Paenibacillus crassostreae sp. nov., isolated from the Pacific oyster Crassostrea gigas.

A Gram-stain-positive, endospore-forming, rod-shaped, aerobic bacterium, designated LPB0068, was isolated from a Pacific oyster (Crassostrea gigas) in Korea. This isolate was found to share the highest 16S rRNA gene sequence similarity with Paenibacillus macquariensis subsp. macquariensis DSM 2 (98.1 %) and Paenibacillus macquariensis subsp. defensor JCM 14954 (98.0 %). To establish the genomic relatedness of this isolate to its phylogenetic neighbours, its genome sequence and those of Paenibacillus antarcticus CECT 5836, P. macquariensis subsp. macquariensis DSM 2, P. macquariensis subsp. defensor JCM 14954, and Paenibacillus glacialis DSM 22343 were determined. The low average nucleotide identity and digital DNA-DNA hybridization values exhibited by LPB0068 in relation to the other strains in this analysis revealed that it is distinct from other Paenibacillus species. The genome of strain LPB0068 consists of one chromosome and three circular plasmids, and had a DNA G+C content of 40.0 mol%. The major respiratory quinone was menaquinone-7 and the diagnostic diamino acid in the cell-wall peptidoglycan was meso-diaminopimelic acid. The major polar lipids consisted of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, one unidentified phospholipid, one unidentified glycolipid, and two unidentified polar lipids. The major cellular fatty acids were anteiso-C15 : 0, C14 : 0, and C16 : 0. Based on genomic, phylogenetic, and phenotypic characteristics, this strain was clearly distinguished from other Paenibacillus species with validly published names and should therefore be classified as a novel species of the genus. The name Paenibacillus crassostreae sp. nov. is proposed, the type strain of which is LPB0068 (=KACC 18694=JCM 31183).