Micro Drugs

Question 1

Cycloserine

Answer 1

Antibiotic- Analog of d serine, will be incorporated into tetra peptides that are attached to the nam molecule. And will inhibit the cross linkage.

Question 2

Bacitracin

Answer 2

it attaches to the carrier molecule so that the carrier molecule can’t pick up a new precursor of nam and nag molecule.

Question 3

Glycopeptides

Answer 3

inhibits the growht fo the cell wall of bacteria. Vancomycin
not effective against Gram -ve because its large size doesn’t allow penetration into the cell.
altered target is a common resistance mechanism

Question 4

Beta Lactams

Answer 4

penicillins and cyclosporins penicillin has a 5 member ring and cephalosporins have a six member ring they attach to the transpeptidases so that crosslinking cannot occur
not effective against mycoplasmas or mycobacteria because they lack cell wall or cell wall is impenetrable.
drug inactivation occurs very commonly, altered uptake and altered target is also common

Question 5

Benzyl penicillin

Answer 5

natural penicillins 1st generation

Question 6

Methicillin

Answer 6

penicillinase resistant penicillins made to resist the penicillinases that bacterias produce

Question 7

Ampicillin

Answer 7

aminopenicillins- 3rd generation, devised to resist acidic ph so you can take it orally

Question 8

Piperacillin

Answer 8

4th generation, same as ampiciliin but has an extended spectrum also active against some gram negative bacteria.

Question 9

Aminoglycosides

Answer 9

induce codon misreading- binds irreversibly to the 30 s subunit which causes the misreading. this means it is bacteriocidal.
Streptomycin
not effective against Anaerobes because oxidative phosphorylation is absent in anaerobes
drug inactivation is a very common resistance mechanism, altered uptake is common, and altered target rare or occurs infrequently.

Question 10

tetracyclines

Answer 10

binds reversibly to the 30s subunit which makes it bacteriostatic, blocks binding of aminoacylated tRNA
Drug inactivation is a common resistance mechanism, altered uptake is an uncommon mechanism.

Question 11

macrolides

Answer 11

erythromycin binds to 23 s and affects polypeptide elongation. ihibits transpeptidation and translocation

Question 12

Lincosamides

Answer 12

will block aminoacylated tRNA from actually attaching to the mRNA and prevents polypeptide formation. target binding at A and P sites

Question 13

Streptogramins

Answer 13

cynacid, dalphopristine, they prevent peptide bond formation. Chloramphenicol

Question 14

Quinolones

Answer 14

Target site is DNA replication, Binds both the alpha subunit DNA gyrase and topoisomerase IV which inhibits DNA synthesis

Question 15

Rifampin

Answer 15

Targets RNA synthesis- binds to Beta subunit DNA dependant RNA polymerase complex and inhibits transcription of mRNA. Is a little toxic to us.

Question 16

Nitroimidazoles

Answer 16

not effective against aerobes becuase it requires activation by flavodoxin which is absent in aerobes.

Question 17

Sulfamethoxazole and Trimethoprim

Answer 17

are metabolism and nucleic acid inhibitors, they act synergistic to prevent formation of tetrahydrofolic acid. Trimethoprim inhibits dihydrofolate reductase and Sulfa inhibits dihydropteroate synthetase prevents conversion to dihydrofolic acid.

Question 18

clavulanic acid

Answer 18

is a beta lactamase inhibitor that you give with penicillin to prevent it being broken down.

Question 19

Polyenes

Answer 19

Direct membrane damage to fungus. these are broad spectrum fungicide

Question 20

Amphotericin B

Answer 20

broad spectrum fungicide, causese direct damage to membrane.

Question 21

5- FC

Answer 21

is a nucleic acid synthesis inhibitor, it can either be incorporated into RNA inhibtion of protein synthesis or can inhibit thymidylate sythetase and inhibit DNA synthesis

Question 22

Azoles

Answer 22

Fluconazole, inhibits aldosterone synthesis so you can make ergosterol

Question 23

Allylamines

Answer 23

lamisil- terbinafine, inhibits squaline epoxidase which means there is an accumulation of squaline and no lanosterol or ergostero formed.

Question 24

Echinocandins

Answer 24

Beta glucan synthesis inhibitors, Caspofungin, Block the B-D-glucan syntheatase, works for Active candida and Aspergillus but not C. Neoformans.