Rhizobium quercicola sp. nov.

Cells are Gram-negative, non-motile, catalase-positive, oxidase-positive, non-nitrogen-fixing, rod-shaped and aerobic bacteria. After 3 days of incubation at 28 °C on YMA medium, colonies are milk-white, circular, middle convex, and smooth. The growth temperature ranges from 4 to 37 °C (optimum 28 °C), pH 4.0–9.0 (optimum pH 7.0) and tolerates 4% (w/v) NaCl concentration (optimum under 2% NaCl). The production of hydrogen sulphide (H2S), and reduction of nitrate and nitrite are negative. Lack of nitrogen-fixation on N-free plates, absence of nif genes in the draft genome sequence, and by annotation results. In the API 20E kit, positive for 2-nitrophenyl-ßDgalactopyranoside, sodium pyruvate and L-arabinose. In the API 20NE kit, positive for esculin ferric citrate, 4-nitrophenyl-βDgalactopyranoside, D-mannose, D-mannitol, D-maltose and malic acid. In the API ZYM kit, positive for alkaline phosphatase, esterase (C4), leucine arylamidase, cystine arylamidase, valine arylamidase, trypsin, α-chymotrypsin, acid phosphatase, α-glucosidase, β-galactosidase, N-acetyl-β-glucosaminidase and β-glucosidase, and weakly positive for esterase lipase (C8), lipase (C14), naphthol-AS-BI-phosphohydrolase, α-galactosidase and α-mannosidase. The following carbon sources are utilized: dextrin, D-maltose, D-trehalose, D-cellobiose, sucrose, α-D-lactose, α-D-glucose, D-mannose, D-fructose, D-galactose, D-sorbitol, D-mannitol, D-arabitol, myo-inositol, L-glutamic acid, pectin, L-galactonic acid lactone, α-keto-glutaric acid, L-malic acid, tween 40, acetoacetic acid, acetic acid and malic acid as sole carbon sources. The major fatty acids are C16:0, C18:1 ω7c and/or C18:1 ω6c and C18:1 ω7c 11–methyl. The only respiratory quinone is Q-10. The polar lipids are diphosphatidyl glycerol (DPG), phosphatidyl glycerol (PG), phosphatidylethanolamine (PE), phosphatidylmonomethylethanolamine (PME), phosphatidylcholine (PC), two unidentified phospholipid (PL) and nine unidentified lipids (L). The G + C content of the genomic DNA is 64.47 mol %.