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 (<i>Neophocaena asiaeorientalis asiaeorientalis</i>) 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 <i>Moraxellaceae</i> (order <i>Pseudomonadales</i>), with the genus <i>Acinetobacter</i> 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 <i>Acinetobacter</i> 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} <i> ω</i>9<i>c</i>), summed feature 3 (C_{16 : 1} <i> ω</i>7<i>c</i>/C_{16 : 1} <i> ω</i>6<i>c</i>) 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 <i>Hubeiibacter</i> gen. nov., type species <i>Hubeiibacter jixunmingi</i> gen. nov., sp. nov. is proposed. The type strain is c1-l78^T (=GDMCC 1.4970^T=JCM 37696^T).