Long Meng, He Qiangcai, Tang Shaoshuai, Gan Zhen, Lu Yishan
Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, and Shenzhen Public Service Platform for Evaluation of Marine Economic Animal Seedings, Shenzhen Institute of Guangdong Ocean University, Shenzhen, Guangdong, China.
Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture, and Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institute, College of Fishery, Guangdong Ocean University, Zhanjiang, Guangdong, China.
Microbiol Spectr. 2025 Mar 31;13(5):e0004125. doi: 10.1128/spectrum.00041-25.
A gram-negative, nitrogen-fixing, rod-shaped, and motile bacterium, designated as ZJS20, was isolated from the sediments of in Zhanjiang, Guangdong, China. The growth of strain ZJS20 occurred at 10°C-45°C, pH 5.5-8.0, and in 0%-3% (wt/vol) NaCl. Strain ZJS20 had the highest sequence similarity of 16S rRNA gene with PCS8 (98.5%), followed by GPTSA-6 (97.1%) and AR1 (96.7%). The phylogenetic trees built using 16S rRNA genes and Type (Strain) Genome Server both revealed that strain ZJS20 fell into a cluster with sp. strains. The genome of strain ZJS20 has a 3,681,671 bp circular chromosome, a G + C content of 62.7%, and 3,320 proteins-coding genes. The genome contains and genes for the synthesis of Mo- and Fe-nitrogenase and genes related to plant growth-promoting traits. Both the digital DNA-DNA hybridization and average nucleotide identity values between strain ZJS20 and type strains of the genus were below the cutoff thresholds for species demarcation. The profiles of the predominant fatty acids, major polar lipids, and respiratory quinone of strain ZJS20 were similar to those of other species. According to the above results, strain ZJS20 is considered to be a novel species of the genus , with the proposed name sp. nov. The type strain is ZJS20 (MCCC 1K08760 = KCTC 8214). This study expands the membership of the genus and reveals the potential of this genus to be used as plant growth-promoting bacteria with their outstanding nitrogen-fixation ability.IMPORTANCE is a genus known as close to the genus and contains only three species, which were isolated from different sources. Except for the physio-biochemical properties, other characteristics, such as genomic information and functions of the genus, have been reported scarcely to date. Here, the study reports the fourth species ( ZJS20) to the genus and reveals its nitrogen-fixation capacity. Comparative genomic analyses revealed that genomes of strain ZJS20 and other type strains all contain genes () for the synthesis of Mo-nitrogenase, as well as genes related to phosphate metabolism and auxin synthesis. Therefore, we proposed that sp. could be considered as a new and potential plant growth-promoting bacteria to be used in agriculture, although in-depth experiments are needed in the future to verify their specific plant growth-promoting traits.
从中国广东湛江的沉积物中分离出一株革兰氏阴性、固氮、杆状且具运动性的细菌，命名为ZJS20。ZJS20菌株在10°C - 45°C、pH 5.5 - 8.0以及0% - 3%（wt/vol）NaCl条件下生长。ZJS20菌株16S rRNA基因与PCS8的序列相似性最高（98.5%），其次是GPTSA - 6（97.1%）和AR1（96.7%）。利用16S rRNA基因构建的系统发育树以及类型（菌株）基因组服务器均显示，ZJS20菌株与[属名]菌株聚为一簇。ZJS20菌株的基因组有一个3,681,671 bp的环状染色体，G + C含量为62.7%，含有3320个蛋白质编码基因。该基因组包含钼固氮酶和铁固氮酶合成相关基因以及与植物促生特性相关的基因。ZJS20菌株与[属名]属模式菌株之间的数字DNA - DNA杂交值和平均核苷酸同一性值均低于物种划分的临界阈值。ZJS20菌株的主要脂肪酸、主要极性脂质和呼吸醌谱与其他[属名]物种相似。根据上述结果，ZJS20菌株被认为是[属名]属的一个新物种，提议命名为[新物种名] sp. nov.。模式菌株为ZJS20（MCCC 1K08760 = KCTC 8214）。本研究扩展了[属名]属的成员，并揭示了该属作为具有出色固氮能力的植物促生细菌的潜力。重要性[属名]属被认为与[另一属名]属关系密切，仅包含三个物种，它们从不同来源分离得到。迄今为止，除了生理生化特性外，该属的其他特征，如基因组信息和功能，鲜有报道。在此，本研究报道了[属名]属的第四个物种（[新物种名] ZJS20）并揭示了其固氮能力。比较基因组分析表明，ZJS20菌株和其他[属名]属模式菌株的基因组均包含钼固氮酶合成相关基因（[具体基因名]）以及与磷代谢和生长素合成相关的基因。因此，我们提议[新物种名] sp.可被视为一种新型且具潜力的植物促生细菌用于农业，尽管未来还需要深入实验来验证其具体的植物促生特性。
