The bacterial strain SJT, along with 15 other mesophilic, neutrophilic and facultatively sulfur-oxidizing chemolithotrophic isolates, was isolated by enrichment on reduced sulfur compounds as the sole energy and electron source from soils immediately adjacent to the roots of , a slender leguminous herb of the Lower Gangetic plains of India. Strain SJT was able to oxidize thiosulfate and elemental sulfur for chemolithoautotrophic growth. 16S rRNA and gene sequence-based phylogenetic analyses showed that the Gram-negative rod-shaped bacterium belonged to the genus and was most closely related to , , and . Unequivocally low 16S rRNA (<97 %) and (⩽88 %) gene sequence similarities to all existing species of the most closely related genera, a unique fatty acid profile, a distinct G+C content (59·6 mol%) and phenotypic characteristics all suggested that strain SJT represents a novel species. DNA–DNA hybridization and SDS-PAGE analysis of whole-cell proteins also confirmed the taxonomic uniqueness of SJT. It is therefore proposed that isolate SJT (=LMG 22697=MTCC 7001) be classified as the type strain of a novel species, sp. nov.


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Phenogram of sp. nov. SJT and related strains deduced by comparing their available phenotypic characteristics. [PDF](40 KB)


Coomassie blue-stained SDS-PAGE gel of whole-cell-protein preparations from sp. nov. SJT (duplicate samples in lanes 1 and 2) in comparison with its phylogenetic relatives KCT001 (lane 3), LMG 17826 t2 (4), LMG 18932 (5), LMG 19008 (6) and LMG 11892 (7).


Fatty acid profile of sp. nov. SJT in comparison with related taxa. [PDF](26 KB)

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