Lee Jae-Young, Li Zhun, Guan Yong, Lee Mi-Kyung
Biological Resource Center, Korean Collection for Type Cultures (KCTC), Korea Research Institute of Bioscience and Biotechnology (KRIBB), Jeongeup, 56212, Republic of Korea.
Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju, 61186, Republic of Korea.
Sci Rep. 2025 Jul 1;15(1):20417. doi: 10.1038/s41598-025-08302-w.
Advancing our understanding of microbial diversity and taxonomy in Korean coast, this study focuses on two intriguing bacterial genera, Marortus and Zhongshania, revealing significant insights through morphological and genomic analyses. The type strain, BJYM1 (= KCTC 92326 = NBRC 115677) was isolated from seawater in Tongyeong, South Korea. BJYM1 was characterized as a Gram-negative aerobic strain with a rod shape and a single polar flagellum. Optimal growth conditions for BJYM1 were identified as 30 °C, pH 6.5, and 0-2% (w/v) NaCl on MA medium. Based on 16S rRNA gene sequence analysis, strain BJYM1 formed a clade with Z. aquimaris CAU 1632, followed by M. luteolus ZX-21 and Z. marina DSW25-10. The phylogenetic relationships of these four strains were also confirmed by genome-based and MALDI-TOF analyses. Strains Z. marina DSW25-10, Z. aquimaris CAU 1632, and BJYM1 possessed a single polar flagellum. The genome of strain BJYM1 had a size of 4.5 Mb with a DNA G + C content of 48.2 mol%. The major respiratory quinone was ubiquinone-8 (Q-8). Major polar lipids included phosphatidylethanolamine (PE), phosphatidylglycerol (PG), and diphosphatidylglycerol (DPG). The major fatty acid was C. Digital DNA-DNA hybridization values between reference strains were notably lower than 70%, with ANI values ranging from 73.31 to 78.57% and AAI values ranging from 75.91 to 83.01%. However, Z. marina DSW25-10 and M. luteolus ZX-21 exhibited dDDH values greater than 70%, as well as ANI and AAI values exceeding 95%. KEGG analysis revealed distinct metabolic pathways between two groups: Group 1 (Z. antarctica DSM 25701, Z. aliphaticivorans SM-2) had high cytochrome c oxidase and transporter: phosphonate pathway activities, while Group 2 (Z. marina DSW25-10, Z. aquimaris CAU 1632, M. luteolus ZX-21, BJYM1) exhibited Sec-SRP, chemotaxis, sulfide oxidation, and sulfur assimilation. BJYM1 displayed unique pathways, including the Cobalt transporter CorA, starch/glycogen synthesis, starch/glycogen degradation, and ferrous iron transporter FeoB. Through comprehensive physiological, phenotypic, and phylogenetic analyses, strain BJYM1 was identified as a new species within the genus Zhongshania, named Zhongshania aquatica sp. nov.
为增进我们对韩国海岸微生物多样性和分类学的理解，本研究聚焦于两个有趣的细菌属，即Marortus和Zhongshania，通过形态学和基因组分析揭示了重要见解。模式菌株BJYM1（= KCTC 92326 = NBRC 115677）从韩国统营的海水中分离得到。BJYM1被鉴定为革兰氏阴性需氧菌株，呈杆状，有一根单极鞭毛。BJYM1在MA培养基上的最佳生长条件为30°C、pH 6.5和0 - 2%（w/v）NaCl。基于16S rRNA基因序列分析，菌株BJYM1与Z. aquimaris CAU 1632形成一个进化枝，其次是M. luteolus ZX - 21和Z. marina DSW25 - 10。基于基因组和MALDI - TOF分析也证实了这四个菌株的系统发育关系。菌株Z. marina DSW25 - 10、Z. aquimaris CAU 1632和BJYM1都有一根单极鞭毛。菌株BJYM1的基因组大小为4.5 Mb，DNA G + C含量为48.2 mol%。主要呼吸醌为泛醌 - 8（Q - 8）。主要极性脂包括磷脂酰乙醇胺（PE）、磷脂酰甘油（PG）和二磷脂酰甘油（DPG）。主要脂肪酸为C。参考菌株之间的数字DNA - DNA杂交值显著低于70%，ANI值在73.31%至78.57%之间，AAI值在75.91%至83.01%之间。然而，Z. marina DSW25 - 10和M. luteolus ZX - 21的dDDH值大于70%，ANI和AAI值超过95%。KEGG分析揭示了两组之间不同的代谢途径：第1组（Z. antarctica DSM 25701、Z. aliphaticivorans SM - 2）具有高细胞色素c氧化酶和转运蛋白：膦酸盐途径活性，而第2组（Z. marina DSW25 - 10、Z. aquimaris CAU 1632、M. luteolus ZX - 21、BJYM1）表现出Sec - SRP、趋化性、硫化物氧化和硫同化。BJYM1展示了独特的途径，包括钴转运蛋白CorA、淀粉/糖原合成、淀粉/糖原降解和亚铁转运蛋白FeoB。通过全面的生理、表型和系统发育分析，菌株BJYM1被鉴定为Zhongshania属内的一个新物种，命名为水生中珊菌（Zhongshania aquatica sp. nov.）
