Bacillus nitroreducens sp nov., a humus-reducing bacterium isolated from a compost

A Gram-staining-positive, facultative anaerobic, motile and rod-shaped bacterium, designated GSS08(T), was isolated from a windrow compost pile and characterized by means of a polyphasic approach. Growth occurred with 0-4 % (w/v) NaCl (optimum 1 %), at pH 6.5-9.5 (optimum pH 7.5) and at 20-45 degrees C (optimum 37 degrees C). Anaerobic growth occurred with anthraquinone-2,6-disulphonate, fumarate and NO3- as electron acceptor. The main respiratory quinone was MK-7. The predominant polar lipids were diphosphatidylglycerol and phosphatidylethanolamine. The major fatty acids (>5 %) were iso-C-15:0 (43.1 %), anteiso-C-15:0 (27.4 %) and iso-C-16:0 (8.3 %). The DNA G + C content was 39.6 mol%. The phylogenetic analysis based on 16S rRNA gene sequences revealed that strain GSS08(T) formed a phyletic lineage with the type strain of Bacillus humi DSM 16318(T) with a high sequence similarity of 97.5 %, but it displayed low sequence similarity with other valid species in the genus Bacillus (<96.0 %). The DNA-DNA relatedness between strains GSS08(T) and B. humi DSM 16318(T) was 50.8 %. The results of phenotypic, chemotaxonomic and genotypic analyses clearly indicated that strain GSS08(T) represents a novel species, for which the name Bacillus nitroreducens sp. nov. is proposed. The type strain is GSS08(T) (=KCTC 33699(T) = MCCC 1K01091(T)).