dr. berek zsuzsa - semmelweis...

Antimicrobial chemotherapy

- history

- principles and practice

- mode of action, resistance

Dr. Berek Zsuzsa01 October 2013

How to kill Microbes?

Extracorporal

sterilisation

disinfecting

prevention

Intracorporal

Antimicrobial drugs

chemotherapy

antibiotics

treatment(prevention)

Historical overviewexperimental, „mold-on-bread”

quinine, emetine

Ehrlich 1906 – 1910- Arsphenamines, aniline dyes

(sleeping sickness, trypanosomes)

- 606th drug SALVARSAN

Domagk 1930-s sulphonamides

Fleming 1928 – 1940Penicillin et al.

Waksman 1950-sstreptomycin + aminoglycosides

www.nobelprize.org

„The father of chemotherapy”

1854 - 1915

www.nobelprize.org, www.germannotes.com, www.chemheritage.org www.dw-world.de

aerzteblatt.lnsdata.de, 1909 www.paul-ehrlich-symposium-2004.de

http://www.nobelprize.org/

http://www.germannotes.com/

www.amuseum.de, www.md.ucl.ac.be,

rex.nci.nih.gov

http://www.amuseum.de/

http://www.md.ucl.ac.be/

www.personal.psu.edu, www.jbirc.aist.go.jp

http://www.personal.psu.edu/

www.dhm.de, www.rpsgb.org.uk,

www.personal.psu.edu

www.britannica.com, www.nobelprize.org

http://www.dhm.de/

http://www.rpsgb.org.uk/

http://www.personal.psu.edu/

http://www.britannica.com/


www.uni-muenster.de

www.nobelpreis.org,

www.nobelprize.org

Gerhard Domagk

1895 - 1964

sulfonamides

http://www.nobelpreis.org/


www.britannica.com, clendening.kumc.edu

Nobel prize 1939 (1947)


Sir Alexander

Fleming

1881 - 1955www.nobelprize.org, www.workersforjesus.com

www.gesundheit.de

Penicillin


http://www.workersforjesus.com/

www.nobelprize.org, www.britannica.com

www.asap.unimelb.edu.au

Sir Howard Walter Florey

1898 - 1968

Ernst Boris Chain

1906 - 1979

Nobel prize

1945

Fleming

Florey

Chain



Selman Abraham Waksman

1888 - 1973

… and Fleming

Nobel prize

1952

Streptomycin

Antimicrobial drugs

Chemotherapy- drugs produced in laboratory

Antibiotics- produced by other micro-organism

Principle: selective toxicity (Ehrlich):

Antimicrobial drug should be

toxic to the (pathogen) microbe and

possibly harmless to the host (human being)

Chemotherapeutical index:

dosis tolerata maxima

dosis curativa minima

The drug should be tolerated by the HOST

as high dose as possible, and cure the

HOST as low dose as possible.

Ci=

Kais

er’

s A

bb.

4.2

7

Principles of antimicrobial treatment

HOST

DRUG


correct indication„when to give?”

- in order to: TREAT or AVOID an infection

„what to give?”

the most suitable

1. the most effective one

2. the less toxic one

3. (the cheapest)

Ad 1. effectiveA/ antimicrobial activity

- spectrum = against which species is it effective?

- numerically expressed: MIC, MBC

(minimal inhibitory/bactericidal concentration)

the sensitivity of a bacterium can be

detected in vitro


B/ pharmacokinetic features

selective toxicity (Ad 2.)Side effects: - kidney

- liver

- bone marrow

(- nerves, GI)

C/ resistance


„how much to give”

the satisfactory doseis the multiple amount of MIC at the locus of infection!

Dosage: - age

- liver and kidney functions

- body weight and hight

- pregnancy

„how long to give?” as long as there is no danger of relapseacute infection: min. 5 days

severe infection: 8-14 days

sepsis/endocarditis: 3-4-6 weeks, tbc: 9-12 months


„Magic bullets...”Antibiotic tablets - per os application…

sensitive HALT!

Effect of antimicrobial drugs on bacterium cell

cell wall

membrane

DNA

proteinsynthesis

Antimicrobial drugs

I. Cell wall synthesis inhibitionBeta lactam drugs

1. penicillines

amino-, carboxi-, ureido

and

anti-staphylococcal penicillines

2. cephalosporines

generations: I., II., II., IV.

3. others

(monobactam, carbapenem)

www.med.sc.edu:85

II. Cell membrane destruction

Polymyxin-B and - M

III. Nucleic acid level• Quinolons, fluoroquinolons (gyrase inhibitors)

• metronidazole = Klion®

(DNA damage by toxic metabolites)

Antimicrobial drugs

IV. Protein synthesis inhibition- 30s ribosome subunit

Tetracyclines

Aminoglycosides

- 50s ribosome subunit

chloramphenicol

Macrolides and lincosamides

Erythromycin group and Clindamycin

Oxazolidinones/linezolide (Zyvox®)

Ketolides

Quinupristin-dalfopristin

Antimicrobial drugs

V. Folic acid synthesis inhibitionSulphonamides, trimethoprim

VI. Complex mode of action

Glycopeptides(Vancomycin, Teicoplanin)

1. Cell wall2. Permeability (cell wall - membrane)3. DNA synthesis

Antimicrobial drugs

I. Cell wall synthesis inhibition

Beta lactam drugs

1. penicillines

2. cephalosporines

3. others


II. Cell membrane

destructionPolymyxin-B and - M

III. Nucleic acid level1. Quinolons, fluoroquinolons (gyrase inhibitors)

2. metronidazole = Klion®

(DNA damage by toxic metabolites) www.med.sc.edu:85

Antimicrobial drugs

www.med.sc.edu:85

http://student.ccbcmd.edu/courses/b

io141/lecguide/unit2/control/penres_

fl.html


1. penicillines

2. cephalosporines

3. others


II. Cell membrane

destruction

Polymyxin-B and - M




Antimicrobial drugs

www.med.sc.edu:85

Antimicrobial drugs


1. penicillines

2. cephalosporines

3. others


II. Cell membrane





www.idinchildren.com

Fluoroquinolones – mode of action

Antimicrobial drugs


1. penicillines

2. cephalosporines

3. others


II. Cell membrane





www.crsq.org

Metronidazole – mode of action

TOXIC

Medmicro ch. 11


Tetracyclines

Aminoglycosides


chloramphenicol




Ketolides


Antimicrobial drugs

www.scq.ubc.ca/.../2006/08/protein-

synthesis.gif

Protein synthesis


Tetracyclines

Aminoglycosides


chloramphenicol




Ketolides


Antimicrobial drugs

www.med.sc.edu:85

Initiation of protein synthesis and antibiotics that inhibit initiation


Tetracyclines

Aminoglycosides


chloramphenicol



Streptogramins


Ketolides, Quinupristin-dalfopristin

Antimicrobial drugs

www.med.sc.edu:85

Elongation of proteins and antibiotics that inhibit elongation


Tetracyclines

Aminoglycosides


chloramphenicol



Streptogramins


Antimicrobial drugs

www.chm.bris.ac.uk/motm/linezolid/30s.gif

August 2005 Molecule of the Month

Linezolid

http://www.chm.bris.ac.uk/motm/motm.htm

Mode of action

www.chemsoc.org


Tetracyclines

Aminoglycosides


chloramphenicol



Streptogramins


Ketolides, Quinupristin-dalfopristin

Antimicrobial drugs

Comparison of antibiotic binding sites. (A)

(B) Overview of the binding sites of quinupristin and dalfopristin within the 50S ribosomal subunit, in relation to the P-site tRNA and the ribosomal exit tunnel (highlighted in gold). www.biomedcentral.com

http://www.biomedcentral.com/1741-7007/2/4/figure/F3?highres=y

http://www.biomedcentral.com/1741-7007/2/4/figure/F3?highres=y

V. Folic acid synthesis inhibition

Sulphonamides, trimethoprim

VI. Complex mode of actionGlycopeptides

(Vancomycin, Teicoplanin)

1. Cell wall2. Permeability (cell wall - membrane)3. DNA synthesis

Antimicrobial drugs

www.med.sc.edu:85

Synthesis of tetrahydrofolic acid and antibiotics that inhibit

its synthesis

V. Folic acid synthesis inhibitionSulphonamides, trimethoprim

VI. Complex mode of action

Glycopeptides(Vancomycin, Teicoplanin)

1.Cell wall2.Permeability (cell wall - membrane)3.DNA synthesis

Antimicrobial drugs

Vancomycin – 3D

structure

www.ioc.uni-karlsruhe.de

www.americanchemistry.com

www-personal.umich.edu/

chlorine-containing antibiotic

produced by the soil bacteria, Streptomyces orientalis

chemical formula,

C66H75Cl2N9O2,

shows that it is a

large molecule

"antibiotic of last-resort,"

www.vhcy.gov.tw

www.appdrugs.com/ProdJPGs/VancomycinLg.jpg

www.dundee.ac.uk

http://images.google.hu/imgres?imgurl=http://s

tudent.ccbcmd.edu/courses/bio141/lecguide/u

nit2/control/images/vanresanim.gif&imgrefurl=

http://student.ccbcmd.edu/courses/bio141/lecg

uide/unit2/control/vanres.html&h=278&w=345

&sz=1168&hl=hu&start=108&tbnid=4mNyyhrQ

pMwttM:&tbnh=97&tbnw=120&prev=/images%

3Fq%3Dvancomycin%26start%3D100%26gbv

%3D2%26ndsp%3D20%26svnum%3D10%26

hl%3Dhu%26sa%3DN

http://student.ccbcmd.edu/courses/bio14

1/lecguide/unit2/control/vanres.html

student.ccbcmd.edu/.../images/vanresanim.gif

stu

dent.ccbcm

d.e

du

Antibiotic combinations

Antagonism

A + B = kill each other

Synergism

A + B = D, where D C

Additive

A + B = C,

where C = A + B

Neutral

A + B = A and B

AIMS1. Broaden the spectrum

2. Prevent and/or delay the resistance to develop

3. synergism

Side effectsallergy

- penicillin

dysbacteriosis

candidiasis

Normal flora damage - broad spectrum drugs

direct toxic damage

- aminoglycosides (kidney)

- chloramphenicole (bone marrow)

- tetracyclines (teeth)

- Vancomycin (kidney, „ears”)

Resistance

GENETIC BACKGROUND OF RESISTANCE:

- mutation (chromosome)

- plasmid coded “R” genes

usually both

Tools

Enzymes producedBinding receptor modificationPermeability Efflux pump (active)

Resistance to…

1. Beta lactam drugs2. Macrolides and lincosamides

3. Chloramphenicole = Chlorocid

4. Tetracyclines

5. Aminoglycosides

6. Fluoroquinolones7. Sulfonamides

8. Metronidazole

1.Beta lactam drugs- inhibit the peptidoglycan transpeptidation

Both chromosomal and plasmidbeta lactamase enzyme hydrolysis (beta lactam ring breaks )

trapping beta lactamase + cephalosporin = irreversible complex

amidase and acylase enzymes

altered structure of PBP (penicillin binding protein)

permeability

Resistance to…

beta lactamase enzyme hydrolysis (beta

lactam ring breaks )

www.isrvma.org

permeability enzyme!

www.med.sc.edu:85

www.med.sc.edu:85

Beta lactam antibiotics

Beta lactamase enzyme

Beta - Lactamase Inhibitors

Clavulanic acid Sulbactam TazobactamIn combination with beta lactam drugs

www.isrvma.org

www.javeriana.edu.co

TEM1 beta-lactamase structure

www.antibioresistance.be

ww

w.m

gm

.ufl.e

du/~

gu

lig/b

acge

n/p

g-i

nhib

2.g

if

2. Macrolides and lincosamides et.al

-Alteration of rRNA receptor by methylation

-Efflux

(ketolide)

www.princetoncme.com

3. Chloramphenicol = Chlorocid

enzymatic inactivation

4. Tetracyclines

Permeability

-Ribosome-tRNA stabilisation no inhibition

of protein synthesis

5. Aminoglycosides

- plasmid adenylase, phosphorilase,

acetylase enzymes

inactivation and/or structural changes

Resistance to…

6. Fluoroquinolones- DNA gyrase subunit A change /enzyme mutation/ no

binding

- Permeability- Efflux

www.facm.ucl.ac.be

www.idinchildren.com

7. Sulfonamides- higher affinity to PABA

(enzyme)

- more PABA produced

(mutation)

- inactivation by acetyl-

transferase (plasmid)

8. Metronidazolerarely seen

Resistance to…

AntibioticYear

marketed

Year Resistance

first observed

Sulfonamides 1930 1940

Penicillin 1943 1946

Streptomycin 1943 1959

Chloramphenicol 1947 1959

Tetracycline 1948 1959

Erythromycin 1952 1988

Methicillin 1960 1961

Ampicillin 1961 1973

Cephalosporins 1960s late 1960sPalumbi, S.R. 2001.

Humans as the World's Greatest Evolutionary Force.

Science 293: 1786-1790. www.geo.arizona.edu

www.geo.arizona.edu

Anti-staphylococcal drugs

www.3db.co.uk/media/showcase/cubicin/cubicin2.jpg

www.chem.ubc.ca/.../faculty/scotty/dapto.jpg

Daptomycin

Mode of action:

Cell membrane

depolarisation and

subsequent

inhibition of DNA,

RNA and protein

metabolism

Gram-positive skin infections can now be treated with Cubicin (daptomycin), which is the first of a new class of antibiotics to be approved by the FDA in over two decades.Cubist Pharmaceuticals

www.nature.com/.../v21/n11/images/nbt904-I1.jpg

COSTS OF HUMAN-INDUCED EVOLUTION

IN SOME INSECT PESTS AND DISEASES

Disease/Pest Cost per year

Additional pesticide application $1,200,000,000

Loss of crops $2 - 7,000,000,000

S. aureus Penicillin-resistant $ 2 - 7,000,000,000

S. aureus Methicillin-resistant $ 8,000,000,000

Community-acquired resistant $14 - 21,000,000,000

HIV drug resistance $ 6,300,000,000

Total for these factors $ 33 - 50,000,000,000

Stephen R. Palumbi. 2001. Humans as the world's greatest

evolutionary force. Science 293: 1786-1790. www.geo.arizona.edu

ww

w.g

eo

.arizo

na

.ed

u

THE END

Photo: istvan-istvan

Tele

nd

os,

2005

dr. berek zsuzsa - semmelweis...

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