Biomolecules.Micromolecules,macromoleculesandcomplexmolecules.4. Functionalgroups.Typesoffunctionalgroupsspecificforbiomolecules.Theirgeneral
properties.5. Typesofchemicalbondsspecificforbiomolecules.Theirgeneralproperties.
Tasksforindividualwork1. Carbon in the unexcited state has the electronic configuration of the outer level
(valencelevel)2s22p2andinthecompoundsitcanhavethedegreeofoxidation+2,but in the excited state it has the electronic configuration 2s12p3. How canschematicallybeshowntheelectrontransition?
2. DrawtheschemeofelectronicinteractionofammoniawithH+ionbydonor‐acceptor
mechanism.
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3. Placethemoleculeintothespecificcolumnofthetableaccordingtothechemicalbondpresentinthemolecule–CO2,H2O,HCl,NH4,O2,N2,Cl2,CH4,NaCl,NaH2PO4,Na2CO3,protein,DNA.
Covalentnon‐polar Covalentpolar Ionic Hydrogen
Self‐assessmenttests:
1.Whichofthefunctionalgroupsdeterminestheacidicpropertiesofbiomolecules?
a)–SH; b)–NH2; c)–CONH2; d)–COOH; e)–OH2.Whichofthefunctionalgroupsdeterminesbasicpropertiesofbiomolecules?
a)–SH; b)–NH2; c)–CONH2; d)–COOH; e)–OH3.Whichtypeofbondisproducedbetweentheatomsofthesamekindorbetweentheatomswithsimilarelectronegativity?
a) covalentpolar;b) hydrophobic;
c) covalentnon‐polar;d) donor‐acceptor;
e) coordinative
4.Whichtypeofbondisproducedbetweendifferentatomsofnon‐metallicelementshavingdifferentelectronegativity?
a) covalentpolar;b) ionic;
c) covalentnon‐polar;d) donor‐acceptor;
e) coordinative
5.Whatkindofchemicalbondisformedasaresultofammoniainteractionwithhydrogencations?
a) covalentpolar;b) ionic;
c) covalentnon‐polar;d) donor‐acceptor;
e) hydrogenbond
6.SelectthecorrectstatementsregardingVanderWaalsforces:
a) relativelyweakforcesofattractionbetweenneutralmolecules;b) relativelyweakforcesofrejectionbetweenneutralmolecules;c) forcesofstrongattractionbetweenneutralmolecules;d) forcesthatstabilizethepolarcovalentbonds;e) forcesthatstabilizethenon‐polarcovalentbonds.
7.Whichpairsofatomsandfunctionalgroupswillformionicbonds?
a) CandN;b) NH2andH+;
c) COO‐andNH3+;d) Cl‐andNa+;
e) COO‐andNH2.
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8.Hydrogenbondisformedbetween:a) apartiallypositivelychargedhydrogenatomandpartiallynegativelychargedO,NorSb) apartiallynegativelychargedhydrogenatomandpartiallypositivelychargedO,NorSc) apositivelychargedhydrogenionandpartiallynegativelychargedO,NorSd) apartiallypositivelychargedhydrogenatomandpartiallynegativelychargedO,NorPe) apositivelychargedhydrogenionandnegativelychargedOorN.
LESSON№2 Data_________________
Waterstructure,physicalproperties,ionization,ionicproductandpH.Buffersolutions
Experiment1.PreparationofbuffersolutionsTask.Prepare20mlof0.1mol/laceticbufferwithpH=5.24using0.1mol/lCH3COOHand0.1mol/lCH3COONasolutions.Dissociationconstantofaceticacidis3∙10‐5.Background. Buffer solutions can be prepared in two ways: 1) solutions of eachcomponentsarepreparedseparatelyandafteraremixedinone,2.)onecomponentofthebuffer solution is dissolved in water and another component is added to the obtainedsolution.ItisimportanttoknowthevalueofbuffersolutionpKaandtocalculatesolutionpHusingHenderson–Hasselbalchequation.Procedure1. Calculate howmanymilliliters of 0.1 mol/l CH3COONa and 0.1mol/l CH3COOH are
necessarytomixtoobtain20ml0.1mol/lofaceticbufferwithpH=5.24.2. CalculatetheratioofcomponentsusingtheequationрН=рКа+lg[salt]/[acid].3. Fromtheratioofbuffermixturecomponents results that it shouldcontainXpartsof
saltandYofacid, i.e. all4parts.So, thesaltvolume isequal to (20•x) :4,andacidvolumeisequalto(20•y):4.
4. CheckthepHofthepreparedbuffersolutionusinguniversalindicatorpaperstripsorthepH‐meter.
5. Thereportmustcontainthecalculationoftheratioofthemixturebuffercomponents.6. Fillinthetable:
Theratioofthemixturebuffercomponents
AcidVaandsaltVsvalues
pHvalue
Conclusion
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Experiment2.Determinationofbloodserumbuffercapacity.Procedure.5mlofbloodserumwithpH=7.4areaddedtotwotest‐tubes.Inonetest‐tubeareadded5dropsofphenolphthaleinandsolutionistitratedwith0.1mol/lNaOHtilltheappearanceof thesamecolorascolorofreferencesolutionthathaspH=9.4. Inanothertest‐tube methyl orange is added and solution is titrated with 0.1 mol/l HCl till theappearanceofthesamecolorascolorofreferencesolutionthathaspH=3.4.
Thenthebuffercapacityiscalculatedbyacidandbybasewithequations(1)and(2).
(1)
(2)where:Вb–buffercapacitybybase;
Вa–buffercapacitybyacid;n(HCl),n(NaOH)–quantityofaddedacidorbaseto1lbuffersolution.рН1andрНs–initialandfinalvaluesofpH(tilltitrationandaftertitration).Vs–thevolumeofbloodserum;V(NaOH),V(HCl)–thevolumesofbaseandacidusedfortitration,c(NaOH),c(HCl)–theconcentrationofbaseandacidconsumedduringtitration.
In the conclusion compare the buffer capacity of blood serum by acid and by base andexplainwhythebuffercapacitybyacidisgreaterthanthecapacitybybase.Results:
Conclusion:
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Self‐trainingquestions1. Theoryofsolutions.2. Water–physicalandchemicalproperties,roleinthelivingorganisms.3. Electrolyticdissociationtheory–basicconcepts.4. ThemainconceptsofBronsted‐Lowryprotolytictheoryofacidsandbases.5. Waterdissociation.Theionicproductofwater.6. ThenotionofpH.Solution’spHandpOHmethodsofdetermination.7. The buffer solutions. Principles of buffering. Henderson‐Hasselbalch equation. Buffer
capacity.8. BodyliquidspHlevel.Biologicbuffersystems.
Casestudy
1. Show the composition and themechanism of action of the phosphate buffer systemafteradditionofsmallamountsofstrongacidsorbases.ThepHequationofphosphatebuffer.
2. The content of hydrochloric acid ranges from 0.07 to 0.15% in normal gastric juiceCalculatetherangeofpHchangeignoringtheinteractionforcesbetweentheН+andCl¯ions. C
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3. TochangethepHof100mlbloodfrom7.36to7.0isnecessarytoadd36ml0.05mol/lHClsol.Calculatebuffercapacityoftheblood.
Self‐assessmenttests
1.What abnormal physical properties ofwater are essential for a normal functioning ofhumanorganism?
a) lowboilingpoint;b) highboilingpoint;c) bigheatcapacity;
d) lowheatcapacity;e) highpermittivity
2.Atomsofwhichelementsincompoundscanformhydrogenbondswithhydrogen?
a) carbon;b) sulfur;
c) phosphorus;d) oxygen;
e) nitrogen
3.Whatmixturesfromthelistedbelowareconsideredbuffersystems?
a) sulfuricacid+sodiumsulphate/H2SO4+Na2SO4;b) carbonicacid+sodiumbicarbonate/H2CO3+NaHCO3;c) aceticacid+sodiumacetate/CH3COOH+CH3COONa;d) aceticacid+ammoniumacetate/CH3COOH+CH3COONH4;e) sodiumdihydrogenphosphate+disodiumhydrogenphosphate/NaH2PO4+Na2HPO4
4.Whatfactorsaffectbuffercapacity?
a) thecomponentsofbuffersystem;b) thestrengthofacidsandbases;c) thevaluesofрКаandрКbofweakacidsandbases;d) thecomponentsconcentrationandtheirratio;e) thepHofbuffersystem.
5.Themainbloodbuffersystemsare:
a) hemoglobin–oxyhemoglobin;b) ammoniabuffersystem;c) hydrogencarbonatebuffersystem;d) phosphatebuffersystem;e) aminoacidbuffersystem.
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6.Select thecorrect statementsconsidering the following two solutions:A. bufferwithH2PO4–=0,1M,HPO42–=0,2M;B.bufferwithH2PO4–=0,15M,HPO42–=0,3M.
a) solutionAhasahigherpH;b) solutionBhasahigherpH;c) bothsolutionhavethesamepH;d) solutionAhasahighercapacity;e) solutionBhasahighercapacity.
7.SupposeweprepareabufferwithanacidHA,thathasthepKaof5.What is thepHwhen[A–]/[AH]=10?a) 1; b) 2; c) 3; d) 4; e) 5.
LESSON№3 Data_________________
Aminoacids–structure,classificationandbiomedicalimportance.
Primarystructureoftheproteins
Experiment №1. Identification of amino acids that contained weak‐bonded sulfur (Folreaction)Method'sprinciple:Weakly bonded sulfur fromproteins and peptides is eliminated byNaOHintheformofNa2S,whichinteractswithNa2PbO2toforminsolublePbS(darkbrownorblackprecipitate).
Note:FolreactionisnegativeforMetwhichcontainedstabile‐bondedsulfur.Procedure:Mixthereagentsaccordingtothetable.
Result:_________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________
№ Reagents Testtube1 Ovalbumine1% 5drops2 Folreagent 5drops
Boilthesolutionfor1‐2min
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Experiment№2.XantoproteicreactionMethod'sprinciple:AromaticaminoacidsarenitratedwhileboilingwithHNO3and thesolutioncolorternsyellow.Additionofalkalichangethecolorinorange.
Procedure:
№ Reagents Testtube1 Ovalbumine1% 5drops2 HNO3concentrated 5dropsBoilafewminutesCoolthesolution3 NaOH20% 10drops
Result:_________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________Experiment№3.NinhydrinreactionMethod'sprinciple:Ninhydrinreactswith‐aminogroupsofaminoacidsandproteinstoformablue‐violetcompound.
Procedure:Mixthereagentsaccordingtothetable.
№ Reagents Testtube1 Ovalbumine1% 5drops2 Ninhydrine0,5% 5dropsBoilthesolutionfor1‐2min
Result:_________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________
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Experiment№4.BiuretreactionMethod's principle: Peptidic bonds react with CuSO4 in alkaline conditions to formcomplexcompoundscoloredinred‐violet
Procedure:
№ Reagents Testtube1 Ovalbumine1% 5drops2 NaOH10% 5drops3 CuSO41% 2dropsShakethoroughly
Result:_________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________
Self‐trainingquestions:1. Aminoacids–roleinthelivingorganism.Proteinogenicandnon‐proteinogenicamino
acids.2. Classification of amino acids according to their chemical structure, physico‐chemical
andacid‐baseproperties.3. Aminoacidsproperties–stereoisomery,solubility,acid‐baseproperties.4. Chemical properties of amino acids – reactions of carboxylation, decarboxylation,
hydroxylation,deaminoationandtransamination.5. Polypeptidetheoryoftheproteinstructure.Peptidebondproperties.Nameandreading
theaminoacidsinpeptidesandproteins.N‐andC‐terminalaminoacids.6. Methodsfordeterminationofaminoacidcompositionandsequenceinthepolypeptide
chain.
Casestudy:1. Divide the following amino acids in groups according to the biological classification:
Thr,Cys,Phe,Gln,His,Met,Gly,Arg.Writeapeptide that consistsof essential aminoacids.Givethedefinitionof"essentialaminoacid",indicatetheaminoacidsthatbelongto this group and the sources of these amino acids? In which proteins are all theessentialaminoacidspresent?
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2. Dividetheproteinogeneaminoacidsaccodingtotheirphysico‐chemicalproperties.Fillinthetable.
Hydrophobicaminoacids
Hydrophilicneutralaminoacids
Hydrophilicbasicaminoacids
Hydrophilicacidaminoacids
3.Writethestructureandshowtheroleofthefollowingnon‐proteinogenicaminoacids.
Amino‐acid Structure RoleBeta‐alanine
Homocysteine
Gamma‐aminobutiricacid
DOPA–dioxyphenylalanine
Ornithine
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4.Towhichelectodethefollowingaminoacidswillmovetoainsolutionwithacid,neutralandbasicpH?
Aminoacid pH<7.0 pH=7.0 pH>7.0Alanine Serine Lysine Asparticacid Glutamine
5.WritethereactionofglutamatesidechaincarboxylationinCa2+‐bindingproteins.Whatisthebiologicimportanceofthereaction?
6. Write the reactions of histidine and glutamate decarboxylation. What is the biologicimportanceofthesereactions?
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5. Write the reactions of alanine and aspartic acid transamination with alpha‐ketoglutarate.Whatisthebiologicimportanceofthereaction?
6.Writethefollowingtripeptides:Lys‐Val‐Pro;Glu‐Pro‐Arg;Pro‐Asp‐His.Highlightclassicandatypicpeptidebondsandshowtheirdifferences.
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Testsforselfassessment:1.Whatgroupsofaminoacidsarepresentinproteins?
a) hydroxyaminoacidsb) homocyclicaminoacidsc) beta‐aminoacids
d) diaminodicarboxylicaminoacidse) D‐aminoacids
2.Whatcyclicstructuresarepresentinaminoacidsencounteredintheproteinsandtowhichamino‐acidsidechaintheybelong?
a) purine phenylalanineb) indole triptophanec) imidazole histidined) pyrimidine prolinee) skatole tyrosine
3.Selectthecorrectparis–aminoacid–functionalgroupspecificforthesidechain:
a) arginine guanidinob) alanine thioc) tyrosine phenyld) cysteine hydroxye) triptophane indole
4.Selectnon‐polarhydrophobicaminoacids:
a) Ser b)Val c)Ile d)Trp e)Glu.
5.Selectthebasicaminoacids:a) Ala b)Ser c)Tyr d)Gln e)Lys
6.Selectthecorrectstatementsregardingserine:
a) isahydroxyaminoacidb) itsisoelectricpointisinbasicpHc) isa"non‐essential"aminoacidd) isan"essential"aminoacide) inasolutionwithpH=4migratestotheanode.
7.Selectthecorrectstatementsregardingarginine:
a) atpH=3hasanegativechargeb) itsisoelectricpH(pI)isinalkalinemediac) inhydroxylatedformispresentincollagenstructured) isanaminoacide) hasaguanidinegroupinitsstructure.
8.Whichstatementsarecorrectaboutmethionine?
a) isaderivativeofbutanoicacidb) containsweak‐bondedsulfurc) atpH=7migratestothecathoded) insolutionswithapHlessthanpIitmigratestotheanode;e) isanon‐essentialaminoacid.
9.Whichbondisspecificfortheprimarystructureofproteins?
a) hydrogenb) peptide
c) estherd) ionic
e) disulphide
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LESSON№4 Data_________________
Proteinstructureandfunction.Classificationofproteins.Generalcharacteristicofsimpleandconjugatedproteins
Experiment1.ChromatographycalidentificationoftheaminoacidsMethodsprinciple: Amino acids have different distributive coefficient in water and inorganic solvent (butanol). Amino acid’s velocity of migration is directly proportional totheirsolubilityinbutanol.Procedure:1.Markthetake‐offlineonthechromatographycalpaperwithapencil.2.Pipetteadropofaminoacidsmixtureinthemiddleofthestartingline(thediameterofthespotmustbelessthen5mm),drythespot.3. Introduce the chromatographycal strip in a vessel with the solvents mixture (water‐butanol).Thestripmustbeinverticalpositionandnottouchthevessel.4.Takethestripoutofthevesselwiththesolventsafter90min,markthedistancepassedbythesolvent(useonlypencil)anddrythechromatogram(10minat70‐100ºC).5.Passthestripthrough0,1‐0,2%ninhydrinsolutionanddryitat100ºC.Onthestripwilldevelopseveralcolouredspots.Eachspotcorrespondtooneaminoacid.6.Measurethefollowingdistances:a –fromthetake‐offlinetothemiddleofeachspot;b –fromthetake‐offlinetothesolvent'sfront.
Calculation:thedistributivecoefficientsforeachaminoacidiscalculatedaccordingtothenextformula:Rf=a/b.TheaminoacidsareidentifiedaccordingtothestandardRftable.
StandardRfvalues Drawtheobtainedchromatogramandmarkthetake‐off
line,distances„a”and„b”.
Measurethedistances„a”and„b”.
CalculateRf,Aminoacid
RfAminoacid
Rf
Histidine 0.11 Cysteine 0.40 Glutamine 0.13 Proline 0.43Lysine 0.14 Tyrosine 0.45Arginine 0.20 Asparagine 0.50Asparticacid
0.24 Methionine 0.55
Glycine 0.26 Valine 0.61Serine 0.27 Triptophane 0.66Glutamicacid
0.30 Phenilalanine 0.68
Threonine 0.35 Isoleucine 0.72Alanine 0.38 Leucine 0.73
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Conclusion:Whichaminoacidsarepresentinthesolution?__________________________________________________________________________________________________________________________________________________________________________________________________________________Clinical significance: Thismethod allows to determinewhich amino acids and inwhatamountarepresent indifferentbiologicalsamples.Assaysofdifferentbiologicalsamplesfor amino acid's content and composition are indispensable in clinical diagnosis ofnumeroushereditaryerrorsofmetabolism,liver,kidneysdiseasesetc.
Self‐trainingquestions:
1. Protein levels of structural organization: primary, secondary, tertiary and quaternarystructures,generaldescription.Chemicalbondsthatstabilizeeachstructurallevel.Basicnotionsaboutproteinstructuraldomains.
2. Proteinsclassification.3. Simpleproteins:albuminsandhistones–generalcharacteristic,structuralpeculiarities.Biologicrole.
4. Conjugated (complex) proteins: nucleo‐, phospho‐, lipo‐, glyco‐, chromo‐ andmetalloproteins;theirgeneralcharacteristic.
5. Globularproteins:hemoglobin–structureandbiologicrole.6. Fibrillar proteins: collagen and elastin – peculiarities of amino acids composition andstructure.Biologicrole.
7. Ca2+‐binding proteins: clotting factors, Ca2+‐ATPase, calmodulin and collagen.Peculiaritiesoftheaminoacidcompositionthatensurecalciumfixation.Biomedicalrole.
Casestudy:
1.WhatchangeofthehemoglobinstructureischaracteristicforHbSthatcausessicklecellanemia? What repercussions has this change of the primary structure on the upperstructurallevelsoftheprotein,itsfunctionandstateoftheerythrocytes?
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2. Collagen, calmodulin, plasma coagulation factors II,VII, IX andX, etc. areCa2+‐bindingproteins. What is the common structural property of these proteins? What vitaminensuresthisproperty?Whatarethesourcesofthevitamin?Whataretherolesoftheseproteinsinthebody?
Writethereactioninwhichisinvolvedthisvitamin.
3.Fillinthetable:Thisisthedeffinitionof
Thesequenceofaminoacidsinthepolypep‐tidechain,thatisgeneticallydetermined
Thisisthedeffinitionof Isformedduetotheinteractionofα‐carboxylgroupofoneaminoacidwithα‐aminogroupofthenextaminoacid
What structure has thisproperty?
Coplanarity
What chemical bond hasthisproperty?
resonanceformes(ketoorenol)
Write the structure whichwillilustratethestatement
transpositionofthesubstituentsinrespecttothelinkC‐N
Whatchemicalbondhas thecapacitytoformhydrogenbonds
Example:each peptide group canformtwohydrogenbonds
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4.What are the similarities and differences of hemoglobin andmyoglobin structure andfunction?What type of hypoxia develops in hemoglobin deficiency?What is the normallevelofhemoglobinintheblood?
Testsforself‐assessment:
1.Selectthecorrectstatementsaboutthesecondarystructureoftheproteins:a) isthearrangementintoanorderedstructureofthepolypeptidicchainb) itisdeterminedbyhydrophobicandionicinteractionsc) canbealpha‐helixandbeta‐structured) itisstabilizedbyhydrogenbondinge) itisstabilizedbypeptidebonds
2.Selectthecorrectstatementsaboutthesecondarystructureoftheproteins:
a) occursduetoionicbondingoftheadjacentpolypeptidechainsb) hasminimalandmaximalperiodicityc) canbeboth–alpha‐helixandbeta‐structured) appears due to hydrogen bond formation within a single chain and between
adjacentchainse) itisstabilisedalsobydisulfidebondsthatareformedbetweenMetradicals.
3.Selectthecorrectstatementsaboutthealfa‐helix:
a) predominatesinfibrillarproteinsmoleculesb) possesshelicalsymmetryc) radicalsofaminoacidsareinvolvedintheformationofthebalpha‐helixd) thehydrogenbondsare formedbetween thegroups–C=Oand ‐NHthatbelong tothesamepolypeptidechain
e) thehydrogenbondsare formedbetween thegroups–C=Oand ‐NHthatbelong tothedifferentpolypeptidechain C
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4.Selectthecorrectstatementsaboutthetertiarystructure:a) functionsarebasedonconformationalchangesb) thedomainsarepartofthesestructurec) thedomainsdeterminespecialproteinfunctionsd) itispossibletheinteractionbetweenradicalsAA‐Cys‐Cyse) itispossibletheinteractionbetweenradicalsAA‐Ser‐Ser
5.Selectthepairofaminoacidswhichsidechainscanformhydrogenbonds:
a) Lys Leub) Phe Val
c) Asp Alad) Ser Cys
e) Asn Thr
6.Selectthepairofaminoacidswhichsidechainscanformionicbonds:
a) Lys Glub) Trp Ile
c) Asp Argd) Gln Val
e) His Met
7.Selectthecorrectstatementsaboutthecuaternarystructureofproteins:
a) istheorganizationofsubunitsinasinglefunctionalproteinmoleculeb) is formed due to the non‐covalent bonds between the contact surfaces of thedomains
c) isrigidandstabled) isformedduetocovalentbondinge) isnotdestroyedbydenaturation
8.Selectthecorrectstatementsaboutthecuaternarystructureofproteins:
a) assemblyofthemoleculegoesthroughthestageofintermediatecompoundsb) isfavoredbyhydrophobicinteractionsbetweentheradicalsofaminoacidsc) functioningofproteinsiscorrelatedwiththemovementdomeniiord) isspecificforhemoglobine) isspecificformyoglobin
9.Selecttheoligomers:a) hemoglobin(Hb)b) myoglobinc) LDH(lactatedehydrogenase)d) immunoglobulinse) creatine
10.Selectthecorrectstatementaboutcollagen:
a) thepolypeptidechainshowsclassicalalphahelixconformationb) containsalotofcysteinc) ispresentonlyintracellulard) thestructuralunitofcollagenistropocollagene) tropocollagenunitsareconnectedbyweak,non‐covalentbondsincollagenfibers
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LESSON№5 Data_________________
Physico‐chemicalpropertiesofproteins.Thepurificationandanalysisofproteins
Experiment№1:DialysisMethod's principle: Dialysis (fromGreekδιάλυσις,diàlysis, "dissolution"; from διά,dià,"through",andλύσις,lỳsis,"looseningorsplitting")isamethodofseparationonthebasisofmolecularsize.Smallmoleculescanberemovedfromsolutionsbecausetheypassthroughsemipermeablemembrane.Proteinsarelargerthantheporesofthemembraneanddon'tcrossit.Procedure:1. Mixinaflask20mlsolofovalbumineand20dropsofsaturatedsolutionof(NH4)2SO4.2. Putthesolutioninacellophanebagandimmerseditinaglassfullofdistillatedwater.3. After60minpulloutthebagandtransferthesolutionintoatest‐tube.Identifyproteinand(NH4)2SO4inbothsolutions.
4. Thepresenceofproteinsisdeterminedbybiureticreaction(seeThemenr.1).5. The presence of (NH4)2SO4 is determined with BaCl2. To 5 drops of experimentalsolution add 3‐4 drops of 5% sol. BaCl2. Formation of insoluble BaSO4 certified thepresenceofSO42‐.
BaCl2+(NH4)2SO4BaSO4+2NH4Cl
6. Fillinthetable:
Solution
Compundspresentbefor
dialysis
DIALYSIS
Biureticreaction
ReactionwithBaCl2
Whatcompound–theproteinorSO42‐,ispresentinthesolutionn?
fromthebagProtein
(ovalbumine)(NH4)2SO4
fromtheglass
H2O
Clinicalvalue:Inmedicalpracticedialysisisamethodusedtoremoveexcesswater,othernormalcompundsandwastesfromthebloodofthepatientswhosekidneyshavelosttheirfunctions.Dailysiscanbetemporaryinpersonswithacutekideyfailureorwhoarewaitingfortransplantandchronicifthetransplantisnotindicatedorpossible.Conclusion:_____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
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Self‐trainingquestions:1. Molecularmassoftheproteins.Generalnotionsaboutthemostimportantmethodsfordetermining protein mass – ultracentrifugation, chromatography and massspectroscopy.
2. Amphoteric properties of the protein. The electric charge of the protein. Factors thatdeterminetheelectricchargeoftheprotein.Isoelectricpointandstate.Electrophoresis–principleandbiomedicaluse.Electrophoresisofbloodplasmaproteins.
3. The solubility of the proteins according to the conformation of themolecule and theamino acid composition, solution pH and temperture. Colloidal solutions of proteins.Factorsthatstabilizetheproteincolloidalsolution.Statesofthecolloidalsolutions:sol,gel,xerogel.
4. Denaturation of proteins, agents causing denaturation. Structural changes indenaturatedproteins.Biomedicalrole.
5. Methods of protein separation, purification and analysis: salting, dialysis,electrophoresis and chromatography (ion exchange chromatography, size exclusionchromatography/gelfiltrationchromatographyandaffinitychromatography).Method'sprincipleandbiomedicalimportance.
Casestudy:
1. Writetripeptideswiththeisoelecticpoint(pI)inacidic,neutralandbasicpH.
2. Divide into groups according to their solubility the following proteins: albumin,hemoglobin, keratin, transferrin, IgM, fibrin, prothrombin, collagen. What factorsinfluencethesolubilityoftheseproteins?
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3. Albuminsandhistonesaredissolvedinasolution.Selectbuffersolutionthatshouldbeusedforprecipitationofeachprotein:Sol.1,pH=4.0;Sol.2pH=7.0;Sol.3pH=11.0.Whatisthemechanismofseparationofindividualproteinsfromthemixturebythismethod?
4. Asolutioncontainingamixtureofalbuminsandglobulins is treatedwithammoniumsulfate([NH4]2SO4)tosemisaturation,andthentosaturation.Whateffectwillhavethistreatmentonthesolubilityofalbuminsandglobulins?Whatisthemechanismofactionof[NH4]2SO4ontheproteinsfromthesolution?
5. WhichelectrodealbuminsandhistoneswillmovetoatpH=7,0,ifthestartingpointisin
themiddlebetweenanodeandcathode?Explain.
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6. Whatmethodofthoselistedbelowcanbeusedtopurifyfluids(serum,plasma,lymph)of harmful micro molecular substances: denaturation, hydrolysis, electrophoresis,dialysis,affinitychromatography?Describetheprincipleofthemethodanditsclinicalusefulness.
7. Itisnecessarytoseparateandpurifycertainenzymesfromanimalorplantsourcesfortheproductionofenzymedrugs.Whichofthelistedbelowmethodsisthemostquickand efficient one for the separation and purification of enzymes: denaturation,hydrolysis,electrophoresis,dialysis,affinitychromatography?Describetheprincipleofthemethod.
8. Whatcharacter–hydrophilicorhydrophobic,hasthefragment‐Gly‐Ser‐Asn‐Trp‐Tyr‐
from the primary structure of a protein?Where is located these sequence in the 3Dstructureof theprotein–on thesurficeof themoleculeor inside?Explain.Write thestructureofthesequence.
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Testsforselfassessment:1. SelectthepHrangethatcorrespondtotheisoelectricpointofthepeptide–Arg‐
His‐Lys‐Ala:a) 1,5–3,0 b)3,0–4,5 c)4,5–6,0 d)6,0–7,5e)7,5–9,0
2. Selectthecorrectstatementsabouttheproteinthatcontains10%Arg,26%Lys,13%Val,35%Pro,8%Ala,8%Gly,atphysiologicpH:a) movestotheanodeb) movestothecathodec) hasapositivenetcharge
d) hasanegativenetchargee) doesnothavecharge
3. Selectthecorrectstatementaboutproteinsolubility:a) fibrillarproteinsarewellsolubleinpurewaterb) dependsontheelectricchargeandaqueousmembranec) dependsonthetypeofthesolventanditstemperatured) fibrillarproteinsarebettersolublethenglobularonee) ismaximumattheisoelectricpoint
4.Selectthefactorsthatensurethestabilityoftheproteininthesolution:a) theaqueousmembrane(MA),whichisformedduetothehydrationofthehydrophilicfunctionalgroups
b) theelectriccharge,thatdependsonthepHofthesolutionc) electriccharge,thatdependsonthehydrophobicradicalsofaminoacidsd) theaqueousmembrane(MA),whichis formedduetothehydrationofhydrophobicfunctionalgroups
e) theelectricalchargeofthe"N"‐and"C"‐terminalaminoacids
5.Whatcandeterminetheprecipitationofproteins?a) aqueousmembranedamageb) neutralizationoftheelectricchargec) bringingthebasicproteintotheisoelectricstatebytheadditionofacidd) bringingtheacidproteintotheisoelectricstatebytheadditionofbasee) aqueousmembranedamagebyremovingfixedwater
6.Selectthecorrectstatementsaboutsalting:a) isthehydrationoftheproteinmoleculeb) isthedehydrationoftheproteinmoleculec) isanirreversibleprocessd) isfenomenonofmicromoleculespassingthroughthesemipermeablemembranee) destroysthetertiarystructureoftheprotein
7.Whatstatementsaboutthedenaturedproteinmoleculearecorrect?a) primarystructureisdestroyedb) thebiologicalactivityisincreasedc) tertiaryandquaternarystructuresaredestroyedd) thepeptidebondsaredestoyede) doesnotchangethenativestateofthemoleculeC
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8.Whatpropertiesarespecificforproteincolloidalsolution?a) increasedcapacityofdiffusionb) increasedviscosityc) lowdiffusioncapacity
d) opticalpropertiese) reducedviscosity.
LESSON№ 6 Data_________________
TestonChapterI–Chemistryofproteins
1. Bioelements – organogenic and minerals. Content and overview of the main
bioelementsthatmakeupthehumanbody.Biomolecules.2. Functional groups. Types of functional groups specific for biomolecules. Their
generalfeature.3. Typesofchemicalbondsspecificforbiomolecules.Theirgeneralfeature.4. Water–physicalandchemicalproperties,roleinthelivingorganisms.5. Electrolyticdissociationtheory–basicconcepts.6. ThemainconceptsofBronsted‐Lowryprotolytictheoryofacidsandbases.7. Waterdissociation.Theionicproductofwater.8. ThenotionofpH.Solution’spHandpOHmethodsofdetermination.9. Thebuffersolutions.Principlesofbuffering.Henderson‐Hasselbalchequation.Buffer
capacity.10. BodyliquidspHlevel.Biologicbuffersystems(bicarbonate,phosphate).11. Aminoacids–roleinthelivingorganisms.Aminoacidsproperties–stereoisomery,
solubility,acid‐baseproperties.12. Classificationofaminoacidsaccordingtotheirchemicalstructure,physico‐chemical
andacid‐baseproperties.13. Chemical properties of amino acids – reactions of carboxylation, decarboxylation,
hydroxylationandtransamination.14. Polypeptide theory of the protein structure. Peptide bond properties. Name and
readingtheaminoacidsinpeptidesandproteins.N‐andC‐terminalaminoacids.15. Methods for determination of amino acid composition and sequence in the
polypeptidechain.16. Levels of structural organizationof the proteinmolecule. Theprimary structure of
the protein. Inheritedmodifications of the primary structure ( sickle cell anemia).Proteinsecondarystructure:types,bondsthatstabilizesecondarystructure.
17. Levelsof structural organizationof theproteinmolecule .The tertiary structureoftheprotein.Typesofintramolecularbondsintheprotein.Quaternarystructureoftheprotein. Cooperative changes of protomers conformation (on the example ofhemoglobinandmyoglobin).Term"domain".
18. Globular and fibrillar proteins (hemoglobin, collagen) ‐ peculiarities ofconformationalandphysico‐chemicalproperties.
19. Calcium‐bindingproteins‐collagen,calmodulin,bloodclottingfactors.Peculiaritiesof aminoacid composition resulting calcium fixation .The roleof theseproteins inthebody.
20. The biological role of proteins. Albumin, globulins, histones – their features andbiologicalrole.Methodsfordeterminationandseparationofplasmaproteins.
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21. Classesofconjugatedproteins.General featuresofchromoproteins,metaloproteins,nucleoproteins, phosphoproteins, glycoproteins and lipoproteins, their biologicalrole,examples.
22. Physico‐chemicalpropertiesofproteins.The solubilityof theproteins.Factors thatinfluence solubility. Colloidal solutions of proteins, their properties, stabilizingfactors.Saltingout.Dialysisofproteins.
23. Electro‐chemical properties of proteins. Factors determining the charge of theproteins.Isoelectricstateandpoint.Proteinelectrophoresis.
24. Proteindenaturationandrenaturation.Denaturationfactors.
LESSON№7 Data_________________
Nucleicacids–classification,structureandrole.Nitrogenousbases,nucleosidesandnucleotides–structureandnomenclature
Experiment1:Molisch'sreaction(namedafterAustrianbotanistHansMolisch)Method'sprinciple:isbasedonthedehydrationoftheribosebysulfuricacidtoproduceanaldehyde(furfural),whichcondenseswithtwomoleculesofthymol,resultinginared‐orpurple‐coloredcompound.Procedure:
№ Reagents Testtube1. Yeasthydrolyzate 10drops2. Thymolsol.1% 3drops
Thoroughlyshakethesolution.PourtheH2SO4solutionontothetesttubewall.3. H2SO4concentr. 20‐30drops
Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________Experiment2:Molybdenumreaction(phosphoricacididentification)Method'sprinciple:Whenphosphoricacidistreatedwithmolybdenumreagentayellowsedimentisproduced.Procedure:
№ Reagents Testtube1. Yeasthydrolyzate 10drops2. Molybdenumreagent 20drops
Boilthesolution.Coolitinflowingwater
Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________ C
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Self‐trainingquestions:1. Typesofnucleicacids,functionsandcelllocation.2. Chemicalcompositionofnucleicacids:nitrogenousbases,pentosesandphosphate.3. Nucleosidesandnucleotides–structureandfunctions.4. PrimarystructureofDNA.Polynucleotidechain.Phosphodiesterbonds.5. Secondary and tertiary structure of DNA. DNA double helix – Watson‐Crick model
(typesB,AandZ).LevelsofcompactionofDNAmoleculeinprokaryotes(nucleoid)andeukaryotes(nucleosomesandsolenoid).
6. RNAprimary,secondaryandtertiarystructures.PeculiaritiesoftRNA,mRNAandrRNAstructure.
Casestudy:
1.Writetheformulasofthefollowingnucleotides5´‐thymidylacid,5´‐uridylacid,5´‐adenylacidand5´‐deoxyadenylacid.WhichofthesenucleotidesbelongtoDNAandRNA?Showtheglycosidicandestherbonds.
2.WriteinyournotebookthechemicalstructureofthepolynucleotidesequencedT‐dC‐dG‐dA.Which nucleic acid this sequence belongs to?What will be the electric charge of
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given nucleic acid at physiological pH? What is the role of this electrical charge fornucleosomeformation?
3.WriteinyournotebookthechemicalstructureofthepolynucleotidesequenceG‐A‐U‐C.Whichnucleicacidthissequencebelongsto?Showthebondsspecificforthisstructure.IsitpossiblehydrogenbondsformationinRNA?Drawandexplaininwhichcasesthisispossible.
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4. Show the complementary interaction of cytosine with the corresponding nitrogenousbase.
5.ShowthestructureoftheDNAfragmentthatistranscribedifknownthatRNAcontainstheanticodonUGC.
6.WhichisthesequenceoftheanticodoneofthetRNAthatcarrytheaminoacidencoded
by the codoneUCG frommRNA.Whichpyrimidine base is complementar to guanine?Showhowhydrogenbondsbetweenthesenitrogenousbasesareformed.
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7. Represent the structural formula of a DNA fragment that contains two pairs ofcomplementarynitrogenousbases.
8.WritethestructureofATP,ADPandAMP.WhatareATPfunctions?
Testsforself‐assessment:
1.SelectthestructuralelementsofDNA:a) dehydrouracylb) deoxyribose
c) phosphated) thymine
e) ribosylthymine
2.SelecttypesofchemicalbondsthatarepresentinDNA:a)peptidicb)3',5'‐
phosphodiesterc)N‐glycosidic
d)ionicinteractionse)hydrogenbonds
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3.SelectthecorrectstatementsregardingthestructureofDNA:a)isdoublestrandedb)strandsareparallelc)nitrogenousbasesarelocatedinsidethedoublehelixd)strandsarelinkedbetweenthembyphosphodiesterbondse)strandscannotbeseparatedathightemperature
4.SelectcorrectstatementsaboutDNA:a)classic„B”formofDNAcontains10basepairsperturnb)„V”formofDNAcontains11basepairsperturnc)„Z”formcontains12basepairsperturnandisleft‐handedspirald)forallDNAisspecifictheratioG+C/A+T=1e)mainlyislocatedinthecytosol
5.Selectcorrectstatementsaboutnucleosome:a)histoneproteinsareorganizedinoctamers‐doublesetofH4,H3,H2A,H2B;b)octamereiswrappedbydoubleDNAringlengthof146nucleotides;c)arelocatedinmitochondriad)isaformofRNAsupraorganizatione)aremoleculesofextrachromosomalDNA
6.SelectthecorrectstatementsregardingRNA:a)themoleculeismainlydouble‐strandedb)nucleotidecompositioncorrespondtocomplemetatitylawc)theRNAquantityinthecellisconstantd)itisasingle‐strandedpolyribonucleotidee)thespecificnucleotidesareATP,GTP,TTPandCTP
7.SelectthecorrectstatementsregardingmRNA:a)areveryheterogenousmoleculesb)eachgenehasacorrecpondingmRNAmoleculec)aresynthesizedinthecytoplasmd)containsmethylatedguanineatthe5´‐endc)itisconstantlyattachedtotheribosomes
8.SelectthecorrectstatementsregardingtRNA:a)the5´‐endcontainstheCCAtripletb)containsmanyminornitrogenousbasesc)theaminoacidisattachedtothe3´‐endd)contains75‐90nucleotidese)3´‐endcontainstheanticodone
9.SelectthecorrectstatementsregardingtRNA:a)aremoleculeswithsimilarstructureandshapeb)thesecondarystructureofalltRNAhastheshapeofthecloverleafc)allmoleculesarefreeinthecelld)arestructuralelementsoftheribosomese)arecompletelydouble‐strandedmolecules
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LESSON№8 Data_________________
Carbohydrates:classificationandbiologicalrole.Monosacchirides–structure,isomerism,propertiesandbiomedicalimportance
Experiment№1:GlucoseidentificationbyTrommerreaction.Method'sprinciple:WhenglucoseistreatedwithCu(OH)2inalkalinesolution,abrick‐redprecipitateofCu2Oisformed.
CuSO4+2NaOHNa2SO4+Cu(OH)2blue
Glucose+2Cu(OH)2gluconicacid+H2O+2CuOHyellow2CuOHH2O+Cu2Obrick‐red
Procedure: № Reagents Test‐tube1 glucose 2drops2 10%NaOH 6drops3 2%CuSO4 1drop4 H2O 3‐4drops5 Thecolourofthesolution 6 Heatcarefullthemixture7 Thecolourofthesolution
Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________Experiment№2:FructoseidentificationbySeliwanoff’stestMethod'sprinciple:Seliwanoff’s testisa testwhichseparatesaldoseandketosesugars.Keto sugars are dehydrated by concentrated acids (HCl) to yield furfurals or theirsubsidiaries which react with resorcinol in Seliwanoff reagent to yield a cherry‐redcomplex.Whenaddedtoaldoses,aslowerformingpinkcolorisseen.
Procedure:
№ ReagentsTest‐tubes
I II1 Resorcinpouder 1‐2grains 1‐2grains2 HClconcentr. 2drops 2drops3 Fructose0.5% 2drops 2drops4 Glucose0.5% 2drops 2drops5 Boilfewminutes6 Thecolourofthesolution C
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Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________
Self‐trainingquestions:1. Thebiologicalroleofcarbohydrates.2. Classificationandstructureofthecarbohydrates.3. Structure and properties of the main monosaccharides (glyceraldehyde,dihydroxyacetone,ribose,deoxyribose,glucose,galactose,fructose).
4. Stereoisomerism of monosaccharides: enantiomers, D‐ and L‐ stereoisomers,diastereolsomersandepimers.
5. Linear and cyclic forms of the monosaccharides. Closed ring structure of 5 or morecarbon atoms (pyranose and furanose rings) monosaccharides. Haworthprojections.The role and properties of the hemiacetal hydroxyl, notions of α‐ and β‐anomers.
6. Important chemical reactions ofmonosaccharides (formation of phosphoric esters,N‐andO‐glycosides,oxidationandreduction).
7. Ascorbicacid(vitaminC)structure,synthesisandrole.8. Aminated carbohydrates: glucosamine, galactosamine and sialic acid – structure,formationandbiologicrole.
Casestudy:
1. Which are the similarities and differences between glyceraldehyde anddihydroxyacetone?
Glyceraldehyde DihydroxyacetoneSimilarities
Differences
2. Write the structure of the following compounds and show the difference in theirstructures:
D-glucose L-glucose Type of isomerism
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α‐D‐glucopyranose β‐D‐glucopyranose Type of isomerism
α‐D‐glucopyranose α‐D‐galactopyranose Type of isomerism
3.WritethestructureoftheD‐glucose,D‐galactose,D‐riboseandD‐fructoseanomers.
4.Writethereactionofglucose‐6‐phosphateformationintheorganism.
5.Write thereactionsofD‐glucoseandD‐galactoseoxidation tillgluconicandglucuronicacids.
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6.Ascorbicacid(vitaminC)issynthesizedfromD‐glucoseandistheγ‐lactoneofthe2‐oxo‐L‐gulonicacid.Writetheschemeofvit.CsynthesisfromD‐glucose.Forwhichorganismsisthissyntheticpathwayspecific?Whatisthebiologicroleofthevitamin?
Testsforself‐assessment:1.Functionsofcarbohydratesa)energeticfunctionb)tomaintainoncoticpressurec)areemulsifiers
d)areconstituentsofconnectivetissueandnucleicacidse)transport
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2.Choosecarbohydratesthatarepresentinthehumanbody:a)amyloseb)glucosec)glycogen
d)ribose,deoxyribosee)amylopectin
3.Selectthecorrectstatementsaboutglucose:a)isapolysaccharideb)isaketosec)isanaldohexose
d)has2anomers–alphaandbetae)doesnothaveasymmetriccarbons
4.Selectthecorrectstatementsaboutfructose:a)isanaldopentose
b)isanaldohexosec)isaketopentose
d)isaglucoseisomere)isthemainmonosacchridefromtheblood
5.Selectthemetabolicactiveformofglucose:a)glucosamineb)acetyl‐glucose
c)phosphoricestherd)methylglucose
e)glucosesulfate
6.Whichstatementischaracterizingthemonosaccharides?a)allmonosaccharidescanproduceintramolecularhemiacetalsb)arepolyhydroxycarbonylcompoundsc)areclassifiedinessentialandnon‐essentiald)allmonosaccharideshaveanomerse)canbehydrolysed
7.Choosethecorrectstatementsregardingthestereoisomerismofmonosaccharides:
a)enantiomersdonotpossessopticalpropertiesb)diastereoisomersdifferintheconfigurationofallchiralcarbonatomsc)epimersarediastereoisomerscharacterizedbytheconfigurationofoneasymmetricatomd)D‐mannoseistheepimerofD‐glucoseatthesecondcarbonatome)openformsofmonosaccharidesexistintheformofα‐andβ‐anomers
8. Indicate the process (2) during which these derivatives of carbohydrates areformed(1)‒drawarrows:
a)sorbitol oxidationofglucoseb)glucuronicandiduronicacids reductionofglucoseandfructosec)mannitol reductionofribosed)glucose‐6‐phosphate reductionofmannoseandfructosee)deoxyribose esterificationofglucose
9.Selectthestructuralelementsoftheneuraminicacid:
a)aceticacidb)pyruvicacid
c)galactosamined)glucuronicacid
e)mannosamine
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LESSON№9 Data_________________
Olygoandpolysaccharides–structure,propertiesandbiomedicalimportance
Experiment №1: Demonstration of the reducing properties of carbohydrates(Fehlingreaction)Method'sprinciple:WhenmonosaccharidesaretreatedwithCu(OH)2inalkalinemedium,abrick‐redprecipitateofCu2Oisformed:
CuSO4+2NaOHNa2SO4+Cu(OH)2blueGlucose+2Cu(OH)2gluconicacid+H2O+2CuOHyellow
2CuOHH2O+Cu2Obrick‐redProcedure:
№ ReagentsTest‐tubes
I II III IV V1 4‐5dropsof glucose Fructose succrose starch pathologi‐cal
urine2 Fehlingsolution 4‐5
drops4‐5drops
4‐5drops
4‐5drops
4‐5drops
3 Boilthemixtures4 Thecolourofthe
solution
Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________
Self‐trainingquestions:
1. Classification and structure of the olygosaccharides – reducing and non‐reducingdisaccharides(maltose,lactoseandsucrose).Biomedicalrole.
2. Classification,structure,propertiesandbiomedicalroleofthepolysaccharides:a) homopolysaccharides(glycogen,starch,cellulose)b) heteropolysaccharides(hyaluronicacid,chondroitin‐sulfateandheparin).
Casestudy:
1. Sucrosedoesnothavetwoanomerforms.Why?
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2. Whatistheonlydifferenceinthestructureofstarchandcellulose?Howthisdifferencereflectsthepropertiesofthecorrespondingpolysaccharides?
3. Ruminants use cellulose as food, but most mammals can not use it. Explain why.
Writethestructureofthestructuralunitofcellulose.
4.Trehalose–thenon‐reducingdisaccharidethatconsistof2moleculesofα‐D‐glucose,isa
structuralelementofthetoxinproducedbymanymicroorganisms.Writethestructureofthisdisaccharide.
5.Whichheteropolysaccharideconsistsofβ‐D‐glucuronicacidandN‐acetyl‐β‐D‐
glucosaminelinkedbyaβ(1→3)glycosidicbond?Writeitsstructureandexplainitsbiomedicalrole.
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Testsforself‐assessment:1. Selectthestructuralelementofmaltose:a)alpha‐glucoseb)beta‐glucose
c)alpha‐galactosed)beta‐fructose
e)alfa‐ribose
2. Selectthestructuralelementsofsucrose:a)alpha‐glucoseb)beta‐glucose
c)alpha‐galactosed)beta‐fructose
e)alfa‐ribose
3. Selectthestructuralelementsoflactose:a)alpha‐glucoseb)beta‐glucose
c)beta‐galactosed)alfa‐fructose
e)beta‐ribose
4. Selectthecarbohydratesthatcontainalpha‐glucose:a)glycogenb)starch
c)cellulosed)lactose
e)sucrose
5. Selectthecarbohydratesthatcontainbeta‐glucose:a)glycogenb)starch
c)cellulosed)lactose
e)sucrose
6. Selectthecorrectstatementsabouthomoglycans:a)structuralunitofcelluloseismaltoseb)celluloseisapolysaccharidethatpredominatesinplantsc)starchiscomposedofalpha‐glucosed)glycogeniscomposedofbeta‐glucosee)α‐1,6‐glycosidicbondspredominateinthestructureofcellulose.
7.Selectthecorrectstatementsregardingglycogen:a)isdepositedinscheletalmusclesb)isdepositedinadiposetissuec)isdepositedintheliverd)isusedtomaintainthenormallevelofbloodglucosee)itisnotproducedinthehumancells
8.Selectthechemicalbondsthatarespecificforstarch(amylose+amylopectin)andglycogen:
a)α(1→4)b)β(1→4)
c)α(1→6)d)β(1→6)
e)nonofabove
9.Selectthecorrectstatementsaboutheteroglycans:a)mainformsareamylaseandamylopectinb)hyaluronicacidconsistsofD‐glucuronicacidandN‐acetylglucosaminec)inhyaluronicacidthemonomersarelinkedbyβ‐(1→4)andβ‐(1→3)glycosidicbondsd)thereare6formsofchondoritinsulfatee)areimportantstructuralelementsoftheconnectivetissue
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10.Heparin‐selectthecorrectstatementregardingthecompound:a)isamineralcomponentofthebloodplasmab)isaproteinc)isadirectanticoagulantd)isaclottingfactore)isafibrinolyticfactor
LESSON№10 Data_________________
Water‐solublevitamins:B1,B2,B6,PP,biotin,pantothenic,folicandascorbicacidsandB12–structureandcoenzymefunction
Experiment№1:VitaminC(ascorbicacid)levelassayintheurineMethod's principle: Vitamin C has the property of reducing 2,6‐dichlorophenol‐indophenol(2,6‐DCPIP),whichleadstothechangeinthecolorofthesolution.
ascorbicacid+oxidized2,6‐DCPIP→dihydroascorbicacid+reduced2,6‐DCPIP(bluecolor) (pinkcolor)
Procedure:Nr. Reagents Test-tube 1 Urine 10 ml 2 Н2О dist. 10 ml 3 10% НСl sol. 20 drops 4 Initial color of the solution 5 Titrate with 0,001N 2,6-DCPIP solution 6 Final color of the solution
Calculation:TheamountofvitaminCintheurineisdeterminedbytheformula:
C(mg/24ore)=(0.088•A•C)/Bwhere:0,088‐conversionfactor; Aistheamountof2,6‐DCPIPusedtotitratethesample;
B‐theamountofurineusedintheexperiment(10ml);C‐dailydiuresis(onaverage‐1500mlinmenand1200mlinwomen).
Clinical significance:Humans cannot make vitamin C (ascorbic acid or ascorbate) andmustobtainitthroughthefoodorsupplements.VitaminCdisappearsfromtheurineearlyinbloodortissuedepletion.Plasmalevelsfallnextandtissuelevels(suchasinleukocytesandplatelets)arethelasttofall.VitaminClevelsinthebodyof1500mgsorlesswillresultin no urinary excretion of vitamin C. However, certain medications such as aspirin,aminopyrine,barbiturates,hydantoinsandparaldehydeaswellascoldorheatstressareknowntoincreasetheexcretionofvitaminCintheurine.Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________
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Self‐trainingquestions:1.Classificationandbiomedicalroleofvitamins.2.Water‐solublevitaminsB1,B2,B6,PP,biotin, pantothenic, folic andascorbic acids andB12: a)structure; b)coenzymesderivativesofthesevitamins; c)metabolicfunctionofthecoenzymesderivativesofthesevitamins; d)recommendeddailyallowances(RDAs)andfoodsources;
e)hypo‐andhypervitaminoses–causes,metabolicdisordersandclinicalsigns.
Casestudy:1.Fillinthetableasintheexample:
Vitamin Name Coenzyme BiologicroleHypovitaminosisMainclinicalsigns
B1 Thiamine Thiaminpyrophosphate(TPP)
Coenzymeoftheenzymesthatcatalyzetheoxidativedecarboxylationoftheα‐ketoacids
Beriberi,mentaldepression,mentalconfusion,peripheralneuropathy,ataxia,lossofeyecoordination
B2
B6
PP(B3)
H
B5
B9
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B12
C
Testsforself‐assessment:
1.Selectthefunctionsofthevitamins:a)energeticb)structural
c)transportd)coenzyme
e)genetic
2.Selectthechemicalcompoundsthatcanbecoenzymes:
a)nucleotidesb)proteins
c)hemd)peptides
e)triglycerides
3.Selectthecoenzymesthatcontainadenosinemonophosphates:
a)pyridoxalphosphateb)FMNc)FAD
d)NAD+e)thyaminepyrophosphate
4.Selectthecoenzymesofthedehydrogenases:
a)pyridoxalphosphateb)pyridoxaminephosphatec)thyaminepyrophosphate
d)FADe)NAD+
5.Selectthecoenzymesinvolvedinthetransferoftheaminogroup:
a)folicacidb)FADc)NAD+
d)pantothenicacide)pyridoxalphosphate
6.Selectthecoenzymesinvolvedinthetransferoftheonecarbongroups:
a)folicacidb)FADc)NAD+
d)pantothenicacide)pyridoxalphosphate
7.Selectthereactionsinwhichcanbeinvolvedbiotin:
a)carboxylationb)decarboxylationc)transcarboxylation
d)tranaminatione)dehydrogenation
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8.SelectthecorrectstatemetnsregardingVit.B12:a)containscobaltionb)participateinproteinsynthesisreactionsc)participateintheoxidationoffattyacidswithoddnumberofcarbonsd)participateintheoxidationofvaline,isoleucine,methionine,andthreoninee)ispredominantlypresentinfoodofplantorigin
LESSON№11 Data_________________
ConcludingtestonChapters„NucleicAcidsstructureandfunction”,
„Carbohydratesstructure,propertiesandfunctions”and„Watersolublevitamins”
1. Typesandfunctionsofnucleicacids.2. Structureofnitrogenousbases,nucleosides,nucleotidesandcyclicnucleotides.Chemical
bondsspecificforthenucleotides.Biologicalroleofnucleotides.3. StructureofDNA–doublehelix.Watson‐Crickmodel.TypesB,AandZofdoublehelix.4. Levels of DNA molecule compaction in prokaryotes (nucleoid) and eukaryotes
(nucleosomes,chromatinandchromosomes).5. Generalcharacteristicsandbiologicalroleofcarbohydrates.6. Classificationandfunctionsofcarbohydrates.7. Structureofcarbohydrates:
a)monosaccharides(glyceraldehyde,dihydroxyacetone,ribose,deoxyribose,glucose,galactose,mannose,fructose);b)disaccharides(maltose,lactose,sucrose);c)homopolysaccharides(glycogen,starch,cellulose);d)heteropolysaccharides(hyaluronicacid,chondroitinsulfateandheparin).
9. Stereoisomerism of monosaccharides: enantiomers, D‐ and L‐ stereoisomers,diastereolsomersandepimers.
10. Linear and cyclic formsof themonosaccharides. Closed ring structure of 5 ormorecarbon atoms (pyranose and furanose rings) monosaccharides. Haworthprojections.Theroleandpropertiesofthehemiacetalhydroxyl, notionsofα‐andβ‐anomers.
11. Importantchemicalreactionsofmonosaccharides(formationofphosphoricesters,N‐andO‐glycosides, oxidation and reduction). Ascorbic acid (vitamin C) structure androle.
12. Formationofamino‐carbohydrates(glucosamineandsialicacid),biologicrole.13. Classification of the olygosaccharides – reducing and non‐reducing disaccharides
(maltose,lactoseandsucrose).Biomedicalrole.14. Classification,propertiesandbiomedicalroleofthepolysaccharides:
a) homopolysaccharides(glycogen,starch,cellulose)b) heteropolysaccharides(hyaluronicacid,chondroitin‐sulfateandheparin).
14. Classificationandbiomedicalroleofvitamins.15. Water‐solublevitaminsB1,B2,B6,PP,biotin,pantothenic,folicandascorbicacidsand
B12:a)structure;
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b)coenzymesderivativesofthesevitamins;c)metabolicfunctionofthecoenzymesderivativesofthesevitamins;d)recommendeddailyallowances(RDAs)andfoodsources;e)hypo‐andhypervitaminoses–causes,metabolicdisordersandclinicalsigns.
LESSON№12 Data_________________
Lipids‒classification,structure,physico‐chemicalproperties,biologicalrole.Biologicalmembranes
Experiment№1:FormationofinsolublecalciumsaltsoffattyacidsMethod'sprinciple:Theexperimentisbasedonthefollowingreaction.
2CH3‐(CH2)n‐COOH+CaCl2→(CH3‐(CH2)n‐COO)2Ca+HCl
Procedure:
№ Reagents Test‐tubes
1. Soapsolution 5drops2. CaCl2sol. 1drop
Writethereactionofthecalciumsaltofstearicacidformation.
Rezult:_______________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________
Experiment№2:ThesolubilityofcalciumsoapinaceticacidMethod'sprinciple:Theexperimentisbasedonthefollowingreaction.
(CH3‐(CH2)n‐COO)2Ca+CH3COOH→2CH3‐(CH2)n‐COOH+(CH3COO)2Ca
Procedure:
№ Reagents Test‐tubes
1. Usetheprecipitateobtainedinthepreviousesperiment.
2. СН3СООН 2М 1dropRezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________
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Self‐trainingquestions:1. Biologicalfunctionsoflipids.2. Classificationoflipids(structural,functional,accordingphysico‐chemicalproperties).3. Saturated and unsaturated fatty acids. Structure, physico‐chemical properties,
representatives.Biomedicalrole.4. Triglycerides‒structure,physico‐chemicalpropertiesandbiomedicalrole.5. Glycerophospholipids: phosphatidylserines, phosphatidylethanolamines (cephalins),
phosphatidylcholines (lecithins), phosphatidylinositols – structure, physico‐chemicalpropertiesandbiomedicalrole.
6. Sphingomyelins‒structure,physico‐chemicalpropertiesandbiomedicalrole.7. Glycolipids: galacto‐ and glucocerebrosides, sulphatides, gangliosides ‒ structure,
physico‐chemicalpropertiesandbiomedicalrole.
Casestudy:1. Vegetable oils are liquid triglycerides and animal fats ‐ solid triglycerides. Write a
triacylglycerolstructurepresentinoilandatriacylglycerolpresentinanimalfat.Givetheirnames.
2. Whatfattyacidsareessentialforthehumanbody?Writetheirstructure.Whatarethe
mainfoodsourcesoftheessentialfattyacids?
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3. What are the products of the basic hydrolysis of phosphatidylcholine that containsstearicandoleicacids?Writethereactionofthehydrolysisprocess.
4. Writethereactionsoftheacidhydrolysisofthefollowingtriglycerides:dioleostearine,linoleodioleineanddipalmitostearine.
5. Writethestructuresofphosphatidylcholinethatcontainspalmiticandoleicacidsand
of phosphatidylehtanolamine that contains linoleic and stearic acids. Show the polarandnon‐polarpartsofthemolecules.
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6. Write the the structures of sphingolipids (ceramide and sphingomyeline) andcerebroside that contain the following fatty acids – palmitic, stearic, oleic andarachidonic.
Testsforself‐assessment:1. Selectthefattyacidsthatareessentialhumans:a)lignoсericb)oleicc)palmitoleic
d)linolenice)linoleic
2. Selectthemonoenicfattyacids(withonedoublebond):a)palmiticb)oleicc)palmitoleic
d)linolenice)linoleic
3. Selectthepolyenicfattyacids(withtwoormoredoublebonds):a)arahidonicb)oleicc)palmitoleic
d)linolenice)linoleic
4. Selectthecorrectstatementsregardingtriglycerides:a)areconstituentsofbiologicalmembranesb)areestersofglycerolandfattyacidsc)representaformofenergystoraged)aresolubleinwatere)arederivativesofphosphatidicacid
5. Selectthecompoundfromwhichthephospholipidsaresynthesized:a)glycerolphosphateb)phosphatidicacidc)phosphoricacid
d)triglyceridese)ceramides
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6. Selectthepolarlipidsfromthefollowing:a)phosphatidylcholineb)phosphatidylserinec)phosphatidylethanolamine
d)phosphatidyinositole)triglycerides
7. Selectthelipidsthatcanproducebilayers:a)triglyceridesb)phosphatidylserinec)phosphatidyl‐ethanolamine
d)phosphatidyinositole)ceramides
8. Selectthecorrectstatementsaboutphosphatidylcholineandphosphatidylethanolamine:a)arerepresentativesofwaxesb)arethemaincomponentsofcellmembranesc)representaformofenergystoraged)arederivativesofphosphatidicacide)havedifferentelectriccharge
9. Selectthecorrectstatementsaboutsphingosine:a)isasaturateddihydroxyaminoalcoolb)isacomponentofsphingomyelinec)isacomponentofglycolipidsd)isaconstituentofglycerophospholipidse)doesn’tenterinthecompositionoftheceramide
10. Selectthecorrectstatementsaboutcerebrosides:a) don’tcontainsphingosineb)containabeta‐galactoseorabeta‐glucoseboundtoceramidec)containoligosaccharidesd)sulfatidesareaclassofsulfatedcerebrosidese)thewhitematterofthebraincontainscerebrosidesinlargeamounts
11.Selectthecorrectstatementsaboutgangliosides:a)containseveralresiduesofglycerolb)containN‐acetylneuraminicacid(NANA)c)containonlyglucoseintheoligosaccharided)containsulfateresidueslinkedtogalactosee)aresituatedontheinnersurfaceofmembranes
LESSON№13 Data__________
Cholesterolanditsderivatives.Steroidhormones.Bileacids
Experiment№1:EmulsificationcapacityofthebyleacidsMethod'sprinciple:Emulsificationistheprocessofmakinganemulsion,allowingfatandwater tomix, by breaking downof large fat globules into smaller, uniformly distributed
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particles.Canbeaccomplishedinthesmallintestinethroughtheactionofbileacids,whichlowertensionatthewatter‐lipidssurfaceduetopolarproperties.Procedure:
Reactive Itest‐tube IItest‐tubeOil 1drop 1dropWater 5drops 5dropsBile ‐ 5drops
Shakethetest‐tubes.Howlonglasttheemulsion
Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________Experiment№2:Identificationofbileacids(Pettencofferreaction)Method'sprinciple:WhensucroseistreatedwithconcentratedH2SO4oxymethylfurfurolisformed.Itreactswithbileacidtogenerateared‐violetcomplexcompound.Procedure:Putintoatest‐tube:
Reactive Bile 2dropsSucrose20% 2drops
Shakethetest‐tube.ConcentratedH2SO4 5‐6drops
Wait2‐3minfortheresult.Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________
Self‐trainingquestions:1. Steran. Cholesterol and cholesterides. Structure, physico‐chemical properties and
biomedicalrole.2. Steroid hormones: glucocorticoids, mineralocorticoids, estrogens, gestagens and
androgens–structureandfunctions.3. Bile acids: cholic, taurocholic and glycocolic acids – structure, properties and
biomedicalrole.
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Casestudy:1. Write the structures of the hydrocarbons from which derive the main classes of
steroids–cholestan,pregnan,androstan,estranandcholan.
2.Writethestructuresanddescribethemainfunctionsofthefollowingsteroidhormones–cortisol,aldosterone,estradiol,progesteroneandtestosterone.
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3. Bile acids are synthesized in the liver cells and conjugatedwith glycine and taurineproducing the the corresponding amides. Write the reactions of glycocholic andtaurocholic acids synthesis. What is the biological significance of bile acidsconjugation?
Testsforself‐assessment:1.Selectthecorrectstatementsregardingcholesterol:
a)istheprecursorofsteroidhormonesb)ishydrophobicc)isastoragelipidd)enterintothecompositionofbiologicalmembranese)istheprecursorofallfat‐solublevitamins
2.Selectthecorrectstatementsaboutthechemicalpropertiesofcholesterol:
a)isanacid b)isasimplelipid
c)isanalcohol d)isanether
e)isanester
3.Choosethecorrectstatementsaboutbileacids: a)contain28carbonatoms b)arenon‐polarcompouns c)aresynthesizedfromcholesterol d)aresynthesizedfromphosphatidicacid e)canemulsifydietaryfats
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4.Indicatebyarrowthecorrectpairs:hormone‐placeofitssynthesis:a)cortisol yellowbodyb)aldosterone ovarianfolliclesc)testosterone cortexoftheadrenalglandsd)estradiol testisLeydigcellse)progesterone
5.Choosethecorrectstatementsaboutcortisol:a)issynthesizedintheliverb)itisaderivativeofpregnanc)isamineralocorticoidd)participatesintheregulationofbloodglucoselevele)contains27carbonatoms
6.Choosetherightstatementsregardingaldosterone:a)itissynthesizedinthecortexoftheadrenalglandsb)itisaderivativeofandrostanec)contains18carbonatomsd)isaglucocorticoide)regulateswaterandelectrolytesmetabolism
7.Regardingprogesterone,thefollowingstatementsaretrue:a)containsanaromaticringb)itissynthesizedintheyellowbodyc)itissynthesizedfromcholesterold)itisusedinmenopausalhormonereplacementtherapye)regulatescarbohydratemetabolism
LESSON№14 Data__________
Fatsolublevitamins–A,D,EandKExperiment№1:IdentificationofvitaminsD(Rosenheimreaction)Method's principle: When vitamins D are treated with concentrated trichloroaceticacid(CCl3COOH)aredcompoundisformed.Thecolorofthecompoundturnsblueintime.Procedure:Putintoatest‐tube:
Reactive VitaminDsol. 5dropsCCl3COOHconc. 5drops
Shakethetest‐tube.Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________
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Experiment№2:IdentificationofvitaminsAMethod's principle: When vitamins A are treated with concentrated trichloroaceticacid(CCl3COOH)ayellowcompound is formed.The colorof the compound turnsblue intime.Procedure:Putintoatest‐tube:
Reactive VitaminAsol. 5dropsCCl3COOHconc. 10drops
Shakethetest‐tube.Rezult:________________________________________________________________________________________________________________________________________________________________________________________________________Conclusion:___________________________________________________________________________________________________________________________________________________________________________________________________
Self‐trainingquestions:1. VitaminsD:cholecalciferolandergocalciferol–structure,synthesisandbiologicrole.2. Calcitriol–structure,synthesisandbiologicrole.3. Isoprenoids. Β‐caroten. Fat soluble vitamins:A, E andK – structure and andbiologic
role.
Casestudy:1.SpecifyschematicallythepathwayofcholesterolconversiontovitaminD3(cholecalciferol).WhatisthebiologicalsignificanceofvitaminD?
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2. Writethestructureofβ‐caroteneandshowthefragmentsof isoprenein itsstructure.Whyisβ‐caroteneorange?
3.Whichcompoundsarecalledcarotenoids?Writethestructureofβ‐caroten,retinoland
retinalandshowtheisoprenefragments.WhatarethefunctionsofvitaminA?
4.Writethestructureanddescribetheroleofα‐tocopherol.
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5.WritethstructuresofvitaminK2anditsstructuralanalog–vicasol.Whatfunctionshavethesechemicalcompounds?
Testsforself‐assessment:
1.Selectthecorrectstatementsaboutfatsolublevitamins: a)allcanbesynthesizedinthehumanorganism b)representativesarefolic,pantothenicandascorbicacids c)representativesarevitaminsA,E,DandK d)aredeliveredbythefood e)arestructuralelementsofthemembranes2.SelectthecorrectstatementsaboutvitaminD: a)issynthesizedintheskinformcholesterol b)theactiveformorthevitaminiscalcitriol c)calcitriolisproducedbydehydrogenationintheliverandkidneys d)thevitamincannotbedepositedinthehumanorganism e)oneofitsfunctionsistoregulatecalciumandphosphatemetabolism
3.ChoosetherightstatementaboutthetransformationofvitaminD:a)vitaminDishydroxylatedintheliverandkidneysb)vitaminDishydroxylatedinmusclesandbonesc)theactiveformofvitaminDiscalcitriold)activeformofvitaminDischolecalciferole)calcitriolissynthesizedintheskinbyhydroxylationofcholesterol
4.Calcitriol–selectthecorrectstatements:a)issynthesizedby2reactionsofhydroxylationofvitaminDintheliverandkidneysb)itisaplantformofvitaminDc)regulatesthelevelofglucoseinthebloodd)regulatesthelevelofsodiumandpotassiuminthebloode)hasananticoagulanteffect
5.SelectthecorrectstatementsaboutvitaminA: a)has2forms–β‐carotenandretinol b)has3forms–retinol,retinalandretinoicacid c)β‐carotenisthevitaminprecursor d)regulatesodiumandpotassiumhomeostasis e)isinvolvedinthevisionprocesses
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6.SelectthecorrectstatementsaboutvitaminE: a)hasantioxidantfunction b)isananticoagulant c)regulatesmineralmetabolism d)hasseveralforms,themostactiveisα‐tocopherol e)isanalcohol
7.SelectthecorrectstatementsaboutvitaminK: a)cannotbesynthesizedinthehumanorganism b)isproducedbythebacteriainthelargeintestine c)hasanticoagulantfunction d)participateinthesynthesisofthecalciumbindingproteins e)vicasolistheplantformofthevitamin
LESSON№15 Data__________
Biologicalmembranes.Chemicalcomposition,structural‐functionalorganization,propertiesandfunctions.Membranetransport
Self‐trainingquestions:
1.Biologicalmembranes.a)Thebiologicalandmedicalroleb)Chemicalcomposition‒lipids,proteins,carbohydrates.Theirfunctionalrole.c)Structuralandfunctionalorganization‒fluid‐mosaicmodelofSinger‐Nicolsond)Thepropertiesofmembranes:fluidity,motility,selectivepermeability,asymmetry,self‐assemblingandself‐repairer.e)Structuralandfunctionaldiversityandspecificity.
2.Membranetransport:a)passivetransport:
‐simplediffusion;‐facilitateddiffusion‐glucosetransporters(GLUT),anionexchangers;‐channeltypealphaandbeta(structuralfeatures).
b)activetransport:‐primary(Na+,K+‐ATPase,Ca2+‐ATPase,ABC‐transporters);‐secondary(aminoacidtransporters,glucose).
c)diseasescausedbydeficiencyofmembranechannelsandtransporters.
Casestudy:1.Writethestructuresofmembranelipidsandshowthepolarandnon‐polarparts.
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2.Listthemonosaccharidesfromtheglycocalix.Whichchemicalbondsappearbetweenthesugarsandproteins?
3.Schematicallyrepresent thebiologicalmembrane– lipidbilayer,periferic, integralandtransmembraneproteins,glicocalix.
4. What are the differences between the cytoplasmic membrane of a normal cell and acancercell?
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Testsforselfassessment:1.Selectthechemicalbondsbetweenthemembraneproteinsandlipids:
a)hydrophobicnteractions
b)ionicbonds c)hydrogenbonds
d)peptidebonds e)disulfidebonds
2. Select the correct statementsabout the carbohydrates inbiologicalmembranes(glycocalix):
a)arelocatedonbothsidesofthemembraneb)bindtolipidsandmembraneproteinsnon‐covalentlyonlyc)haveacatalyticfunctiond)determinetheselectivepermeabilityofthemembranese)areresponsiblefortheintercellularinteractionandadhesion
3. Selectthelipidspresentinbiologicalmembranes:
a) triacylglycerolsb) glycerophospholipidsc) cholesterolesters
d) sphingomyelinse) gangliosides
4. Selectthecorrectstatementsabouttheproteinsofbiologicalmembranes:a) arelocatedonlyintheouterlayeroftheplasmamembraneb) canbeperipheral,integralandtransmembranec) havenomobilityd) performtheroleofintercellularinteractione) canbelinkedbycovalentbondswiththecarbohydratesfromthemembranesurface
5. Selectthesubstanceswhichcrosstheplasmamembranebysodiumsimport:
a) proteinsb) aminoacids
c) triglyceridesd) cholesterol
e)glucose
6.Selectthesubstancesthatpassthroughthemembranebysimplediffusion:
a)waterb)aminoacids
c)Ca2+d)cholesterol
e)CO2
7.Selectsubstancesthataretransportedthroughthecellmembranebytranslocases(facilitateddiffusion):
a)K+b)ammonia
c)triglyceridesd)oxygen
e)glucose
8. Select the substances that are transported through themembrane byATP‐ases(primary‐activetransport):
a)proteinsb)nitrogen
c)H+d)glucose
e)Na+
9. Select the substances thatare transported through the cellmembranewith theparticipationofNa+‐dependenttransports(secondaryactivetransport):
a)proteinsb)aminoacids
c)triglyceridesd)cholesterol
e)glucose
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LESSON№16 Data_________________
ConcludingtestonChapters„Lipids”,„Biologicalmembranes”
1. Biologicalfunctionsoflipids.2. Classification of lipids (structural, functional, according physico‐chemical
properties).3. Saturated and unsaturated fatty acids. Structure, physico‐chemical properties,
representatives.Biomedicalrole.4. Triglycerides‒structure,physico‐chemicalpropertiesandbiomedicalrole.5. Glycerophospholipids:phosphatidylserines,phosphatidylethanolamines(cephalins),
phosphatidylcholines(lecithins),phosphatidylinositols–structure,physico‐chemicalpropertiesandbiomedicalrole.
6. Sphingomyelins‒structure,physico‐chemicalpropertiesandbiomedicalrole.7. Glycolipids: galacto‐ and glucocerebrosides, sulphatides, gangliosides ‒ structure,
physico‐chemicalpropertiesandbiomedicalrole.8. Steran. Cholesterol and cholesterides. Structure, physico‐chemical properties and
biomedicalrole.9. Steroid hormones: glucocorticoids, mineralocorticoids, estrogens, gestagens and
androgens–structureandfunctions.10. Bile acids: cholic, taurocholic and glycocolic acids – structure, properties and
biomedicalrole.11. VitaminsD:cholecalciferolandergocalciferol–structureandbiologicrole.Calcitriol
–structureandbiologicrole.12. Isoprenoids.Β‐caroten.Fatsolublevitamins:A,EandK–structureandandbiologic
role.13. Biologicalmembranes.
a)Thebiologicalandmedicalroleb)Chemicalcomposition‒lipids,proteins,carbohydrates.Theirfunctionalrole.c)Structuralandfunctionalorganization‒fluid‐mosaicmodelofSinger‐Nicolsond)Thepropertiesofmembranes:fluidity,motility,selectivepermeability,asymmetry,self‐assemblingandself‐repairer.e)Structuralandfunctionaldiversityandspecificity.
14. Membranetransport:a)passivetransport:
‐simplediffusion;‐facilitateddiffusion‐glucosetransporters(GLUT),anionexchangers;‐channeltypealphaandbeta(structuralfeatures).
b)activetransport:‐primary(Na+,K+‐ATPase,Ca2+‐ATPase,ABC‐transporters);‐secondary(aminoacidtransporters,glucose).
c)diseasescausedbydeficiencyofmembranechannelsandtransporters.