Lampe M F, Minshew B H, Sherris J C
Antimicrob Agents Chemother. 1979 Oct;16(4):458-62. doi: 10.1128/AAC.16.4.458.
Three strains of Enterobacter were studied for their response to ampicillin. They exhibited a basic level of resistance that depended on the medium used and high-level mutational resistance at a frequency of 10(-5) to 10(-7). Two classes of mutants were selected, one of which showed markedly enhanced antibiotic inactivation as indicated by a biological assay and the other of which resembled the wild type in this regard. Both mutants showed cross-resistance to other beta-lactam antibiotics. The results explained discrepancies between traditional broth dilution minimum inhibitory concentration tests and early read automated procedures.
研究了三种肠杆菌菌株对氨苄西林的反应。它们表现出基本的耐药水平，这取决于所使用的培养基，并且以10^(-5)至10^(-7)的频率出现高水平的突变耐药性。选择了两类突变体，其中一类通过生物学测定表明其抗生素失活明显增强，另一类在这方面与野生型相似。两种突变体都对其他β-内酰胺抗生素表现出交叉耐药性。这些结果解释了传统肉汤稀释最低抑菌浓度试验与早期读取自动化程序之间的差异。
