Davies E A, Adams M R
School of Biological Sciences, University of Surrey, Guildford, UK.
Int J Food Microbiol. 1994 Mar;21(4):341-7. doi: 10.1016/0168-1605(94)90064-7.
Listeria monocytogenes NCTC 5105 and F6861 were evaluated for sensitivity to nisin. The results confirmed those previously published indicating marked differences in the sensitivity of the two strains. Mutants with increased resistance to nisin could be isolated from the less sensitive F6861 strain at a frequency of 10(-6) to 10(-7). Using a nisin specific enzyme-linked immunosorbent assay, the adsorption of nisin to the different strains and the resistant mutant were studied. At a range of nisin concentrations the amount adsorbed was found to reflect the sensitivity of the strain to nisin, with the more sensitive cells showing greater adsorption. In resistant cells, K+ efflux increased at a slower rate with increasing nisin concentration and had a lower maximum rate indicating that the mechanism of resistance involves a reduction in the accessibility or presence of suitable adsorption sites.
对单核细胞增生李斯特菌NCTC 5105和F6861进行了乳链菌肽敏感性评估。结果证实了先前发表的结果，表明这两种菌株的敏感性存在显著差异。对乳链菌肽耐药性增强的突变体可以从敏感性较低的F6861菌株中以10(-6)至10(-7)的频率分离得到。使用乳链菌肽特异性酶联免疫吸附测定法，研究了乳链菌肽对不同菌株和耐药突变体的吸附情况。在一系列乳链菌肽浓度下，发现吸附量反映了菌株对乳链菌肽的敏感性，敏感性较高的细胞显示出更大的吸附量。在耐药细胞中，随着乳链菌肽浓度的增加，钾离子外流增加的速率较慢，且最大速率较低，这表明耐药机制涉及合适吸附位点的可及性或存在量的减少。
