Norris S R, Stratton C W, Kernodle D S
Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232.
Antimicrob Agents Chemother. 1994 Jul;38(7):1649-50. doi: 10.1128/AAC.38.7.1649.
Most methicillin-resistant Staphylococcus aureus (MRSA) strains produce beta-lactamase. To determine whether this enzyme(s) is identical to one or more of the four beta-lactamases produced by methicillin-susceptible strains, the beta-lactamases of 50 MRSA isolates were typed by using substrate profile analysis. Forty type A, no type B, ten type C, and no type D beta-lactamase-producing strains were identified. The beta-lactamase inhibitor sulbactam reduced the MICs of beta-lactamase-labile antibiotics, including ampicillin, penicillin G, and cefazolin, for type A and type C MRSA strains.
大多数耐甲氧西林金黄色葡萄球菌（MRSA）菌株可产生β-内酰胺酶。为了确定该酶是否与甲氧西林敏感菌株产生的四种β-内酰胺酶中的一种或多种相同，通过底物谱分析对50株MRSA分离株的β-内酰胺酶进行了分型。鉴定出40株产生A型β-内酰胺酶的菌株，无产生B型β-内酰胺酶的菌株，10株产生C型β-内酰胺酶的菌株，无产生D型β-内酰胺酶的菌株。β-内酰胺酶抑制剂舒巴坦降低了A型和C型MRSA菌株对包括氨苄西林、青霉素G和头孢唑林在内的对β-内酰胺酶不稳定抗生素的最低抑菌浓度（MIC）。
