Microbiologia, Departament de Biologia, Edifici Guillem Colom, Universitat de les, Illes Balears, Campus UIB, 07122 Palma de Mallorca, Spain.
Microbiologia, Departament de Biologia, Edifici Guillem Colom, Universitat de les, Illes Balears, Campus UIB, 07122 Palma de Mallorca, Spain.
Syst Appl Microbiol. 2021 May;44(3):126205. doi: 10.1016/j.syapm.2021.126205. Epub 2021 Apr 21.
Caves are extreme underground environments colonized by oligotrophic bacterial communities that influence mineral transformations. The identification at the species level is important and this study aims to the taxonomic characterisation of four bacterial strains previously isolated from rock surfaces and water samples from a karstic cave located on Mallorca (Spain) that were assigned to the genus Pseudomonas according to 16S rRNA nucleotide sequence analysis. Sequence analysis of the RNA polymerase sigma factor gene (rpoD) allocated these strains to the P. fluorescens lineage within the P. anguilliseptica phylogenetic group, close to the P. benzenivorans type strain. A polyphasic taxonomic approach included phenotypic characterization, fatty acid composition analysis, and whole-cell protein profiling, together with phylogenomic data. The results supported the proposal of a new species in the Pseudomonas genus. Characteristic fatty acid methyl esters of members of the Pseudomonas genus were present (C16:0, C10:0 3-OH, C12:0 2-OH and C12:0 3-OH) and the C12:1 3OH content differentiated these strains from P. benzenivorans. The genomic G + C mol% content of the four sequenced genomes was 66.9%. The average nucleotide indices based on BLAST analysis and the calculation of genome-to-genome distance with respect to their closest relative were lower than 88% and 30%, respectively. These data confirm that the four isolates, R1b-4, R1b-52A, A2bC-1 and R1b-54 represent a new species, for which the name Pseudomonas lalucatii is proposed, with strain R1b-54 as the type strain (=CCUG 74754 = CECT 30179). This is the first species in the P. anguilliseptica group isolated from this extreme habitat.
洞穴是贫营养细菌群落殖民的极端地下环境，这些群落影响着矿物转化。在物种水平上进行鉴定非常重要，本研究旨在对先前从西班牙马略卡岛的喀斯特洞穴中的岩石表面和水样中分离出的四株细菌菌株进行分类学特征描述，根据 16S rRNA 核苷酸序列分析，这些菌株被归为假单胞菌属。RNA 聚合酶 sigma 因子基因（rpoD）的序列分析将这些菌株分配到 P.anguilliseptica 系统发育群中的荧光假单胞菌谱系内，接近 P.benzenivorans 模式株。多相分类方法包括表型特征描述、脂肪酸组成分析、全细胞蛋白图谱分析以及系统基因组学数据。结果支持了在假单胞菌属中提出一个新物种的建议。特征性的假单胞菌属脂肪酸甲酯存在（C16:0、C10:0 3-OH、C12:0 2-OH 和 C12:0 3-OH），这些菌株与 P.benzenivorans 的 C12:1 3OH 含量不同。四个测序基因组的基因组 G+C mol%含量为 66.9%。基于 BLAST 分析的平均核苷酸指数和相对于最近亲缘关系的基因组到基因组距离的计算分别低于 88%和 30%。这些数据证实，四株分离株 R1b-4、R1b-52A、A2bC-1 和 R1b-54 代表一个新物种，建议将其命名为 Lalucatii 假单胞菌，R1b-54 株为模式株（=CCUG 74754=CECT 30179）。这是从这种极端生境中分离出的第一个 P.anguilliseptica 组的物种。
