title: Mechanism of penicillin-erythromycin synergy on antibiotic-resistant Staphylococcus aureus.
abstract: Clinically isolated strains of Staphylococcus aureus that are inducibly resistant to both erythromycin and penicillin were susceptible to a combination of the two antibiotics. The synergistic effect of the combination results from an inhibition of penicillinase induction by erythromycin, sparing penicillin and allowing this drug to inhibit growth. When resistance to erythromycin is constitutive rather than inducible, the combination is no longer synergistic.
mesh_terms: D004357:Drug Synergism; D004790:Enzyme Induction / Q000187:drug effects; D004917:Erythromycin / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D010400:Penicillin G / Q000494:pharmacology*; D010403:Penicillin Resistance; D010405:Penicillinase / Q000096:biosynthesis; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000201:enzymology; D065093:beta-Lactamase Inhibitors
chemical_list: D065093:beta-Lactamase Inhibitors; D004917:Erythromycin; D010405:Penicillinase; D010400:Penicillin G
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