Lecture 1: Bacterial World

Question 1

Where are bacteria found?

Answer 1

Plants
Animals
Soil
Water
Air
Arctic Ice
Volcanic vents

Question 2

Bacterial habitat in humans

Answer 2

Skin
Teeth
Colon

Question 3

Features of Bacterial Cells

Answer 3

Pilus, Capsule, Cell wall, Plasma membrane, Cytoplasm, Ribosomes, Nucleoid, Plasmid, Flagelli

Question 4

Bacterial Cell Envelope

Answer 4

Cell wall and associated membranes

Question 5

What does Gram-Positive cell envelop consist of?

Answer 5

Thick cell wall and thinner plasma membrane

Question 6

What does a Gram-Negative cell envelope consist of?

Answer 6

Thick outer membrane, thinner cell wall, periplasmic space and thin plasma membrane

Question 7

Peptidoglycan

Answer 7

Provides mechanical strength
Flexible
Sugar glycan chains connected by peptide crosslinks (amino acids)

Question 8

Subunits of glycan chain

Answer 8

2 sugars:
N-acetylmuramic acid (NAM)
N-acetylglucosamine (NAG)

Question 9

Peptide Side Chains

Answer 9

1. L-alanine (most species)
2. D-glutamate (most species)
3. L-diaminopimelic acid (free amino group)
4. D-alanine (never varies)
5. D-alanine (most species)

Question 10

Ways to disrupt cell wall

Answer 10

Lysozyme- hydrolyses every 2nd glycosidic bond

Penicillin- prevents linking 2 side chains together