Department of Microbiology, Laboratory of Molecular Bacteriology, University of Calcutta, 35, Ballygunge Circular Road, Kolkata, 700019, India.
Arch Microbiol. 2021 Jul;203(5):2325-2334. doi: 10.1007/s00203-021-02232-7. Epub 2021 Mar 1.
Two novel actinobacteria, strain PSKA28 and PSKA54 were isolated from soil sample of Kashmir-Himalaya, India (latitude 34°-01' N; longitude 74°-47' E; altitude 5328 ft). Polyphasic-taxonomic analysis revealed that these strains belong to the genus Streptomyces. The 16S rRNA gene-sequence similarity of these strain were highest (98.6%) with that of the Streptomyces torulosus NRRLB-3889. They showed 92.1% gyrB gene-sequence similarity but 92.9 and 94.6% rpoB gene-sequence similarity, respectively, with Streptomyces torulosus NRRLB-3889. The sequence similarities were significantly lower than the recommended threshold value for novel taxonomic position and the 16S rRNA sequence-based phylogenetic analysis indicated that these two isolates are in distinct clade. Phylogenomic analysis with their genome sequences, conferred by Type Strain Genome Server separated them from rest of the Streptomyces type strains. The cell wall contained LL-diaminopimelic acid and the whole-cell hydrolysate contained glucose and ribose. Major fatty acid methyl esters were 15:0 anteiso, 16:0 iso and 17:0 anteiso. Average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization (dDDH) values as well as evolutionary distance based on multilocus sequence analysis, between closely related type strains and either of the strain PSKA28 or PSKA54, were considerably lower than the recommended threshold value (< 70% dDDH or < 95-96% ANI/AAI or > 0.007 MLSA distance). Therefore, these isolates represent a novel Streptomyces species, for which we proposed the name Streptomyces himalayensis sp. nov. Genotypic and phenotypic analyses clearly split these strains into two closely related sub-clusters. Based on this, two novel subspecies Streptomyces himalayensis subsp. himalayensis subsp. nov. and Streptomyces himalayensis subsp. aureolus subsp. nov. are proposed, with type strains JCM33755 (= MTCC12933, MCC4145) and JCM33759 (= MTCC12938, MCC4180), respectively.
两株新型放线菌 PSKA28 和 PSKA54 从印度喜马拉雅山的土壤样本中分离出来(纬度 34°-01' N;经度 74°-47' E;海拔 5328 英尺)。多相分类学分析表明,这些菌株属于链霉菌属。这些菌株的 16S rRNA 基因序列相似度最高(98.6%),与链霉菌 torulosus NRRLB-3889 最为接近。它们的 gyrB 基因序列相似度为 92.1%,但 rpoB 基因序列相似度分别为 92.9%和 94.6%,与链霉菌 torulosus NRRLB-3889 最为接近。这些序列相似度明显低于新分类地位的推荐阈值,基于 16S rRNA 序列的系统发育分析表明,这两个分离株处于不同的分支。通过其基因组序列进行的基因组分析,由类型菌株基因组服务器提供,将它们与其他链霉菌类型菌株区分开来。细胞壁含有 LL-二氨基庚二酸,全细胞水解产物含有葡萄糖和核糖。主要脂肪酸甲酯为 15:0 anteiso、16:0 iso 和 17:0 anteiso。与亲缘关系密切的模式菌株相比,PSKA28 或 PSKA54 任一株的平均核苷酸同一性、平均氨基酸同一性和数字 DNA-DNA 杂交(dDDH)值以及基于多位点序列分析的进化距离都明显低于推荐的阈值(<70% dDDH 或<95-96%ANI/AAI 或>0.007 MLSA 距离)。因此,这些分离物代表了一种新型的链霉菌物种,我们提议将其命名为喜马拉雅链霉菌 sp. nov.。基因型和表型分析清楚地将这些菌株分为两个密切相关的亚群。基于此,提出了两个新的亚种喜马拉雅链霉菌亚种喜马拉雅亚种亚种 nov. 和喜马拉雅链霉菌亚种 aureolus 亚种 nov.,其模式菌株分别为 JCM33755(= MTCC12933,MCC4145)和 JCM33759(= MTCC12938,MCC4180)。