Supplementary file 1_Insights into the bacterial fraction of sediments from the South China Sea: physiological, chemotaxonomic, and genomic characterization of seven novel members of the Bacillaceae family.docx

The family Bacillaceae is phenotypically and phylogenetically heterogeneous group of bacteria, which has vast metabolic capability in carbohydrates degradation and secondary metabolite production. Deep marine sediments harbor highly diverse microorganisms, playing important roles in ecosystem. Here, we investigated the cultivable fraction of bacteria associated with the sediments of South China Sea (n = 152). After obtaining candidate novel strains, the morphological and physiological characteristics analysis were conducted for polyphasic taxonomy. Additionally, the whole genome sequencing, annotation and comparative genomic analysis were performed for their specific metabolic characteristics. As a result, seven novel members of the family Bacillaceae have been established: Pseudalkalibacillus nanhaiensis sp. nov. (Strain SCS-8T), Paraperibacillus marinus sp. nov. (Strain SCS-26T), Neobacillus oceani sp. nov. (Strain SCS-31T), Paraperibacillus esterisolvens sp. nov. (Strain SCS-37T), Nanhaiella sioensis gen. nov., sp. nov. (Strain SCS-151T), Rossellomorea sedimentorum sp. nov. (Strain SCS-153AT) and Peribacillus sedimenti sp. nov. (Strain SCS-155T). These novel srains display smaller genome sizes and distinctive characteristics. The annotation of Cluster of Orthologous Genes (COG) revealed a higher specific gene abundance in these strains in the carbohydrate transport and metabolism (COG-G), secondary metabolites processes (COG-Q), and the cell membrane-related functions (COG-M). These Bacillaceae species isolated from sediment have different capability to degrade carbohydrates and produce biosynthetic products compared to other reference strains, revealing that they have unique adaptation strategies to the deep marine sediments.

芽孢杆菌科（Bacillaceae）是一类表型与系统发育异质性的细菌类群，具备极强的碳水化合物降解与次生代谢产物合成能力。深海沉积物蕴藏着高度多样的微生物，在生态系统中发挥关键作用。本研究针对南海沉积物（n=152）中的可培养细菌类群展开了调查。在获得候选新菌株后，我们通过多相分类学方法对其形态与生理特征开展了分析；此外，为解析其特殊代谢特征，还完成了全基因组测序、注释以及比较基因组学分析。最终，本研究确立了芽孢杆菌科的7个新类群：南海假碱芽孢杆菌（Pseudalkalibacillus nanhaiensis sp. nov.，菌株SCS-8T）、海洋副类芽孢杆菌（Paraperibacillus marinus sp. nov.，菌株SCS-26T）、海洋新芽孢杆菌（Neobacillus oceani sp. nov.，菌株SCS-31T）、酯解副类芽孢杆菌（Paraperibacillus esterisolvens sp. nov.，菌株SCS-37T）、西奥南海菌（Nanhaiella sioensis gen. nov., sp. nov.，菌株SCS-151T，新属新种）、沉积物罗瑟勒莫雷阿菌（Rossellomorea sedimentorum sp. nov.，菌株SCS-153AT）以及沉积物类芽孢杆菌（Peribacillus sedimenti sp. nov.，菌株SCS-155T）。这些新菌株的基因组尺寸更小，且具备独特的性状特征。直系同源基因簇（Cluster of Orthologous Genes, COG）注释结果显示，相较于其他参考菌株，这些菌株在碳水化合物转运与代谢（COG-G）、次生代谢过程（COG-Q）以及细胞膜相关功能（COG-M）相关基因的丰度显著更高。本次分离自沉积物的芽孢杆菌科菌株与参考菌株相比，在碳水化合物降解与生物合成产物生成能力上存在差异，表明它们对深海沉积物环境具备独特的适应策略。