Pharmacology Lecture 3_Infectiouse diseases: Bacteria

Question 1

What are the 4 indirect virulance factors?

Answer 1

1) Sidrophores (bacterial theft of iron atoms
2) secretion machinery
3) Catalase
4) Regulatory factors

Question 2

What are the three direct virulence factors of bacteria

Answer 2

1) secreted toxins and enzymes
2) capsules
3) cell surface structures

Question 3

What are the three layers that encapsulate a bacteria

Answer 3

The plasma membrane, the cell wall, and the capsule

Question 4

What are the three shapes of bacteria

Answer 4

coccus (spherical), bacillus (rod-shaped), and spiral (twisted)

Question 5

Describe the difference between selective and differential media

Answer 5

selective media will only allow a certain type of bacteria to grow (ie gram negative will grow because the augar is treated with beta lactam anti biotic)

Differential media does not discriminate against what type of bacteria can grow but does have some kind of indication about what sorts of bacteria are present (ie lysing red blood cells in blood augar, color change of the augar in the precense of lactic acid produced by some bacteria)

Question 6

What is a plasmid

Answer 6

A plasmid is a segment of genetic material, seperate from the genome that is found in many bacteria

Question 7

What is peptidoglycan and what is its relevance in gram staining

Answer 7

peptidoglycan is layers of bonded carbohydrates held together by amino acids. It composes essentially the entier cell wall in gram positive bacteria. In gram negative bacteria, it is a component of the cell wall that is inferior to a second plasma membrane