Hubeiibacter gen. nov., a new genus of Moraxellaceae: identification of Hubeiibacter jixunmingi sp. nov. isolated from blowhole swab samples of Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis)

Three strains designated c1-l78 T , c2-A9 and c3-l95 were isolated from blowhole swab samples of Yangtze finless porpoise ( Neophocaena asiaeorientalis asiaeorientalis ) in Hubei Province, China. The strains are Gram-stain-negative, oxidase-positive, catalase-positive, obligately aerobic, non-motile, non-haemolytic, proteolytic and short-rod-shaped bacteria. Based on 16S rRNA gene sequence analysis, strain c1-l78 T was assigned to the family Moraxellaceae (order Pseudomonadales ), with the genus Acinetobacter being its closest relative (93.96 % similarity). Average nucleotide identity and digital DNA-DNA hybridization values between c1-l78 T and type strains of all validly published species of the genus Acinetobacter were very low, ranging from 71.2 to 73.2 % and 20.9 to 26.6 %, respectively. The average amino acid identity was 65.0-69.9 % with orthologous fraction (55.3-67.5 %), and the percentage of conserved proteins was 39.0-55.4 %. Phylogenomic analysis further confirmed a distinct lineage, supported by a high relative evolutionary divergence value of ~0.94. The DNA G+C content of strain c1-l78 T is 39.1 mol %. The major cellular fatty acids were 9-octadecenoic acid (C 18 : 1 ω 9 c ), summed feature 3 (C 16 : 1 ω 7 c /C 16 : 1 ω 6 c ) and hexadecanoic acid (C 16 : 0 ). The sole respiratory quinone was ubiquinone-8, and the major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and an unknown aminophosphoglycolipid. Based on the polyphasic analysis, we propose that the three strains represent a novel genus and species, for which the name Hubeiibacter gen. nov., type species Hubeiibacter jixunmingi gen. nov., sp. nov. is proposed. The type strain is c1-l78 T (=GDMCC 1.4970 T =JCM 37696 T ).