In order to ensure stable performance of engineered biotechnologies that rely on mixed microbial community systems, it is important to identify process-specific microbial traits and study their in-situ activity and responses to changing environmental conditions and system operational parameters. We used BioOrthogonal Non-Canonical Amino acid Tagging (BONCAT) in combination with Fluorescence-Activated Cell Sorting (FACS) and 16S rRNA gene amplicon sequencing to identify translationally active cells in activated sludge. We found that only a subset of the activated sludge microbiome is translationally active during the aerobic treatment phase of a full-scale sequencing batch reactor designed to enhance biological phosphorus removal from municipal wastewater. Relative abundance of amplicon sequence variants was not a reliable predictor of species activity. BONCAT-positive and -negative cells revealed a broad range of population-wide and taxa-specific translational heterogeneity. BONCAT-FACS in combination with amplicon sequencing can provide new insights into the ecophysiology of highly dynamic microbiomes in activated sludge systems.

为了确保依赖于混合微生物群落系统的工程生物技术的稳定性能，重要的是识别过程特定的微生物特征并研究它们的原位活动和对不断变化的环境条件和系统运行参数的响应。我们使用生物正交非规范氨基酸标记 (BONCAT) 结合荧光激活细胞分选 (FACS) 和 16S rRNA 基因扩增子测序来识别活性污泥中的翻译活性细胞。我们发现，在全规模序批式反应器的好氧处理阶段，只有一部分活性污泥微生物组具有转化活性，该反应器旨在增强城市废水中的生物除磷。扩增子序列变异的相对丰度不是物种活动的可靠预测因子。BONCAT 阳性和阴性细胞显示出广泛的群体范围和分类群特异性翻译异质性。