Kirdat Kiran, Patwekar Umera, Jain Kunal, Mubarak Malad, Choudhary Pradeep, Thakkar Lucky, Thorat Vipool, Madamwar Datta, Lodha Tushar, Yadav Amit
National Centre for Cell Science, National Centre for Microbial Resource, University of Pune Campus, Ganeshkhind, Pune, 411007, India.
Post Graduate Department of Biosciences, Sardar Patel University, Anand, 388315, India.
Antonie Van Leeuwenhoek. 2025 May 26;118(6):82. doi: 10.1007/s10482-025-02093-w.
A novel Gram-stain-negative, aerobic rod-shaped bacterial strain, which was catalase- and oxidase-positive, designated as DMV24BSW_D, was isolated from the estuarine waters of the Bhavnagar (India) coast of the Arabian Sea. Its 16S rRNA gene exhibited 99.52% similarity with Neopusillimonas maritima 17-4A, followed by 97.95% similarity with the Pusillimonas caeni strain EBR-8-1 and 97.4% similarity with the P. noertemannii strain BN9. Phylogenomic analysis using BPGA (14,332 aa) and UBCG (90,261 bp) tools revealed a unique phylogenetic position within the genus Neopusillimonas. The genome exhibited a G + C content of 53.25%. In comparison with N. maritima 17-4A, the strain demonstrated an average nucleotide identity (ANIb) of 94.47% and a digital DNA-DNA hybridization (dDDH) value of 60.1%, indicating distinct genomic divergence. The genome of DMV24BSW_D contains several unique metabolic genes that facilitate efficient electron transfer during aerobic respiration. Additionally, it harbours one intact prophage and four defective prophages, indicating ongoing viral interactions. The genome encodes a complete pathway for ectoine biosynthesis and transportation. Strain DMV24BSW_D tested positive for gelatin hydrolysis and demonstrated the ability to utilize a wide range of carbohydrates, including α-D-glucose, D-melibiose, D-fructose, L-rhamnose, and various organic acids, such as methyl pyruvate and propionic acid, along with tolerance to fluctuating pH (5 to 10) and salinity (0-4% NaCl). The major polar lipids included phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylethanolamine, while fatty acid analysis revealed C, C, C cyclo, and summed feature 2 (C aldehyde/unknown) as major components. The respiratory quinones identified were MK-7 and MK-8. These comprehensive phenotypic, chemotaxonomic, and genomic characteristics support the unique taxonomic position of DMV24BSW_D within the genus Neopusillimonas and the proposal of a novel species of the genus Neopusillimonas, for which the name Neopusillimonas aestuarii sp. nov. (Type strain DMV24BSW_D = MCC 2506 = KCTC 72453 = JCM 34508) is proposed.
从阿拉伯海印度巴夫那加尔海岸的河口水中分离出一种新型革兰氏阴性需氧杆状细菌菌株，该菌株过氧化氢酶和氧化酶呈阳性，命名为DMV24BSW_D。其16S rRNA基因与海洋新希瓦氏菌17 - 4A的相似性为99.52%，其次与淡水新希瓦氏菌菌株EBR - 8 - 1的相似性为97.95%，与诺氏新希瓦氏菌菌株BN9的相似性为97.4%。使用BPGA（14,332个氨基酸）和UBCG（90,261 bp）工具进行的系统基因组分析揭示了该菌株在新希瓦氏菌属内的独特系统发育位置。该基因组的G + C含量为53.25%。与海洋新希瓦氏菌17 - 4A相比，该菌株的平均核苷酸同一性（ANIb）为94.47%，数字DNA - DNA杂交（dDDH）值为60.1%，表明存在明显的基因组差异。DMV24BSW_D的基因组包含几个独特的代谢基因，有助于有氧呼吸过程中的高效电子传递。此外，它含有一个完整的原噬菌体和四个缺陷原噬菌体，表明存在正在进行的病毒相互作用。该基因组编码了一条完整的依克多因生物合成和运输途径。菌株DMV24BSW_D明胶水解试验呈阳性，能够利用多种碳水化合物，包括α - D - 葡萄糖、D - 蜜二糖、D - 果糖、L - 鼠李糖，以及各种有机酸，如丙酮酸甲酯和丙酸，同时耐pH值波动（5至10）和盐度（0 - 4% NaCl）。主要极性脂包括磷脂酰甘油、双磷脂酰甘油和磷脂酰乙醇胺，而脂肪酸分析显示C、C、C环和总和特征2（C醛/未知）为主要成分。鉴定出的呼吸醌为MK - 7和MK - 8。这些全面的表型、化学分类和基因组特征支持了DMV24BSW_D在新希瓦氏菌属内的独特分类地位，并提议将其作为新希瓦氏菌属的一个新物种，命名为河口新希瓦氏菌（Neopusillimonas aestuarii sp. nov.）（模式菌株DMV24BSW_D = MCC 2506 = KCTC 72453 = JCM 34508）。
