Although MALDI-TOF mass spectrometric analysis has been applied to the characterization of yeast species important in winemaking, relatively few taxa have so far been examined, and the value of low mass peaks for identification has not, to our knowledge, been previously determined. We describe a modified (pre-mixing) procedure for extraction of low (m/z 500-4000) - and high (m/z 2000-20,000) mass range moieties detected by MALDI-TOF and compare it with a previously described, proposed standard method based on a dried-droplet approach. Thirty-three strains representing 21 yeast species were examined. We found our modified method consistently yielded more discriminatory peaks and a broader mass range detection than the proposed standard method for the species examined. Cluster analyses of MALDI-TOF profiles also indicated better separation between species when the pre-mixing method was used, especially where high mass features were used. The use of low mass features may be useful for strain-level discrimination.

中文翻译：

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一种用于葡萄酒相关酵母的MALDI-TOF分析的改进方法。

尽管MALDI-TOF质谱分析已用于表征酿酒中重要的酵母菌种，但到目前为止，已经检查了相对较少的分类单元，据我们所知，用于鉴定的低质谱峰的值先前尚未确定。我们描述了一种改良的（预混合）程序，用于提取通过MALDI-TOF检测到的低（m / z 500-4000）-高（m / z 2000-20,000）质量范围部分并将其与先前描述的拟议方法进行比较基于干滴法的标准方法。检查了代表21种酵母菌的33个菌株。我们发现，与针对所检查物种的建议标准方法相比，我们的改进方法始终可产生更多的鉴别峰和更宽的质量范围检测。MALDI-TOF分布图的聚类分析还表明，当使用预混合方法时，尤其是在使用高质量特征的情况下，物种之间的分离效果更好。低质量特征的使用对于应变水平的判别可能是有用的。