Abstract
Three new bacterial strains, WHY3(T), WH131(T), and WH158(T), were isolated and described from the hemolymph of the Pacific oyster Crassostrea gigas utilizing polyphasic taxonomic techniques. The 16S rRNA gene sequence analysis revealed that strain WHY3(T) was a member of the genus Winogradskyella, whereas strains WHI31(T) and WH158(T) were members of the genus Erythrobacter. According to the polygenomic study the three strains formed individual lineages with strong bootstrap support. The comparison of dDDH-and ANI values, percentage of conserved proteins (POCP), and average amino acid identity (AAl) between the three strains and their relatives established that the three strains represented two separate genera. Menaquinone-6 was reported as the major respiratory quinone in strain WHY3(T) and Ubiquinone-10 for strains WH131(T) and WH158(T), respectively. The major cellular fatty acids for strain WHY3(T) were C(15:0), anteiso-C(15:1) ω7c, iso-C(15:0), C(16:1)ω7c. The major cellular fatty acids for strains WH131(T) and WH158(T) were C(14:0)2-OH and t(18:1)ω12 for WH131(T) and C(17:0,) and C(18:1)ω7c for strain WH158(T). Positive Sudan Black B staining Indicated the presence of polyhydroxyalkanoic acid granules for strains WH131(T) and WH158(T) but not for strain WHY3(T). The DNA G + C contents of strains WHY3(T), WH131(T) and WH158(T) were 34.4, 59.7 and 56.6%, respectively. Gene clusters predicted some important genes involved in the bioremediation process. Due to the accomplishment of polyphasic taxonomy, we propose three novel species Winogradskyella luteola sp.nov. (type strain WHY3(T) = DSM 111804(T) = NCCB 100833(T)), Erythrobacter ani sp.nov. (WH131(T) = DSM 112099(T) = NCCB 100824(T)) and Erythrobacter crassostrea sp.nov. (WH158(T) = DSM 112102(T) = NCCB 100877(T)).