Ch 38 - Cell Wall Inhibitors

Question 1

Penicillins:

Answer 1

• most widely effective and least toxic drugs known

Question 2

Penicillin mechanism:

Answer 2

• interfere with the last step of bacterial cell wall synthesis (transpeptidation or cross-linkage), resulting in the exposer of the osmotically less stable membrane. Cell lysis can the occur, either through osmotic pressure or through the activation of autolysins.
• BC and work in time-dependent fashion.
• only effective against rapidly growing organisms that synthesize a peptidoglycan cell wall. mycobacteria, protozoa, fungi and viruses don´t have this structure

Question 3

BC =

Answer 3

bactericidal

Question 4

What are penicillin binding proteins?

Answer 4

• are bacterial enzymes involved in the synthesis of the cell wall and in the maintenance of the morphologic features of the bacterium.
• alterations in some of these PBPs provide the organism with resistance to penicillin