Data_Sheet_4_Diversity and Ecophysiology of the Genus OLB8 and Other Abundant Uncultured Saprospiraceae Genera in Global Wastewater Treatment Systems.xlsx

The Saprospiraceae family within the phylum Bacteroidota is commonly present and highly abundant in wastewater treatment plants (WWTPs) worldwide, but little is known about its role. In this study, we used MiDAS 4 global survey with samples from 30 countries to analyze the abundance and distribution of members of Saprospiraceae. Phylogenomics were used to delineate five new genera from a set of 31 high-quality metagenome-assembled genomes from Danish WWTPs. Newly designed probes for fluorescence in situ hybridization (FISH) revealed rod-shaped morphologies for all genera analyzed, including OLB8, present mostly inside the activated sludge flocs. The genomes revealed potential metabolic capabilities for the degradation of polysaccharides, proteins, and other complex molecules; partial denitrification; and storage of intracellular polymers (glycogen, polyphosphate, and polyhydroxyalkanoates). FISH in combination with Raman microspectroscopy confirmed the presence of intracellular glycogen in Candidatus Brachybacter, Candidatus Parvibacillus calidus (both from the former genus OLB8), and Candidatus Opimibacter, and the presence of polyhydroxyalkanoates in Candidatus Defluviibacterium haderslevense and Candidatus Vicinibacter. These results provide the first overview of the most abundant novel Saprospiraceae genera present in WWTPs across the world and their potential involvement in nutrient removal and the degradation of macromolecules.

拟杆菌门（Bacteroidota）下的腐螺旋菌科（Saprospiraceae）在全球范围内的污水处理厂（WWTPs）中普遍存在且丰度极高，但目前对其生态功能尚缺乏深入认知。本研究基于覆盖30个国家样本的MiDAS 4全球调查数据集，对腐螺旋菌科各类群的丰度与分布特征展开分析；基于来自丹麦污水处理厂的31条高质量宏基因组组装基因组（metagenome-assembled genomes, MAGs），通过系统发育基因组学方法界定了5个新属。新设计的荧光原位杂交（FISH）探针显示，本次分析涉及的全部菌属（包含原OLB8菌属类群）均呈杆状形态，且大多富集于活性污泥絮体内部。基因组分析揭示了该科类群的潜在代谢功能：可降解多糖、蛋白质及其他复杂大分子，具备部分反硝化能力，还可储存胞内聚合物（糖原、聚磷酸盐与聚羟基脂肪酸酯）。结合荧光原位杂交与拉曼显微光谱技术，研究证实候选类群Candidatus Brachybacter、Candidatus Parvibacillus calidus（二者均原隶属于OLB8菌属）及Candidatus Opimibacter中存在胞内糖原；而Candidatus Defluviibacterium haderslevense与Candidatus Vicinibacter中则含有聚羟基脂肪酸酯。本研究首次全面梳理了全球污水处理厂中丰度最高的新型腐螺旋菌科属类群，及其在营养盐去除与大分子物质降解过程中的潜在作用。