Exam 3 - Part 2

Question 1

minimal inhibitory concentration

Answer 1

lowest concentration of a drug that inhibits growth of pathogen

Question 2

mode of action of penicillin

Answer 2

• inhibition of the last step (transpeptidation) in bacterial cell wall synthesis
• acts only on growing bacteria that are synthesizing new peptidoglycan

Question 3

what percentage of adults in the U.S. are allergic to penicillin?

Answer 3

1-5%

Question 4

cephalosporin

Answer 4

structurally and functionally similar to penicillin, broad sprectum antibiotics given to those who are allergic to penicillin

Question 5

what enzyme is produced by penicillin resistant bacteria?

Answer 5

penicillinase

Question 6

vancomycin

Answer 6

• glycopeptide antibiotics
• inhibit cell wall synthesis by blocking transpeptidation
• important for treating antibiotic resistant staphylococcal and enterococcal infections
• used as a last resort

Question 7

protein synthesis inhibitors

Answer 7

• many will bind to the 30S or 50S ribosomal subunit

- other can bind to aminoacyl tRNA binding, peptide bond formation, mRNA reading, and translocation

Question 8

what are metabolic antagnonists?

Answer 8

structural analogs

Question 9

sulfa drugs

Answer 9

PABA analog

- precursor for folic acid

Question 10

trimethoprim

Answer 10

• a synthetic antibiotic that also interferes with folic acid production

Question 11

blocking DNA replication

Answer 11

• inhibition of DNA polymerase and helicase

Question 12

modes of administration for microbial drugs

Answer 12

oral, topical, parenteral routes

Question 13

what are some hurdles for antimicrobial drugs?

Answer 13

blood clots or necrotic tissue

Question 14

efflux pump

Answer 14

pump drug out of system

Question 15

drug inactivation

Answer 15

chemical modification of drug by pathogen

Question 16

where can resistance be found?

Answer 16

bacterial chromosomes, plasmids, transposons

Question 17

amantadine

Answer 17

• anti-viral
  used to prevent some types of flues
• blocks penetration and uncoating

Question 18

tamiflu

Answer 18

anti viral
anti-influenza
- neuraminidase inhibitor
- shorten course of disease

Question 19

acyclovir

Answer 19

antiviral

inhibit herpes infection

Question 20

chloroquine and mefloquine

Answer 20

anti-protozoa

malaria

Question 21

metronidazole

Answer 21

anti-protozoa

entamoeba infections

Question 22

polyenes

Answer 22

anti-fungal
bind to sterol, disrupts cell membrane function
- amphotericin B and nystatin

Question 23

azoles

Answer 23

anti-fungal
block ergosterol synthesis
inhibits cell membrane synthesis
- miconazole

Question 24

archaea

Answer 24

• highly diverse in morphology, physiology, reproduction, and ecology
• extremophiles
  classified based on physiological and morphological differences
• cell wall of pseudomurein

Question 25

how are archaea groups differed

Answer 25

glucose catabolism, CO2 fixation, and synthesize methane

Question 26

extreme halophiles

Answer 26

• require atleast 1.5 M NaCL
• cell wall disinigrates if not
• aerobic chemoheterotrophs with complex nutritional requirements

Question 27

extreme thermophiles

Answer 27

• optimal growth temps around 88-100 C
• sulfure metabolizing microorganisms
• isolated from marine hydrothermal vents

Question 28

other extremophiles

Answer 28

• acidophilic

- alkalylophilics

Question 29

microbial ecology

Answer 29

the study of community dynamics and the
interaction of microbes with each other, with
plants and animals, and with the environment in
which they live

Question 30

how many microbes have been cultured, identified, and studied?

Answer 30

1%

Question 31

biogeochemical cycling

Answer 31

the study of community dynamics and the
interaction of microbes with each other, with
plants and animals, and with the environment in
which they live

Question 32

what is the primary concern regarding safety of drinking water?

Answer 32

gastrointestinal pathogens