Genome Sequences of the Biotechnologically Important Bacillus megaterium Strains QM B1551 and DSM319

Institute for Genomic Sciences and Department of Microbiology and Immunology, University of Maryland, School of Medicine, Baltimore, MD 21201, USA.
Journal of bacteriology (Impact Factor: 2.81). 06/2011; 193(16):4199-213. DOI: 10.1128/JB.00449-11
Source: PubMed


Bacillus megaterium is deep-rooted in the Bacillus phylogeny, making it an evolutionarily key species and of particular importance in understanding genome evolution, dynamics,
and plasticity in the bacilli. B. megaterium is a commercially available, nonpathogenic host for the biotechnological production of several substances, including vitamin
B12, penicillin acylase, and amylases. Here, we report the analysis of the first complete genome sequences of two important B. megaterium strains, the plasmidless strain DSM319 and QM B1551, which harbors seven indigenous plasmids. The 5.1-Mbp chromosome carries
approximately 5,300 genes, while QM B1551 plasmids represent a combined 417 kb and 523 genes, one of the largest plasmid arrays
sequenced in a single bacterial strain. We have documented extensive gene transfer between the plasmids and the chromosome.
Each strain carries roughly 300 strain-specific chromosomal genes that account for differences in their experimentally confirmed
phenotypes. B. megaterium is able to synthesize vitamin B12 through an oxygen-independent adenosylcobalamin pathway, which together with other key energetic and metabolic pathways has
now been fully reconstructed. Other novel genes include a second ftsZ gene, which may be responsible for the large cell size of members of this species, as well as genes for gas vesicles, a second
β-galactosidase gene, and most but not all of the genes needed for genetic competence. Comprehensive analyses of the global
Bacillus gene pool showed that only an asymmetric region around the origin of replication was syntenic across the genus. This appears
to be a characteristic feature of the Bacillus spp. genome architecture and may be key to their sporulating lifestyle.

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    • "Comparing USB2103 16S rDNA sequence with sequences available in the NCBI Databases revealed high similarity (99 %) with strains DSM 319 and QMB 1551 (Eppinger et al. 2011) of Bacillus megaterium. B a c t e r i a l 1 6 S r D N A p a r t i a l s e q u e n c e s o f P. brassicacearum USB2101, USB2102 and USB2104, "
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