Thermus caldilimi sp. nov., a thermophilic bacterium isolated from a geothermal area
- 62 Downloads
A Gram-stain negative, aerobic bacterium, designated strain YIM 78456T, was isolated from a hot spring sediment, Ngamring county, Tibet, south-west China. The taxonomic position of the isolate was investigated by a polyphasic approach. The novel isolate was found to be aerobic and rod-shaped. Colonies were observed to be pale yellow and circular. The strain was found to grow at pH 7.0–8.0 (optimum, pH 7.0), 45–65 °C (optimum, 55 °C) and in the presence of up to 1.5% NaCl. Comparison of the 16S rRNA gene sequence of strain YIM 78456T and other members of the genus Thermus showed sequence similarities ranging from 90.3 to 97.3%, with strain YIM 78456T showing close sequence similarity to Thermus caliditerrae YIM 77925T (97.3%). The phylogenetic trees based on 16S rRNA gene sequences showed that strain YIM 78456T forms a distinct clade with T. caliditerrae YIM 77925T. The predominant menaquinone was identified as MK-8 and the DNA G+C content was determined to be 65.1 mol%. The major cellular fatty acids (> 10%) were identified as iso-C15:0, anteiso-C15:0 and iso-C17:0. The polar lipids were found to consist of an aminophospholipid, a phospholipid and glycolipids. On the basis of the morphological and chemotaxonomic characteristics, as well as genotypic data, it is proposed that strain YIM 78456T represents a novel species of the genus Thermus, for which the name Thermus caldilimi sp. nov. is proposed. The type strain is YIM 78456T (= KCTC 52948T = NBRC 113036T).
KeywordsThermus caldilimi sp. nov. Hot spring Tibet Polyphasic approach
This research was supported by China Ministry of Science and Technology (No. 2015FY110100), Natural Science Foundation of China (No. 31600103) and Natural Science Foundation of Guangdong Province, China (No. 2016A030312003).
WJL conceived the study. MML, BZF, XTZ, YRY, EMZ, YPD, LL performed research. MML, WDX and XTZ analyzed data. MML, WDX and WJL wrote the paper. All authors approved the manuscript.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no direct or indirect conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
- Bjornsdottir SH, Petursdottir SK, Hreggvidsson GO, Skirnisdottir S, Hjorleifsdottir S, Arnfinnsson J, Kristjansson JK (2009) Thermus islandicus sp. nov., a mixotrophic sulfuroxidizing bacterium isolated from the Torfajokull geothermal area. Int J Syst Evol Microbiol 59:2962–2966CrossRefGoogle Scholar
- Buck JD (1982) Nonstaining (KOH) method for determination of gram reactions of marine bacteria. Appl Environ Microb 44:992–993Google Scholar
- Kimura M (1985) The neutral theory of molecular evolution. Cambridge University Press, CambridgeGoogle Scholar
- MacFaddin JF (1976) Biochemical tests for identification of medical bacteria, vol 238. Williams & Wilkins Co., BaltimoreGoogle Scholar
- Minnikin DE, O’Donnell A, Goodfellow M, Alderson G, Athalye M et al (1984) An integrated procedure for the extraction of bacterial isoprenoid quinones and polar lipids. J Appl Bacteriol 2:233–241Google Scholar
- Nobre MF, Trüper HG, da Costa MS et al (1999) Transfer of Thermus ruber (Loginova et al. 1984), Thermus silvanus (Tenreiro et al. 1995), and Thermus chliarophilus (Tenreiro et al. 1995) to Meiothermus gen. nov. as Meiothermus ruber comb, nov., Meiothermus silvanus comb. nov., and Meiothermus chliarophilus comb. nov., respectively, and emendation of the genus Thermus. Int J Syst Evol Microbiol 49:1951Google Scholar
- Saitou N, Nei M (1987) The neighbor-joining method: a new method for reconstructing phylogenetic trees. Mol Biol Evol 4:406–425Google Scholar
- Sasser M (1990) Identification of bacteria by gas chromatography of cellular fatty acids, MIDI Technical note 101. Microbial ID Inc., NewarkGoogle Scholar
- Smibert R, Krieg NR (1994) Phenotypic characterization. In: Gerhardt P, Murray TGE, Wood WA, Krieg NR (eds) Methods for general and molecular bacteriology. American Society for Microbiology, Washington, pp 607–654Google Scholar
- Zhou EM, Xian WD, Mefferd CC, Thomas SC, Adegboruwa AL, Williams N, Murugapiran SK, Dodsworth JA, Ganji R, Li MM, Ding YP, Liu L, Woyke T, Li WJ, Hedlund BP (2018) Thermus sediminis sp nov., a thiosulfate-oxidizing and arsenate-reducing organism isolated from Little Hot Creek in the Long Valley Caldera, California. Extremophiles 22:983–991CrossRefGoogle Scholar