A novel bacterial strain, designated LCJ02T, was isolated on R2A agar from donkey (Equus asinus) milk powder and subjected to a taxonomic study using a polyphasic approach. Strain LCJ02T showed a Gram-negative reaction, was non-motile, non-spore-forming and possessed rod-shaped cells and yellow-pigmented colonies. Phylogenetic analysis based on 16S rRNA gene sequences showed that the novel isolates formed a cluster with several uncultured bacterial clones and with cultured members of the genera Hydrotalea, Sediminibacterium, and Lacibacter

(family Chitinophagaceae, phylum Bacteroidetes). The gene sequence similarities with respect to the type strains of recognized species from the above genera and other phylogenetic neighbors ranged from 89.3 to 92.9 %. The G+C content of the genomic DNA was 49.2 mol%, the only isoprenoid quinone was MK-7 and the major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15: 1 G and summed feature 3 (C16 : 1v7c and/or iso-C15 : 0 2-OH). The major polar lipids of strain LCJ02T were phosphatidylethanolamine, two unidentified amino phospholipids, one unidentified amino lipid and five unidentified lipids. The results of physiological and biochemical tests allowed phenotypic differentiation of strain LCJ02T from its closest phylogenetic neighbors.

On the basis of the evidence of this polyphasic study, isolate LCJ02T represents a novel genus and species in the family Chitinophagaceae for which the name Asinibacterium lactis gen. nov., sp. nov. is proposed. The type strain is LCJ02T (5KCCM 90108T5JCM 18484T)