Ye Yu-Qi, Zhang Xin-Yue, Gong Hong-Nan, Ye Meng-Qi, Du Zong-Jun
Marine College, Shandong University, Weihai, Shandong 264209, China.
SDU-ANU Joint Science College, Shandong University, Weihai, Shandong 264209, China.
Syst Appl Microbiol. 2025 Jan;48(1):126575. doi: 10.1016/j.syapm.2024.126575. Epub 2024 Dec 5.
During a study on sediment bacterial diversity in coastal China, three bacterial strains, DH-69, EH-24, and ECK-19, were isolated from coastal sediments off Xiaoshi Island, Weihai. These strains were Gram-staining-negative, aerobic, and coccoid to rod-shaped with prosthecae and flagella. Comparison of the 16S rRNA gene showed that they shared the highest identity values with Hyphococcus flavus MCCC 1K03223 (96.2-97.6 %), followed by Marinicaulis flavus SY-3-19 (95.2-96.8 %) and Marinicaulis aureus HHTR114 (95.2-96.2 %). Genome comparisons using average nucleotide identity (ANI) and average amino acid identity (AAI) suggested that the three novel strains and the three related strains belonged to the same genus, with strains DH-69, EH-24, and ECK-19 identified as two distinct novel species. Pan-genome analysis revealed that 995 core genes were shared among 23 Hyphococcus genomes/MAGs. Secondary metabolites analysis identified a biosynthesis gene cluster for microsclerodermin, a potent antifungal peptide, in the novel strains. Moreover, these newly isolated strains were detected in various ecosystems, with a particular prevalence in marine environments, based on analysis of 500,048 amplicon datasets, underscoring their ecological preference. Based on polyphasic characterizations, strains DH-69 and EH-24 represent a novel species of the genus Hyphococcus, for which the name Hyphococcus formosus sp. nov. is proposed with the type strain DH-69 (= MCCC 1H00436 = KCTC 8010). Strain ECK-19 represents another novel Hyphococcus species, for which the name Hyphococcus lacteus sp. nov. is proposed with the type strain ECK-19 (= MCCC 1H00435 = KCTC 8009). Furthermore, Marinicaulis flavus and Marinicaulis aureus are proposed to be reclassified as Hyphococcus luteus nom. nov. and Hyphococcus aureus comb. nov., respectively, accompanied by an emended description of the genus Hyphococcus.
在中国沿海沉积物细菌多样性研究中，从威海小石岛附近的沿海沉积物中分离出三株细菌，分别为DH-69、EH-24和ECK-19。这些菌株革兰氏染色阴性，好氧，呈球形至杆状，有菌柄和鞭毛。16S rRNA基因比较表明，它们与黄色丝球菌MCCC 1K03223的同源性最高（96.2-97.6%），其次是黄色海茎菌SY-3-19（95.2-96.8%）和金黄色海茎菌HHTR114（95.2-96.2%）。使用平均核苷酸同源性（ANI）和平均氨基酸同源性（AAI）进行的基因组比较表明，这三株新菌株和三株相关菌株属于同一属，其中DH-69、EH-24和ECK-19菌株被鉴定为两个不同的新物种。泛基因组分析显示，23个丝球菌基因组/MAG中共有的核心基因有995个。次生代谢产物分析在新菌株中鉴定出一个用于微硬皮菌素（一种强效抗真菌肽）的生物合成基因簇。此外，基于对500,048个扩增子数据集的分析，这些新分离的菌株在各种生态系统中均有检测到，在海洋环境中尤为普遍，突出了它们的生态偏好。基于多相特征分析，DH-69和EH-24菌株代表丝球菌属的一个新物种，为此提出新名称美丽丝球菌（Hyphococcus formosus sp. nov.），模式菌株为DH-69（= MCCC 1H00436 = KCTC
8010）。ECK-19菌株代表另一个新的丝球菌物种，为此提出新名称乳色丝球菌（Hyphococcus lacteus sp. nov.），模式菌株为ECK-19（= MCCC 1H00435 = KCTC 8009）。此外，建议将黄色海茎菌和金黄色海茎菌分别重新分类为淡黄丝球菌（Hyphococcus luteus nom. nov.）和金黄丝球菌（Hyphococcus aureus comb. nov.），同时对丝球菌属进行修订描述。
