Department of Plant Sciences, School of Life Sciences, University of Hyderabad, P.O. Central University, Hyderabad 500046, India.
Bacterial Discovery Laboratory, Centre for Environment, Institute of Science and Technology, J. N. T. University Hyderabad, Kukatpally, Hyderabad 500085, India.
Syst Appl Microbiol. 2021 Apr;44(2):126188. doi: 10.1016/j.syapm.2021.126188. Epub 2021 Feb 19.
Two axenic cultures of Planctomycetes were isolated from distinct geographical regions of the east coast of India. The two closely related strains (JC640 and CH01) showed <93.3% 16S rRNA gene sequence identity with members of the genus Roseimaritima followed by Rhodopirellula (<91%). Both strains displayed non-canonical cell morphology of Planctomycetes, such as rod shaped cells with division by lateral budding. Both strains showed crateriform structures on their surfaces and cells lack fimbriae. The genomes have a size of about 5.76 Mb and DNA G+C content of 63.6mol%. Phylogenetic analysis based on 16S rRNA gene sequence and 92 core genes based RAxML phylogenetic tree place both the strains in the family Pirellulaceae and indicated Roseimaritima sediminicola as their closest relative. The AAI and POCP values differentiate both strains from rest of the members of the family Pirellulaceae. The axenic cultures of both strains were able to grow up to 8-10 passages and subsequently the cells became non-viable with pleomorphic shapes. Supported by genomic, phylogenetic and morphological differences, we conclude that both strains belong to a novel genus. However, since the new isolates lost their viability on passaging, we propose the novel genus as "Candidatus Laterigemmans" gen. nov. and the novel species as "Candidatus Laterigemmans baculatus" sp. nov.
从印度东海岸的不同地理区域分离出了两种浮游菌的无菌培养物。这两种密切相关的菌株（JC640 和 CH01）与 Roseimaritima 属的成员具有<93.3%的 16S rRNA 基因序列同一性，其次是 Rhodopirellula（<91%）。两种菌株都表现出浮游菌的非典型细胞形态，例如具有侧芽分裂的杆状细胞。两种菌株的表面都显示出坑状结构，并且细胞没有菌毛。基因组大小约为 5.76 Mb，DNA G+C 含量为 63.6mol%。基于 16S rRNA 基因序列和 92 个核心基因的 RAxML 系统发育树的系统发育分析将两种菌株置于 Pirellulaceae 科中，并表明 Roseimaritima sediminicola 是它们最接近的亲缘关系。AAI 和 POCP 值将两种菌株与 Pirellulaceae 科的其余成员区分开来。两种菌株的无菌培养物都能够生长 8-10 代，随后细胞变得不可存活并具有多形性。基于基因组、系统发育和形态差异，我们得出结论，两种菌株都属于一个新属。然而，由于新分离株在传代过程中失去了活力，我们提出了一个新的属，命名为“Candidatus Laterigemmans”gen. nov.，以及一个新的种，命名为“Candidatus Laterigemmans baculatus”sp. nov.。
