Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel-Aviv University, Ramat-Aviv, Israel.
FEMS Yeast Res. 2011 Jun;11(4):315-23. doi: 10.1111/j.1567-1364.2011.00722.x. Epub 2011 Feb 21.
We have reported previously that growth on alcohol vapors confers hemolytic properties on certain yeast species and strains ['microbial alcohol-conferred hemolysis' (MACH)]. In a recent study, we analyzed the genetic basis of MACH in Saccharomyces cerevisiae using the EUROSCARF mutant collection. The data suggested that intact mitochondrial and respiratory chain functions are critical for the observed alcohol-mediated hemolysis. We proposed that the uncontrolled cellular uptake of alcohol results in yeast 'hyper-respiration', leading to elaboration of hemolytic molecules such as hydrogen peroxide and lytic lipids. In the current study, we have further analyzed the molecular mechanisms involved in the MACH phenomenon in S. cerevisiae, using DNA microarrays. The patterns of regulation were confirmed by quantitative reverse transcriptase PCR. The results presented here lend further support to this hypothesis, based on upregulation of the genes responsible for coping with vast amounts of hydrogen peroxide produced as a byproduct of excessive oxidation of alcohol. These results, taken together, show that alcohol-mediated hemolysis in yeast appears to be related to the overproduction of hemolytic byproducts, particularly hydrogen peroxide, which accumulates during long-term exposure of S. cerevisiae to both ethanol and n-butanol.
我们之前曾报道过，某些酵母种类和菌株在酒精蒸气上的生长会赋予其溶血特性[微生物酒精赋予的溶血（MACH）]。在最近的一项研究中，我们使用 EUROSCARF 突变体文库分析了酿酒酵母中 MACH 的遗传基础。数据表明，完整的线粒体和呼吸链功能对于观察到的酒精介导的溶血至关重要。我们提出，酒精的不受控制的细胞摄取导致酵母“过度呼吸”，导致溶血分子如过氧化氢和溶脂的产生。在当前的研究中，我们使用 DNA 微阵列进一步分析了酿酒酵母中 MACH 现象涉及的分子机制。通过定量逆转录 PCR 验证了调控模式。这里呈现的结果基于应对大量过氧化氢产生的基因的上调，进一步支持了这一假设，过氧化氢是酒精过度氧化的副产物。这些结果表明，酵母中的酒精介导的溶血似乎与溶血副产物的过度产生有关，特别是在酿酒酵母长期暴露于乙醇和正丁醇时会积累的过氧化氢。
