Chapter 5: Microbial Metabolism

Question 1

Metabolism Def’n

Answer 1

The chemical processes that occur within a living organism in order to maintain life.
- Breaking down of macromolecules, and using the energy to build up different ones

Question 2

Catabolism

Answer 2

Breakdown of macromolecules

1. Degradative
2. Hydrolytic rxn’s (use H2O to break bonds)
3. Exergonic (gives off energy)
4. ATP is produced

Question 3

Anabolism

Answer 3

Constructive metabolism

1. Biosynthetic
2. Dehydration
3. Endergonic
4. Uses ATP

Question 4

ATP

Answer 4

Principle form “metabolic money” can be used, saved, or exchanged.
Adenine - P ~ P ~ P
Bonds are unstable because Phosphates are negatively charged, and like charges repel each other

Question 5

Enzymes

Answer 5

1. A biocatalyst
2. Speeds up the “likelihood of a reaction”
3. Specific for an rxn, but not harmed by the rxn
4. Made of proteins

Question 6

Simple Enzymes

Answer 6

Made of proteins only

Question 7

Conjugated Enzymes

Answer 7

1. Apoenzyme (proteins)
2. Cofactor (nonprotein)
   a. Inorganic (eg, Fe+, Mg+), forms the active site
   b. Organic molecule or coenzymes (eg, vitamin B which is derived from food)

Question 8

Important Coenzymes

Answer 8

Nicotinamide
Adenine
Dinucleotide
Phosphate

Flavin
Adenine
Dinucleotide

Flavin
Mono
Nucleotide

Co A - Coenzyme A
Co Q - Ubiquinone

Question 9

Metabolism Factors

Answer 9

1. Temperature. Increased temp = decreased enzyme activity
2. pH. Bell curve, pH 5 is ideal
3. Substrate. Eventually flattens out because the active sites become saturated
4. Inhibitors
   a. competitive inhibitors occupy the active site.
   eg, PABA – folic acid – yield DNA/RNA
   PABA – sulfanilamide “sulfa drug” interrupts the process – no folic acid – no DNA/RNA – cell death
   b. Allosteric site - used by cells, reversible eg, feedback inhibition