Antimicrobials/Vaccination

Question 1

What is bactericidal vs bacteriostatic

Answer 1

bactericidal- the agent kills the bacteria

Bacteriostatic- agent prevents growth of bacteria

Question 2

What is a B lactam antibiotic (general) and ex

Answer 2

Target cell wall

• penicilin
• cepalosporins (cefazolin)
• carbapenems (ertapenem)

Question 3

How do b lactams work (and what class is it considered)

Answer 3

binds to transpeptidase (penicilin binding pro) inactivating it ( cant form peptidoglycan cross links bw nam and nag)

Bactericidal (mostly gram positive bac)

Question 4

What do vancomycins do and how they work (what class they work on)

Answer 4

Attaches to transpeptidase and prevents cross links in cell wall

Bactericidal (Only work on gram positive bac)

Question 5

what do polymyxins target and how (+type of bac)

Answer 5

Target cell membrane

Bind to lipopolysaccharide altering its structure making it more fragile/ leaky

Gram neg bac

Question 6

What do sulphonamides target + enzyme

Answer 6

Impair bacterial metabolism (by inhibiting folate by impairing dihydropteroate synthase)

Bacteriostatic

Question 7

Why dont sulphpnamides affect our own cells

Answer 7

Bact use different enzymes/intermediates to synthesize tetrahydrafolate

Question 8

What do trimethoprims work and what do they target

Answer 8

Bacteriostatic

Blocks folate metabolism via impairment of dihydrofolate reductase

Question 9

What does fluoroquinolones do and target

Answer 9

impair bacterial DNA replication by targeting DNA gyrase and topoisomerases

-can break dna strands

Effective against gram pos and neg bac

Question 10

What do rifamycins do and target

Answer 10

Blocks bacterial transcription by targeting bacterial RNA polymerase

affect gram pos and neg

Question 11

What rifamycins bind to 30s subunit (2)

Answer 11

• Tetracycline- blocks trna(bacteriotatic)

- Aminoglycosides- causes mrna misreading(bactericidal)

Question 12

what rifamycins bind to 50s subunit (3)

Answer 12

-all inhibit peptide bond formation

• Macrolides
• lincosamides
• chloramphenicol

Question 13

What is MRSA resistent to

Answer 13

B lactams

Question 14

What are the 3 mechanisms of antimicrobial resistence

Answer 14

1. Enzymatic degredation of drugs
2. Structural alterations (of cell wall)
3. Efflux pumps etc

Question 15

what does oseltamivir (tamiflu) target

Answer 15

Taregts influenza when trying to leave cell

Will inhibit neuramindase which usually releases virus from cell

Question 16

What do nucleoside analogues do

Answer 16

chemically modified so when then are incorporated into growing nucleotide the replication is terminated

Question 17

Why does nucleoside acylovir only work in infected cells (and what is it an analogue of)

Answer 17

Guanosine analogue

Only works in infected cells as it has to get one phosphate from viral enzyme

Question 18

How does nucleoside reverse transcription inhibitors work (ex of what it works on)

Answer 18

works on HIV

adds AZT into growing DNA chain but since its chem modified it will not elongate

Question 19

What do anifungals typically target

Answer 19

Glucan sysnthesis

Ergosterol sysnthesis

Question 20

what do polyene antifungals do

Answer 20

Bind to ergosterol in cell membrane, which forms pores on plasma membrane

Question 21

What do azoles antifungals do (+ enzyme)

Answer 21

inhibits enzyme used to convert lanosterol to ergosterol

lanosterol 14 a demethylase

Question 22

what do allylamine antifungals do (+ enzyme)

Answer 22

Inhibits squalene epoxidase, one of the 1st enzymes in ergosterol biosynthesis path

Question 23

What do echinocandins antifungals do

Answer 23

inhibit 1,3 b glucan synthase

Question 24

What does metronidazole antiparasitic do

Answer 24

Inhibits nucleic acid synthesis

Question 25

What does artemisinin antimalarial do

Answer 25

use highly reactive free rads that damage membranes and pros

Question 26

how long does a vaccination need to become effective after immunization

Answer 26

2 weeks to generate

Question 27

What are adv and dis of live attenuated vaccinnes

Answer 27

adv- highly immunoenic (mimics natural exposure to pathogen)

Dis- risk of virulence (particulary in indv w weakend immune sys)

Question 28

What are adv and dis of inactivated vaccines

Answer 28

adv- increased saftey

dis- boosters maybe needed, can induce rxns

Question 29

What are subunit vaccines

Answer 29

vacinne containing one or more purified components of a microbe, but not the whole thing

(dont replicate so safe, need adjuvants tho)

Question 30

what are toxoid vaccines

Answer 30

type of subunit vaccine that contain modified or inactivated toxins

(dont replicate and has high saftey profile, need adjuvants tho)

Question 31

how do mrna vacinnes work

Answer 31

mRNAs are packaged into liposoes and put into person.

Expresses viral proteins in person to create antibodies for .