Antimicrobial agents

Question 1

What are bacteriostatic agents?

Answer 1

inhibitors of protein synthesis - they bind to ribosomes. If concentration of agent is lowered, growth resumes

Question 2

What are bacteriocidal agents?

Answer 2

bind tightly to cells and kill them. Dead cells are not destroyed and total cell numbers remain constant

Question 3

What are bacteriolytic agents?

Answer 3

Kill cells by lysis. Decrease cell number: reduces culture turbidity

Question 4

What are the 2 commonly used assays for measuring antimicrobial activity?

Answer 4

Minimum inhibitory concentration

Disc diffusion assay

Question 5

What is meant by the minimum inhibition concentration?

Answer 5

The smallest amount of agent needed to inhibit the growth of a test bacterium

Question 6

What are common target sites?

Answer 6

Cell wall
Protein synthesis - ribosomes
Nucleic acids - target supercoiling
Cell membrane

Question 7

Disinfectants are used on ______ objects

Answer 7

inanimate

Question 8

Can antiseptics be used on living tissue?

Answer 8

Yes

Question 9

What does the efficacy of biocides depend on?

Answer 9

concentration
microbial load
presence of organic matter

Question 10

Prions are the most susceptible to biocides. True or false?

Answer 10

False - they are the least susceptible

Question 11

Gram ______ are most susceptible to biocides

Answer 11

positive