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A gram-negative, motile, straight to curved rod shaped, pink pigmented bacterium was isolated from a soil sample collected from the rhizosphere of an Indian medicinal plant, Nerium indicum (Chuvanna arali) and subjected to a detailed polyphasic taxonomic study. The strain, designated as IMTB-1969(T), matched with most of the phenotypic and chemotaxonomic properties of the genus Pontibacter and represents a novel species. The major fatty acids of the strain were monounsaturated iso/anteiso branched C17 fatty acids (45.1%) and iso-C15:0 (16.5%). MK-7 was the predominant isoprenoid quinone. According to 16S rRNA gene sequence analysis, strain IMTB-1969(T) was indicated to belonged to the phylum Bacteroidetes and further phylogenetic analysis revealed that the strain IMTB-1969(T) belongs to the family Cytophagaceae and genus Pontibacter. The highest 16S rRNA gene sequence similarity was with Pontibacter korlensis CCTCC AB 206081(T) (97.2%) and lower sequence similarity was observed with other species in the genus Pontibacter (95.9-94.0%). DNA-DNA relatedness study of the strain IMTB-1969(T) confirmed that it represents a novel species. The G+C content of the genomic DNA was 52.2 (±0.5) mol%. The results of physiological and biochemical tests allowed the genotypic and phenotypic distinction of strain IMTB-1969(T) from its closest phylogenetic relatives. The strain IMTB-1969(T) should be classified as novel species of the genus Pontibacter, for which the name Pontibacter rhizosphera sp. nov. is proposed. The type strain is IMTB-1969(T) (=MTCC 10673(T) = DSM 24399(T)).

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.

A straw-yellow pigmented bacterium, strain IITR-21(T) was isolated from a pesticide contaminated site and characterized by using a polyphasic taxonomic approach. The organism had morphological and chemotaxonomic properties consistent with its classification in the genus Nitratireductor. Phylogenetic analysis of the 16S rRNA gene sequence showed that the strain IITR-21(T) belongs to the genus Nitratireductor and was moderately related to Nitratireductor indicus C115(T) (97.7%) and Nitratireductor pacificus pht-3B(T) (97.4%), whereas sequence similarity value with the other species including the type species of the genus Nitratireductor, Nitratireductor aquibiodomus showed less than 97.0% similarity. However, the DNA-DNA relatedness values between strain IITR-21(T) and the moderately related taxa N. indicus (59.1%) and N. pacificus (40.4%) were well below the 70% threshold value recommended for the delineation of bacterial species. The G+C content of the DNA was 62.4 mol%. Based on physiological, biochemical tests and genotypic differences between the strain IITR-21(T) and the other two validly published species of the genus Nitratireductor, it is proposed that the strain be classified as a new species of Nitratireductor as Nitratireductor lucknowense sp. nov. The type strain is IITR-21(T) (=MTCC 8354(T )= DSM 24322(T)).