Bonfiglio G, Livermore D M
Department of Medical Microbiology, London Hospital Medical College, UK.
J Antimicrob Chemother. 1991 Dec;28(6):837-42. doi: 10.1093/jac/28.6.837.
The susceptibility of Xanthomonas maltophilia strains to beta-lactams was shown to depend on the concentrations at which individual media were prepared. MIC and disc susceptibility tests were performed on solidified Mueller-Hinton and Iso-Sensitest media prepared at 0.1, 0.3, 1, and 3 x the concentrations recommended by the manufacturers. Nine of ten X. maltophilia strains tested showed increasing sensitivity to meropenem, cefotaxime, cefoperazone, piperacillin and latamoxef as the nutrient concentrations of the two media were increased. The opposite pattern was found with one strain (NCTC 10257) on Mueller-Hinton agar. This strain behaved inconsistently on Iso-Sensitest agar. Previous studies have shown that medium-dependent susceptibility in X. maltophilia is not related to beta-lactamase expression. The present study demonstrated that 22 and 25 kDa outer membrane proteins were induced on media with higher nutrient concentrations. The possible relationship of these proteins to sensitivity is considered.
嗜麦芽窄食单胞菌菌株对β-内酰胺类药物的敏感性显示取决于制备各个培养基时的浓度。在按照制造商推荐浓度的0.1、0.3、1和3倍制备的凝固穆勒-欣顿培养基和异感测培养基上进行了最低抑菌浓度（MIC）和纸片药敏试验。在测试的10株嗜麦芽窄食单胞菌菌株中，有9株随着两种培养基营养浓度的增加，对美罗培南、头孢噻肟、头孢哌酮、哌拉西林和拉氧头孢的敏感性增加。在穆勒-欣顿琼脂上，一株菌株（NCTC 10257）呈现相反的模式。该菌株在异感测琼脂上表现不一致。先前的研究表明，嗜麦芽窄食单胞菌中培养基依赖性敏感性与β-内酰胺酶表达无关。本研究证明，在营养浓度较高的培养基上会诱导产生22 kDa和25 kDa的外膜蛋白。考虑了这些蛋白与敏感性之间的可能关系。
