Meiothermus terrae sp. nov., isolated from a geothermally heated soil sample

Abstract

A Gram-negative, aerobic bacterium, designated strain YIM 77755(T), was isolated from a geothermally heated soil sample collected at Rehai National Park, Tengchong, Yunnan province, south-west China. Cells of the strain were rod-shaped and colonies were yellow and circular. Growth occurred in 0-1 % (w/v) NaCl, at pH 6.0-8.0 (optimum, pH 7.0) and at 35-55 °C (optimum, 50 °C). The predominant menaquinone was MK-8 and the DNA G+C content was 68.9 mol%. Major fatty acids (>10 %) were anteiso-C15 : 0 and iso-C15 : 0. The polar lipids consisted of an uncharacterized phospholipid and four glycolipids. Based on 16S rRNA gene sequence analysis, strain YIM 77755(T) formed a cluster with Meiothermus chliarophilus ALT-8(T) and showed the highest 16S rRNA gene sequence similarity to M. chliarophilus ALT-8(T) (98.23 %). DNA-DNA relatedness between YIM 77755(T) and M. chliarophilus DSM 9957(T) was 54.9±4.1 %. On the basis of the morphological and chemotaxonomic characteristics as well as genotypic data, it is proposed that strain YIM 77755(T) represents a novel species of the genus Meiothermus, named Meiothermus terrae sp. nov. The type strain is YIM 77755(T) ( = DSM 26712(T) = CCTCC AB 2012942(T)).