Lecture 33

Question 1

What is Selective toxicity

Answer 1

to kill microbial cells but not the host’s cells

Question 2

What is penicillin

Answer 2

used to destroy staphylococcus bacteria

- interferes with the synthesis of cell wall cross links

Question 3

What are the different inhibitions of antibiotic classes

Answer 3

Inhibition of
cell wall synthesis - penicillin
protein synthesis - aminogylcosides
general metabolic pathway - sulfonamides
DNA or RNA synthesis - actinomycin
disruption of cytoplasmic membrane - polymyxins

special case - inhibition of pathogens attachment or entry into host cell - arildone

Question 4

What is antibiotic resistance

Answer 4

selection of mutants
some bacteria gain resistance to an antibiotic by mutation
some bacteria with resistance survive,
multiply to pass the trait on
creating a resistant bacterial population

Question 5

What is beta-lactamase

Answer 5

an enzyme produced by bacteria and used to destroy penicillin

Question 6

What is vertical gene transfer

Answer 6

some bacteria gain resistance to an antibiotic by mutation
some bacteria with resistance survive,
multiply to pass the trait on
creating a resistant bacterial population

Question 7

What is horizontal gene transfer

Answer 7

bacteria gain resistance by acquiring from external source
bacteria with resistance survive antibiotic
multiply to pass on trait
creates resistant populations

Question 8

How to decrease antibiotic resistance development

Answer 8

-decrease use of antibiotic
improves diagnostics
identify new targets
combination therapy - combine antibiotic with the molecule that blocks resistance mechanisms