Proposal of Viridibacillus gen. nov. and reclassification of Bacillus arvi, Bacillus arenosi and Bacillus neidei as Viridibacillus arvi gen. nov., comb. nov., Viridibacillus arenosi comb. nov. and Viridibacillus neidei comb. nov.

Abstract

A polyphasic study was undertaken to clarify the taxonomic position of endospore-forming strains 433-D9, 433-E17 and 121-X1. BOX-PCR-generated fingerprints indicated that they may be members of a single species. 16S rRNA gene sequence similarity demonstrated that a representative of this group, 433-D9, is affiliated closely with Bacillus arvi DSM 16317T (100 %), Bacillus arenosi DSM 16319T (99.8 %) and Bacillus neidei NRRL BD-87T (97.1 %). Sequence similarities revealed Bacillus pycnus NRRL NRS-1691T and several Kurthia species as the next nearest relatives. DNA–DNA hybridization results showed that strain 433-D9 is a member of B. arvi. Detection of l-Lys–d-Asp-based peptidoglycan in strain 433-D9, B. arvi DSM 16317T and B. arenosi DSM 16319T was in agreement with their close relationship, but differentiated these strains from B. neidei NRRL BD-87T and B. pycnus NRRL NRS-1691T, for which l-Lys–d-Glu was reported. A similar quinone system was detected in strains 433-D9, 433-E17, 121-X1, B. arvi DSM 16317T, B. arenosi DSM 16319T and B. neidei NRRL BD-87T. This system, unusual for bacilli, consisted of the major compound menaquinone MK-8 (69–80 %) and moderate amounts of MK-7 (19–30 %). This observation was in contrast to the predominance of MK-7 of the closest relative B. pycnus NRRL NRS-1691T, as also reported for representatives of the closely related non-endospore-forming genus Kurthia. Strains 433-D9, B. arvi DSM 16317T and B. arenosi DSM 16319T exhibited homogeneous and discriminative polar lipid profiles and fatty acid profiles consisting of major acids i-C15 : 0 and ai-C15 : 0 and moderate amounts of i-C17 : 1 ω10c and i-C17 : 1 I/ai-C17 : 1 B that discriminated them from closely related strains such as B. neidei NRRL BD-87T. On the basis of clear-cut discriminative chemotaxonomic markers, we propose strains 433-D9, 433-E17 and 121-X1, B. arvi DSM 16317T, B. arenosi DSM 16319T and B. neidei NRRL BD-87T to be reclassified within a separate genus. For this new taxon, we propose the name Viridibacillus gen. nov., and we propose the reclassification of Bacillus arvi, Bacillus arenosi and Bacillus neidei as Viridibacillus arvi gen. nov., comb. nov. (the type species of Viridibacillus, with the type strain DSM 16317T =LMG 22165T), Viridibacillus arenosi comb. nov. (type strain DSM 16319T =LMG 22166T) and Viridibacillus neidei comb. nov. (type strain NRRL BD-87T =DSM 15031T =JCM 11077T).

Bacillus oceanisediminis sp. nov., isolated from marine sediment

“…The polar lipid profile of B. subtilis has been shown to be characteristic of the genus Bacillus and should form part of the genus description (Kämpfer et al, 2006). The polar lipid profile of B. subtilis comprises diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unknown aminophospholipid and b-gentiobiosyldiacylglycerol (Kämpfer et al, 2006;Albert et al, 2007), while the polar lipids of F. pallidus comprise diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two aminophosphoglycolipids, five unknown phospholipids, two phosphoglycolipids and one glycolipid (Zhou et al, 2009). The polar lipid profile of strain H2 T was similar to those for the genus Bacillus.…”

“…These isoand anteiso-branched fatty acids of the 14-17-carbon series are typical of those found in the cell membranes of members of the genus Bacillus (Kämpfer, 1994; Albert et al, 2005). Thus, these chemotaxonomic features of strain H2 T were typical of those for the genus Bacillus (Priest et al, 1988;Heyrman et al, 2004; Albert et al, 2005Albert et al, , 2007Wieser et al, 2005; Lim et al, 2006a, b;Xue et al, 2008). In addition, the DNA G+C content of strain H2 T was 44.8 mol%, which is within the range for the genus Bacillus (Nielsen et al, 1995;Priest et al, 1988).…”

“…Some species have been reclassified in novel genera or transferred to other genera (Ash et al, 1993;Stackebrandt & Liesack, 1993;Shida et al, 1996;Wainø et al, 1999;Nazina et al, 2001;Yoon et al, 2001;Albert et al, 2007;Zhou et al, 2009). Many of these reclassifications are well supported by relatively conserved phenotypic traits such as the quinone system, peptidoglycan composition and polar lipid and cellular fatty acid profiles (Albert et al, 2007). Falsibacillus is a newly described genus, which currently comprises a single species, Falsibacillus pallidus comb.…”

Re-examination of the taxonomic position of Bacillus silvestris Rheims et al. 1999 and proposal to transfer it to Solibacillus gen. nov. as Solibacillus silvestris comb. nov.

“…Except for B. silvestris, data for peptidoglycan composition, polar lipids and often fatty acids are lacking for those Bacillus species that together with B. silvestris belong to the same clade (B. odysseyi, B. massiliensis, B. pycnus). Many investigators have suggested that species placed within the genus Bacillus in Bacillus rRNA group 2 do not belong to it and should be reclassified either into novel genera or into pre-existing genera within the group (Farrow et al, 1994;Yoon et al, 2001;Ahmed et al, 2007;Albert et al, 2007). As for the taxonomic position of B. odysseyi, B. massiliensis and B. pycnus, all three species seem to be phylogenetically distantly related to B. silvestris (Supplementary Table S1 and Fig.…”

“…Recently Ahmed et al (2007) proposed the transfer of two additional rRNA group 2 Bacillus species, i.e. B. fusiformis and B. sphaericus, into a newly created genus Lysinibacillus and Albert et al (2007) proposed a new genus Viridibacillus to include the species Bacillus arvi, Bacillus arenosi and Bacillus neidei. Five of the six species originally placed in Bacillus rRNA group 2 were excluded from this genus and reclassified as members of existing or new genera.…”