Beezer A E, Miles R J, Park W B, Smith A R, Brain A P
Microbios. 1986;47(191):117-26.
A mutant of Saccharomyces cerevisiae NCYC 239 with a high minimum inhibitory concentration (35 micrograms ml-1) for nystatin, compared to that of the parent strain (2 micrograms ml-1), was derived by a series of subcultures in media containing increasing antibiotic concentrations. In the absence of nystatin, the growth rate of the mutant was significantly lower than the parent strain, although mean cell-size and size-distribution were similar. No differences between strains were detectable by electron microscopy. Analysis of whole cells showed the total sterol present and the ratio of ergosterol:24(28)dehydroergosterol was similar. However, there were marked differences in amino acid content and chain-length of fatty acids in the cell wall, and protoplasts from resistant cells had decreased amounts of unsaturated fatty acids. It is suggested that alterations in cell wall components in the mutant may be directly linked to the mechanism of nystatin resistance.
通过在含有逐渐增加抗生素浓度的培养基中进行一系列传代培养，获得了酿酒酵母NCYC 239的一个突变体，与亲本菌株相比，它对制霉菌素的最低抑菌浓度较高（35微克/毫升），而亲本菌株的最低抑菌浓度为2微克/毫升。在没有制霉菌素的情况下，突变体的生长速率显著低于亲本菌株，尽管平均细胞大小和大小分布相似。通过电子显微镜未检测到菌株之间的差异。对全细胞的分析表明，存在的总甾醇以及麦角甾醇与24(28)脱氢麦角甾醇的比例相似。然而，细胞壁中氨基酸含量和脂肪酸链长度存在显著差异，抗性细胞的原生质体中不饱和脂肪酸含量减少。有人认为，突变体细胞壁成分的改变可能与制霉菌素抗性机制直接相关。
