Tomás-Martínez Sergio, Kleikamp Hugo B C, Neu Thomas R, Pabst Martin, Weissbrodt David G, van Loosdrecht Mark C M, Lin Yuemei
Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, 2629 HZ, Delft, The Netherlands.
Microbiology of Interfaces, Department River Ecology, Helmholtz Centre of Environmental Research - UFZ, Brueckstrasse 3A, 39114, Magdeburg, Germany.
Appl Microbiol Biotechnol. 2021 Apr;105(8):3327-3338. doi: 10.1007/s00253-021-11249-3. Epub 2021 Apr 1.
Nonulosonic acids (NulOs) are a family of acidic carbohydrates with a nine-carbon backbone, which include different related structures, such as sialic acids. They have mainly been studied for their relevance in animal cells and pathogenic bacteria. Recently, sialic acids have been discovered as an important compound in the extracellular matrix of virtually all microbial life and in "Candidatus Accumulibacter phosphatis", a well-studied polyphosphate-accumulating organism, in particular. Here, bioaggregates highly enriched with these bacteria (approx. 95% based on proteomic data) were used to study the production of NulOs in an enrichment of this microorganism. Fluorescence lectin-binding analysis, enzymatic quantification, and mass spectrometry were used to analyze the different NulOs present, showing a wide distribution and variety of these carbohydrates, such as sialic acids and bacterial NulOs, in the bioaggregates. Phylogenetic analysis confirmed the potential of "Ca. Accumulibacter" to produce different types of NulOs. Proteomic analysis showed the ability of "Ca. Accumulibacter" to reutilize and reincorporate these carbohydrates. This investigation points out the importance of diverse NulOs in non-pathogenic bacteria, which are normally overlooked. Sialic acids and other NulOs should be further investigated for their role in the ecology of "Ca. Accumulibacter" in particular, and biofilms in general. KEY POINTS: •"Ca. Accumulibacter" has the potential to produce a range of nonulosonic acids. •Mass spectrometry and lectin binding can reveal the presence and location of nonulosonic acids. •The role of nonulosonic acid in non-pathogenic bacteria needs to be studied in detail.
非ulosonic酸（NulOs）是一类具有九个碳骨架的酸性碳水化合物，包括不同的相关结构，如唾液酸。它们主要因其在动物细胞和致病细菌中的相关性而受到研究。最近，唾液酸已被发现是几乎所有微生物生命的细胞外基质中的一种重要化合物，特别是在“聚磷菌聚磷菌”中，这是一种经过充分研究的聚磷积累生物。在这里，使用高度富集这些细菌的生物聚集体（基于蛋白质组学数据约为95%）来研究这种微生物富集物中NulOs的产生。荧光凝集素结合分析、酶定量和质谱分析被用于分析存在的不同NulOs，结果表明这些碳水化合物，如唾液酸和细菌NulOs，在生物聚集体中分布广泛且种类多样。系统发育分析证实了“聚磷菌聚磷菌”产生不同类型NulOs的潜力。蛋白质组学分析表明“聚磷菌聚磷菌”具有重新利用和重新整合这些碳水化合物的能力。这项研究指出了不同NulOs在非致病细菌中的重要性，而这些细菌通常被忽视。唾液酸和其他NulOs尤其应进一步研究它们在“聚磷菌聚磷菌”的生态学以及一般生物膜中的作用。关键点：•“聚磷菌聚磷菌”有产生一系列非ulosonic酸的潜力。•质谱分析和凝集素结合可以揭示非ulosonic酸的存在和位置。•需要详细研究非ulosonic酸在非致病细菌中的作用。
