Key Laboratory of Microbial Diversity in Southwest China, Ministry of Education, Yunnan Institute of Microbiology, Yunnan University, Kunming 650091, PR China.
Department of Life Sciences and Technology, Xinxiang Medical University, Xinxiang 453003, PR China.
Int J Syst Evol Microbiol. 2014 Sep;64(Pt 9):2998-3004. doi: 10.1099/ijs.0.059766-0. Epub 2014 Jun 6.
Strains YIM 77562(T) and YIM 77580, two novel Gram-staining-positive, filamentous bacterial isolates, were recovered from the Rehai geothermal field, Tengchong, Yunnan province, south-west China. Good growth was observed at 50-55 °C and pH 7.0. Aerial mycelium was absent on all media tested. Substrate mycelium was well-developed, long and moderately flexuous, and formed abundant, single, warty, ornamented endospores. Phylogenetic analysis of the 16S rRNA gene sequences of the two strains indicated that they belong to the family Thermoactinomycetaceae. Similarity levels between the 16S rRNA gene sequences of the two strains and those of type strains of members of the Thermoactinomycetaceae were 88.33-93.24 %; the highest sequence similarity was with Hazenella coriacea DSM 45707(T). In both strains, the predominant menaquinone was MK-7, the diagnostic diamino acid was meso-diaminopimelic acid and the major cellular fatty acids were iso-C14 : 0, iso-C15 : 0 and iso-C16 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, unidentified polar lipids and unidentified phospholipids. The genomic DNA G+C contents of strains YIM 77562(T) and YIM 77580 were 45.5 and 44.2 mol%, respectively. DNA-DNA relatedness data suggest that the two isolates represent a single species. Based on phylogenetic analyses and physiological and biochemical characteristics, it is proposed that the two strains represent a single novel species in a new genus, Geothermomicrobium terrae gen. nov., sp. nov. The type strain of Geothermomicrobium terrae is YIM 77562(T) ( = CCTCC AA 2011022(T) = JCM 18057(T)).
两株新型革兰氏阳性、丝状细菌分离株 YIM 77562(T)和 YIM 77580 是从中国西南云南省腾冲热海地区分离得到的。它们在 50-55°C 和 pH 值为 7.0 的条件下生长良好。在所有测试的培养基上都没有气生菌丝。基内菌丝发育良好，长而适度弯曲，形成大量单个、疣状、装饰性的内生孢子。这两株菌的 16S rRNA 基因序列的系统发育分析表明，它们属于高温放线菌科。这两株菌的 16S rRNA 基因序列与高温放线菌科成员的模式菌株的相似度为 88.33-93.24%；与 Hazenella coriacea DSM 45707(T)的相似度最高。在这两株菌中，主要的类异戊二烯醌是 MK-7，主要的二氨基庚二酸是 meso-二氨基庚二酸，主要的细胞脂肪酸是 iso-C14:0、iso-C15:0 和 iso-C16:0。主要的极性脂是双磷脂酰甘油、磷脂酰甲乙醇胺、未鉴定的极性脂和未鉴定的磷脂。菌株 YIM 77562(T)和 YIM 77580 的基因组 DNA G+C 含量分别为 45.5 和 44.2mol%。DNA-DNA 同源性数据表明，这两个分离株代表一个单一的物种。基于系统发育分析和生理生化特征，建议这两个分离株代表一个新属 Geothermomicrobium terrae 属的一个新种，Geothermomicrobium terrae 种。该种的模式株是 YIM 77562(T)（ = CCTCC AA 2011022(T) = JCM 18057(T)）。
