Microbiology and Immunology 2500A/B Lecture Notes - Lecture 19: Minimum Inhibitory Concentration, Streptococcal Pharyngitis, Antimicrobial Resistance

• School: Western University
• Department: Microbiology and Immunology
• Course: Microbiology and Immunology 2500A/B
• Professor: Dr.Summers

Document Summary

Alexander fleming (1881-1955: discovered penicillin in 1928, produced from penicillium the first antibiotic, colo(cid:374)ies of staph(cid:455)lo(cid:272)o(cid:272)(cid:272)i (cid:272)ould(cid:374)"t gro(cid:449) arou(cid:374)d a (cid:272)o(cid:374)ta(cid:373)i(cid:374)ati(cid:374)g (cid:373)old, nobel prize in physiology and medicine (1945) Overuse/misuse of antibiotics: empiric use (blinded use) (cid:862)i"(cid:448)e used this a(cid:374)ti(cid:271)ioti(cid:272) i(cid:374) the past a(cid:374)d it (cid:449)orked, so i"ll just use agai(cid:374)(cid:863, misuse (cid:271)e(cid:272)ause (cid:455)ou"re gi(cid:448)i(cid:374)g drug (cid:455)ou do(cid:374)"t k(cid:374)o(cid:449) (cid:449)ill (cid:449)ork o(cid:374) that (cid:271)a(cid:272)teria. In some serious cases like meningitis, physicians have to do empiric use. Importance is debated: but massive use of anti-biotics in animals produce drug-resistant bacteria that can cause infections in humans. How do antibiotics work: antibiotics either kill bacteria or stop them from growing, for bacteriostatic antibiotics, the immune system must eventually kill the bacteria, bactericidal = killer, bacteriostatic = stopper. Vancomycin: glycopeptide antibiotic, ofte(cid:374) a drug of (cid:862)last resort(cid:863) Bacterial cell wall synthesis: vancomycin binds at d-ala-d-ala block transpeptidation, bacteria switches out target causing resistance.