Protein Synthesis Inhibitors

Question 1

What size ribosomes do bacteria have? What size ribosomes do humans have?

Answer 1

Bacteria: 70s Humans: 80s

Question 2

Aminoglycosides

Answer 2

Type: A Protein Synthesis inhibitor Target 30s subunit of bacterial ribosome: Bactericidal, work on aerobic bacteria Bind irreversably to do one of three things: Block Initiation Stop synthesis Incorporate incorrect Amino Acids Concentration dependent, exhibit postantibiotic effect Synergistic with B-lactams & Vancomycin Resistance: Efflux pumps and Enzymatic acetylation, adenylation, or phosphorylation

Question 3

What is special about Amikacin

Answer 3

Most resistant aminoglycoside to enzymatic modification

Question 4

Tetracyclines

Answer 4

Type: Protein Synthesis inhibitor

Spectrum: Gram+ MRSA Bacteriostatic

Resistence: Efflux pumps, Chemical modification (blockings)

Adverse reactions: Stains teeth, photosensitivity, yeast infections

Question 5

Tigecycline

Answer 5

A modification of glycylcycline that enhances binding and broadens spectrum

Question 6

Macrolides

Answer 6

A Protein Synthesis inhibitor that binds reversibly to 50s to block translocation from A site to P site.

Question 7

Macrolide resistance

Answer 7

Efflux and Reprogramming (similar to vancomycin) a single adenine is methylated and decreases affinity

Question 8

Clyndamycin

Answer 8

A Protein Synthesis inhibitor that works on anaerobes

Question 9

Chloramphenicol (where is it used?)

Answer 9

Not used in America. OTC in South America. Causes bone marrow suppression

Question 10

Oxazolidinoles

Answer 10

A Protein Synthesis inhibitor that binds 50s to prevent the formation of 70s unit. Gram+ only, can be static or cital.

Question 11

Altabax

Answer 11

A Protein Synthesis inhibitor that blocks peptidal transferase. Works well on impetigo.