antibiotics

Question 1

52% of antibiotic produced world wide are

Answer 1

B-lactam

Question 2

24% are

Answer 2

fluroquinolones

Question 3

20% are

Answer 3

macrolides

Question 4

eukaryotes- fungi

Answer 4

Azores, allylamines, cycloheximides, polymers, polyoxins, nucelic acid, analogs, echinocandins

Question 5

viruses

Answer 5

nonnucleodise reverse transcriptase inhibitors.

Protease inhibitors. Nucleoside analogs interferons

Question 6

why do some antibiotics cause adverse side effects

Answer 6

act on similar eukaryotic structures and processes e,g, translation

Question 7

Vancomycin

Answer 7

inhibits cell wall biosynthesis. Poor bioavailability–> used to treat C.difficile

Question 8

Methicillin

Answer 8

inhibits cell wall synthesis similarly to penicillin- no longer used

Question 9

R plasmid

Answer 9

consists of a resistance transfer factor that enables conjugate and contains genes conferring resistance
–>Resistance transfer factor (shortened as R-factor or RTF) is an old name for a plasmid that codes for antibiotic resistance.

Question 10

antibiotics are

Answer 10

naturally occurring antimicrobials: antibiotics

Question 11

modification of natural antibiotics results in

Answer 11

semi-synthetic antibiotics

Question 12

natural penicillin

Answer 12

Benzylpenicillin - gram positive activity

-B-lactamase-sensitive

Question 13

semisynthetic penicillins

Answer 13

Methicillin- acid stable and B-lactamase resistant
Oxacillin-acid stable- B lactamase resistant
Ampicillin- acid stable and B-lactamase-sensitive (broadened spectrum of activity)

Question 14

tetracycline is produced by

Answer 14

Streptomycin rimosus

Question 15

penicillin is produced by

Answer 15

Penicillium chrysogenum

Question 16

streptomycin is produced by

Answer 16

Stremptomyces griseus

Question 17

almost all pathogens have

Answer 17

acquired resistance to some chemotherapeutic agents

Question 18

a few pathogens have

Answer 18

developed resistance to all know antimicrobial agent - MRSA

Question 19

use of antibiotics in medicine, veterinary medicine and agriculture’s selects for the

Answer 19

spread of R plasmid

Question 20

way pathogens can be resistant to bacteria

Answer 20

1) organism lacks structure the antibiotic inhibits
2) organism is impermeable to antibiotic
3) organism can inactivate the antibiotic
4) organism may modify the target of the antibiotic
5) organism may be able to pump out the antibiotic- efflux

Question 21

aminoglycosides

Answer 21

are antibiotics that contain amino sugars bonded by glycosidic linkage. Not commonly used today duet neurotoxicity and nephrotoxicity–> considered reserved antibiotics for when others fails

Question 22

Macrolides

Answer 22

contain lactone rinds bonded to sugars. Broad spectrum –> targets 50 s subunit in ribosomes

Question 23

tetracyclines

Answer 23

contain four rings. Widespread medical use in humans and animals.Broad spectrum and inhibits protein synthesis. Inhibits functioning of 30s ribosomal subunit

Question 24

synthetic anti-microbial drugs: QUINOLONESi

Answer 24

inhibition of DNA gyrate. Binds tot he A subunit of DNA gyrate (A2B2). Resistance mediated by decreased binding

Question 25

B-lactam

Answer 25

one of the most important groups of anti bionics ever. Includes penicillins, cephalosporins and cephamycins. ver half the antibiotics used worldwide.

Question 26

penocllins are primarily effective against

Answer 26

gram positive bacteria. some synthetic dorms are effective against Gram-neg bacteria.
Targets cell wall synthesis