Hansschlegelia quercus sp. nov., a novel methylotrophic bacterium isolated from oak buds

Novel aerobic, restricted facultatively methylotrophic bacteria were isolated from buds of English oak (Quercus robur L.; strain Dub^T) and northern red oak (Quercus rubra L.; strain KrD). The isolates were Gram-negative, asporogenous, motile short rods that multiplied by binary fisson. They utilized methanol, methylamine and a few polycarbon compounds as carbon and energy sources. Optimal growth occurred at 25 °C and pH 7.5. The dominant phospholipids were phosphatidylethanolamine, phosphatidylcholine, diphosphatidylglycerol and phoshatidylglycerol. The major cellular fatty acids of cells were C_18 : 1 ω7c, 11-methyl C_18 : 1 ω7c and C_16 : 0. The major ubiquinone was Q-10. Analysis of 16S rRNA gene sequences showed that the strains were closely related to the members of the genus Hansschlegelia: Hansschlegelia zhihuaiae S113^T(97.5-98.0 %), Hansschlegelia plantiphila S1^T (97.4-97.6 %) and Hansschlegelia beijingensis PG04^T(97.0-97.2 %). The 16S rRNA gene sequence similarity between strains Dub^T and KrD was 99.7 %, and the DNA-DNA hybridization (DDH) result between the strains was 85 %. The ANI and the DDH values between strain Dub^T and H. zhihuaiae S113^T were 80.1 and 21.5  %, respectively. Genome sequencing of the strain Dub^T revealed a genome size of 3.57 Mbp and a G+C content of 67.0 mol%. Based on the results of the phenotypic, chemotaxonomic and genotypic analyses, it is proposed that the isolates be assigned to the genus Hansschlegelia as Hansschlegelia quercus sp. nov. with the type strain Dub^T (=VKM B-3284^T=CCUG 73648^T=JCM 33463^T).