Exiguobacterium himgiriensis sp. nov. a novel member of the genus Exiguobacterium, isolated from the Indian Himalayas.

摘要

The taxonomic position of an orange coloured bacterium, strain K22-26(T) isolated from a soil sample was studied using a polyphasic approach. The organism had phenotypic and chemotaxonomic properties consistent with its allocation into the genus Exiguobacterium. Phylogenetic analysis of the 16S rRNA gene sequence showed that strain K22-26(T) belongs to the genus Exiguobacterium and was related to Exiguobacterium aurantiacum DSM 6208(T) (99.0?%) Exiguobacterium mexicanum DSM 16483(T) (98.6?%), Exiguobacterium aquaticum (98.6?%), Exiguobacterium aestuarii DSM 16306(T) (98.1?%), Exiguobacterium profundum DSM 17289(T) (98.1?%) and Exiguobacterium marinum DSM 16483(T) (97.9?%), whereas sequence similarity values with respect to other Exiguobacterium species with validly published names were between 92.5-94.0?%. The major polar lipids detected were phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. The major menaquinone was determined to be MK-7 (83?%) whereas MK-8 (11?%) and MK-6 (6?%) occur in smaller amounts. The peptidoglycan of the strain was found to contain L-lysine as the diagnostic diamino acid. The major fatty acids detected were iso C13:0 (11.2?%), anteiso C13:0 (15.4?%), iso C15:0 (13.2?%) and iso C17:0 (16.1?%). However, analysis of the DNA-DNA relatedness confirmed that strain K22-26(T) belongs to a novel species. The G?+?C content of the strain K22-26(T) was determined to be 50.1?mol?%. The novel strain was distinguished from closely related type species of the genus Exiguobacterium using DNA-DNA relatedness and phenotypic data. Based on these differences, the strain K22-26(T) should be classified as a novel species of the genus Exiguobacterium, for which the name Exiguobacterium himgiriensis sp. nov. strain K22-26(T) (=?MTCC 7628(T)?=?JCM 14260(T)) is proposed.