1The study of biochemistry is necessary to understand Microbiology

Habitat

Diet

2Why Chemistry?

Conflict between microbe and host.

Vibrio cholera toxin inserting into intestinal cells.

3Terms and Definitions to review and Remember:

• Atom, protons, neutrons, electrons, isotopes, elements, molecules, ions, anions, cations, compounds, covalent bonds, ionic bonds, hydrogen bonds, pH, acids, and bases.

• Solution

•Suspension Andcolloids

4Chemical Reactions

• Synthesis or decomposition reactions– More when we cover metabolism.

• Reactants Products (general)• Substrate(s) Products (enzymatic)

C12H22O11 + H2O 2 C6H12O6

Hydrolysis (left to right) Dehydration (right to left)

+ H2Ohttp://www.unisanet.unisa.edu.au/08365/timages/sucrose.jpg

5Covalent and Hydrogen bonds

Water

Covalent Bonds: sharing of electrons between the oxygen and hydrogen atoms. Strong.

Hydrogen bonds: electrical attraction between electronegative oxygen atom and nearly naked proton. Weak.

mdp2.phys.ucl.ac.uk/ Talks/Ice/Ice.html

6H-bonds hold large molecules together

Example: A-T base pair in DNA

http://www.mun.ca/biology/scarr/Fg10_16a.gif

7Hydrophilic and hydrophobic

Surfaces made of molecules without polar groups (e.g. CH3CH2CH2CH2.) repel water.

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Functional Groups

9Small molecules (monomers) and macromolecules (polymers)

Ethylene and polyethylene

10Carbohydrates: CH2O

Monosaccharides: glucose, fructose, many others

Disaccharides: sucrose, lactose

Oligosaccharides: found on glycoproteins, in cytoplasm (oligo- means “few”)

Polysaccharides: starch, glycogen, agar, chitin, xanthan gum

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14A nucleotide: a monomer of DNA

http://www.emc.maricopa.edu/faculty/farabee/BIOBK/nucleotide.gif

15Nucleic acids are the polymers made from nucleotides.

DNA tRNA

http://www.biochem.uwo.ca/meds/medna/IMG/tRNA.GIF

16The structure of DNA

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Phospholipids are essential building blocks for membranes; sterol-type molecules are rarely found in bacteria.

19A lipid polymer: a biodegradable plastic made by bacteria.

20Inclusions of PHB in a bacterial cell

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