抗微生物药物（英文PPT）Antimicrobial.ppt

Chapter 20 Antimicrobial Drugs Chemotherapy: The use of drugs to treat a disease. Antimicrobial drugs: Interfere with the growth of microbes within a host. Antibiotic: A substance produced by a microbe that, in small amounts, inhibits another microbe. Selective toxicity: A drug that kills harmful microbes without damaging the host. 1928: Fleming discovered penicillin, produced by Penicillium. 1940: Howard Florey and Ernst Chain performed first clinical trials of penicillin. The Action of Antimicrobial Drugs Broad-spectrum Superinfection Bactericidal Bacteriostatic The Action of Antimicrobial Drugs The Action of Antimicrobial Drugs Antibacterial AntibioticsInhibitors of Cell Wall Synthesis Penicillin Natural penicillins Semisynthetic penicillins Penicillins Antibacterial AntibioticsInhibitors of Cell Wall Synthesis Penicillin Penicilinase-resistant penicillins Extended-spectrum penicillins Penicillins + ?-lactamase inhibitors Carbapenems Monobactam Antibacterial AntibioticsInhibitors of Cell Wall Synthesis Antibacterial AntibioticsInhibitors of Cell Wall Synthesis Cephalosporins 2nd, 3rd, and 4th generations more effective against gram-negatives Antibacterial AntibioticsInhibitors of Cell Wall Synthesis Polypeptide antibiotics Bacitracin Topical application Against gram-positives Vancomycin Glycopeptide Important last line against antibiotic resistant S. aureus Antibacterial AntibioticsInhibitors of Cell Wall Synthesis Antimycobacterial antibiotics Isoniazid (INH) Inhibits mycolic acid synthesis Ethambutol Inhibits incorporation of mycolic acid Antibacterial Antibiotics Inhibitors of Protein Synthesis Chloramphenicol Broad spectrum Binds 50S subunit, inhibits peptide bond formation Aminoglycosides Streptomycin, neomycin, gentamycin Broad spectrum Changes shape of 30S subunit Antibacterial AntibioticsInhibitors of Protein Synthesis Tetracyclines Broad spectrum Interferes with tRNA attachment Streptogramins Gram-positives Binds 50S subunit, inhibits translat