Anti-bacterial

Question 1

Ampicillin

Answer 1

Extended spectrum penicillin
B-lactam antibiotic
Mimics peptide bond between terminal D-Ala D-Ala on the pentapeptide - pseudo substrate for transpeptidase

Question 2

Methicillin

Answer 2

Narrow spectrum (gram +ve) B-lactamase resistant penicillin
B-lactam antibiotic
Mimics peptide bond between terminal D-Ala D-Ala on the pentapeptide - pseudo substrate for transpeptidase

Question 3

Penicillin

Answer 3

B-lactam antibiotic

Mimics peptide bond between terminal D-Ala D-Ala on the pentapeptide - pseudo substrate for transpeptidase

Question 4

Cephalosporin

Answer 4

B-lactam antibiotic
Mimics peptide bond between terminal D-Ala D-Ala on the pentapeptide - pseudo substrate for transpeptidase
But rather than B-Lactam ring = thiazalidine ring

Question 5

Monobactam

Answer 5

B-lactam antibiotic

Mimics peptide bond between terminal D-Ala D-Ala on the pentapeptide - pseudo substrate for transpeptidase

Question 6

Carbapenem

Answer 6

B-lactam antibiotic

Mimics peptide bond between terminal D-Ala D-Ala on the pentapeptide - pseudo substrate for transpeptidase

Question 7

Vancomycin

Answer 7

Binds to D-Ala D-Ala on pentapeptide terminal and prevents access for transpeptidase
Susceptible to osmotic disturbances

Question 8

Bacitracin

Answer 8

Inhibits bactoprenol regeneration to transport peptidoglycan precursors

Question 9

Cycloserine

Answer 9

Inhibits D-Ala D-Ala joining pentapeptide

Question 10

Fosfomycin

Answer 10

Inhibits pyrual transferase inhibiting the production of N-acety Utp murayl tripeptide… Preventing pentapeptide formation

Question 11

Isoniazid

Answer 11

Inhibits mycolic acid synthesis - envelope of mycobacterium tuberculosis
Limited spectrum

Question 12

Tetracycline

Answer 12

Polykietic broad spectrum, bacteriostatic antibiotic
Targets 30s Ribosome subunit, reversibly binds and inhibits amino-actyly tRNA entrance into the A site
Can form Ca + Mg complexes reducing bioavailability and stripping enamel and bone, also reduces intestinal flora
First drug agains Mycoplasma and Cholera

Question 13

Spectinomycin

Answer 13

Polykietic bacteriostatic antibiotic

Targets the 30s Ribosomal subunit

Question 14

Streptomycin

Answer 14

Aminoglycoside, bacteriocidal antibiotic
Acts on 30s ribosome subunit, prevents / freezes the pre-initiation complex (bacteriostatic), slows translation, and reduced fidelity of amino acid matching by inducing miss-reading of the RNA
Narrow spectrum for Gram -ve Rods
Increase mucus production

Question 15

Gentomycin

Answer 15

Less toxic version of streptomycin, aminoglycoside antibiotic, acts on 30s Ribosome subunit, prevents formation of pre-initiation complex, slows translation and induces miss-reading into the RNA reducing fidelity of matching
Narrow spectrum for Gram -ve Rods
Increase mucus production

Question 16

Erthyromycin

Answer 16

Naturally occurring macrolide, narrow spectrum (gram +ve) antibiotic
Targets the 50s ribosomal subunit
Binds to the entrance of the polypeptide exit tunnel preventing further elongation
Short elimination half life and reduced bioavalibility

Question 17

Azithromycin

Answer 17

Macrolide antibiotic, extended spectrum

Targets 50s Ribosome subunit, binds to entrance of polypeptide exit tunnel and prevents further elongation

Question 18

Clarithromycin

Answer 18

Macrolide antibiotic, extended spectrum

Targets 50S Ribosomal subunit, binds to entrance of polypeptide exit tunnel and prevents further elongation

Question 19

Chloramphenicol

Answer 19

Macrolide broad spectrum antibiotic
Targets 50s Ribosome subunit and prevents peptidyl-transferase activity
Extremely hydrophobic therefore rapid onset of action and can cross BBB, used in treatment of bacterial meningitis
Limited used - bone marrow suppression

Question 20

Fusidic Acid

Answer 20

Narrow spectrum for Gram +ve

Inhibits protein synthesis by inhibiting elongation factor G which is required for peptide translocation

Question 21

Ciprofloxacin

Answer 21

Quinolone broad spectrum Antibiotic
Inhibits DNA replication
Targets GryA (ATP domain) of Type II Topoisomerase -stabilises the intermediated therefore holds double cleaved DNA
Used against Anthrax and psuedomonas

Question 22

Levofloxacin

Answer 22

Quinolone, narrow spectrum (gram +ve) Antibiotic
Inhibits DNA replication
Targets GryA of Type II topoisomerase -stabilises the intermediated therefore holds double cleaved DNA
Used against Streptococcus pneumonia

Question 23

Coumermycin A1

Answer 23

Aminocoumarin antibiotic
Inhibits DNA replication
Targets GryB (DNA binding domain) of Type II topoisomers - stabilises the intermediated therefore holds double cleaved DNA

Question 24

Novobiocin

Answer 24

Anticoumerin Antibiotic
Inhibits DNA replication
Targets GryB of type II topoisomerase - stabilises the intermediated therefore holds double cleaved DNA

Question 25

Rifampin

Answer 25

Inhibits RNA sysnthesis - binds to B subunit of DNA dependent RNA polymerase and prevents elongation, alos binds to RNA transport tunnel and prevents exit Used against mycobacterium tuberculosis

Question 26

Bleomycins

Answer 26

Also used in Cancer therapy, metal chetalating glycoprotein agent, interacts with iron close to DNA creating free radicals which act to fragment DNA by acting on phosphodiesterase backbone

Question 27

Daunomycin

Answer 27

Also used in cancer therapy, non-covalently interacts with the DNA, intercalates between strands disrupting major and minor grooves

Question 28

Mitomycin C

Answer 28

Covalently interacts with the DNA, alkylating agent, causes cross-links between guanine residues preventing strand separation Must be reduced before action therefore selective to hypoxic environments - tumour !

Question 29

Co-Trimoxazole

Answer 29

Combination of sulfamethoxazole and trimethoprim, inhibits folic acid synthesis

Question 30

Sulfamethoxazole

Answer 30

Anti-metabolite, inhibits di-hydropterate synthase essential in folic acid synthesis

Question 31

Trimethoprim

Answer 31

Anti-metabolite, inhibits dihyrodfolate reductase essential in folic acid synthesis

Question 32

Valinomycin

Answer 32

Peptide antibiotic Targets cell membrane - very hydrophobic, acts to form circular structures in membrane which function as K+ uniporters, disrupts membrane potential, and signalling Lack of specificity for bacteria

Question 33

Gramicidin A

Answer 33

Peptide antibiotic Targets cell membrane - dimerises at surface and forms transmembrane ion channel for monovalent cations, disrupting membrane potential, movement of H+ also disrupts pH and proton gradient Limited specificity for bacteria

Question 34

Polymixin E

Answer 34

Targets Gram -ve bacterial cell envelope, makes envelope leaky to ions Extremely +ve therefore targets Lipid A Used in treatment of multi drug resistance

Question 35

Nystatin

Answer 35

Forms ion channels within ergosterol cell membrane, mainly found on Fungi

Question 36

Amphotericin B

Answer 36

Forms ion channels within the ergosterol cell membrane, mainly found on fungi

Question 37

Fluconazole

Answer 37

Targets Ergosterol biosynthesis