Lecture 7 & 8 Metabolism

Question 1

What are the principles of the catalase test and the reaction

Answer 1

Most bacteria which are able to grow in the prescence of oxygen are catalase +ve
2H2O2 –> 2H20 + O2

Question 2

What are the principles of the oxidase test and the reaction

Answer 2

Bacteria are oxidase -ve if they lack cytochrome C (enterobacteriaceae lack cytochrome C)

Question 3

What are the principles of the glucose fermentation test

Answer 3

Acids detected by colour change, various pH indicators can be used, must use controls

Question 4

What are the principles of the gas production test and

Answer 4

If bacteria tested produces formic hydrogenylase then hydrogen gas will be produced

Question 5

What are the principles of the oxidation-fermentation test

Answer 5

A test to determine if acid is produced by oxidation (aerobic) and/or fermentation (anaerobically)

Question 6

What are serovars

Answer 6

Bacteria of same species but vary antigenically

Question 7

What are pathovars

Answer 7

Bacteria of same species but vary in diseases caused

Question 8

What is typing

Answer 8

Analysis of bacteria below the species and subspecies level

Question 9

Describe DNA typing (3)

Answer 9

1. Restriction fragment length polymorphism (RFLP) of whole chromosome using electrophoresis
2. Multi locus sequence typing
3. Sequence of whole genome

Question 10

What are the major differences between aerobic and anaerobic (fermentation) metabolism

Answer 10

In aerobic metabolism, the final electron acceptor is oxygen, in anaerobic, the final electron acceptor is an organic molecule