A Gram-positive bacterium, designated strain CBMB205 T , was isolated from the rhizosphere soil of traditionally cultivated, field-grown rice. Cells were strictly aerobic, motile, rod-shaped and formed endospores. The best growth was achieved at 30 6C and pH 7.0 in ammonium mineral salts (AMS) medium containing 600 mM methanol. A comparative 16S rRNA gene sequencebased phylogenetic analysis placed strain CBMB205 T in a clade with the species Bacillus amyloliquefaciens, Bacillus vallismortis, Bacillus subtilis, Bacillus atrophaeus, Bacillus mojavensis and Bacillus licheniformis and revealed pairwise similarities ranging from 98.2 to 99.2 %. DNA-DNA hybridization experiments revealed a low level (,36 %) of DNA-DNA relatedness between strain CBMB205 T and its closest relatives. The major components of the fatty acid profile were C 15 : 0 anteiso, C 15 : 0 iso, C 16 : 0 iso and C 17 : 0 anteiso. The diagnostic diamino acid of the cell wall was meso-diaminopimelic acid. The G+C content of the genomic DNA was 45.0 mol%. The lipids present in strain CBMB205 T were diphosphatidylglycerol, phosphatidylglycerol, a minor amount of phosphatidylcholine and two unknown phospholipids. The predominant respiratory quinone was MK-7. Studies of DNA-DNA relatedness, morphological, physiological and chemotaxonomic analyses and phylogenetic data based on 16S rRNA gene sequencing enabled strain CBMB205 T to be described as representing a novel species of the genus Bacillus, for which the name Bacillus methylotrophicus sp. nov. is proposed. The type strain is CBMB205 T (5KACC 13105 T 5NCCB 100236 T ).Methylotrophy has been recognized as a property of specialized bacteria that are capable of growth on C1-compounds and members of numerous genera and species have been found to possess this ability (Whittenbury et al., 1970;Arfman et al., 1992;Kalyuzhnaya et al., 2006;Lidstrom, 2006). It has been found that the occurrence of methylotrophy in prokaryotes does not correlate with traditional bacterial classification (Brautaset et al., 2004), as facultative methylotrophy has been shown to be a property of diverse typically heterotrophic genera (Boden et al., 2008). One of the earliest methylotrophic organisms to be isolated was the Gram-positive bacterium, 'Bacillus methylicus' (later renamed as 'Bacterium methylicum', but no longer available in culture). This aerobic, non-sporeforming, facultative methylotroph produced red pigment when grown on formate or methanol and also grew on formaldehyde (Loew, 1892;Migula, 1900;Bergey et al., 1939). Numerous specialized methylotrophs have since been described, including a great diversity of methanotrophs, some of which are obligate methane users, many that also use methanol and a few that are capable of growth on multicarbon compounds (Whittenbury et al., 1970;Dedysh et al., 2005). At the time of writing, the genus Bacillus, in the phylum Firmicutes, consisted of 225 species with validly published names (http://www.bacterio.cict.fr/ b/bacillus.html) with Bacillus subtilis as the type species (Cohn, 187...