Antimicrobial Drugs

Chapter 20

I. Chemotherapeutics A. History

– Paul Ehrlich

– Structural analogues» 1935: Domagk

B. General types of chemotherapeutics

1. Structural analogues– competitive inhibitors

– growth factors

2. Antibiotics Chemicals secreted by organisms to kill off

other organisms Primarily isolated from

C. Specificity of various antibiotics

III. Sites of interaction Cell wall

Cell membrane

Essential metabolite biosynthesis

Protein synthesis

DNA replication and transcription

IV. Cell wall inhibitors A. Penicillin family

– Benzylpenicillin

B. Resistance to penicillin

C. Penicillin family:modifications of side chain

Methicillin

Ampicillin

Carbenicillin

Oxacillin

D. Other cell wall growth inhibitors

Cephalosporins

Bacitracin

Vancomycin

V. Inhibitors of protein synthesis Aminoglycosides

Aminoglycosides, cont Tetracyclines

Macrolides

VI. Inhibitors of nucleic acid biosynthesis

Rifamycin

Quinolones

VII. Interaction with plasma membrane

VIII. Viral control Chemical inhibition

Interferon

IX. Fungal control Unique membrane components

Folate biosynthesis

Others block– chitin biosynthesis

– nucleic acid biosynthesis

– microtubule assembly

X. Drug resistance Prevent entry

Alter binding site

Inactivate drug

XI. And in the future. . .