Pre-separation and pre-concentration of bacteria is an important step especially when they are uncultured and bacterial concentration in the matrix is low. This study describes a preparative method based on isoelectric focusing of colored microorganisms in a cellulose-based separation medium from a high conductivity matrix. The isoelectric points found for the examined cells were 1.8 for Micrococcus luteus, 3.5 for Dietzia sp., and 4.7 for Rhodotorula mucilaginosa using capillary isoelectric focusing. The final positions of the zones of colored microbial cells in the cellulose-bed are indicated by colored pI markers. Segments of the separation medium with cells were harvested by a spatula, simply purified using centrifugation and analyzed by capillary isoelectric focusing and matrix-assisted laser desorption/ionization time of flight mass spectrometry. The determined recovery ranged from 78% to 93%. The viability of the harvested cells was verified by their cultivation.

中文翻译：

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纤维素基分离介质中微生物的制备等电聚焦和 CIEF 和 MALDI-TOF MS 的后续分析

细菌的预分离和预浓缩是一个重要的步骤，尤其是当它们未经培养且基质中的细菌浓度较低时。本研究描述了一种基于纤维素基分离介质中的有色微生物等电聚焦与高电导率基质的制备方法。使用毛细管等电聚焦发现被检查细胞的等电点对于藤黄微球菌为 1.8，对于 Dietzia sp. 为 3.5，对于粘液红酵母为 4.7。纤维素床中彩色微生物细胞区的最终位置由彩色 pI 标记指示。用刮刀收集含有细胞的分离培养基片段，使用离心进行简单纯化，并通过毛细管等电聚焦和基质辅助激光解吸/电离飞行时间质谱法进行分析。确定的回收率范围为 78% 至 93%。收获的细胞的活力通过它们的培养来验证。