microbiology and antimicrobials

Question 1

Growth conditions for bacteria - terms and define

Answer 1

aerobic = oxygen
capnophillic = carbon dioxide
facultative = with and without oxygen
strictly anaerobic = without oxygen

Question 2

Metronidazole only works on what type of bacteria?

Answer 2

anaerobes

Question 3

How does antimicrobial resistance occur?

Answer 3

when microorganisms, such as bacteria, viruses, fungi and parasites change in ways that render the medications used to cure the infections ineffective

Question 4

how do microbes gain resistance genes?

Answer 4

intrinsic resistance
acquired resistance
- mutation
- acquisition of new DNA

Question 5

mechanisms of antibiotic resistance

Answer 5

altered target site
- changed site = blocked binding
enzyme inactivation
- enzymes destroy antibiotics or prevent binding to target sites
decreased uptake

Question 6

examples of resistance by altered target sites

Answer 6

viridians group streptococci
- e.g. S.mitis
penicillin resistance due to modified penicilin binding proteins

Question 7

examples of resistance by enzyme inactivation

Answer 7

prevotella and fusobacterium species
- resistance mechanism mostly beta lactamases