Strain CSC1952T phylogenetically formed a distinct group within the genus Neorhizobium. The chemotaxonomic profiles of strain CSC1952T were generally similar to N. petrolearium SL-1Tand R. deserti SPY-1T. However, some physiological and biochemical properties, such as polar lipids, enzyme activities, carbon sources, and acid production substrates, distinguished strain CSC1952T from N. petrolearium SL-1Tand R. deserti SPY-1T. Therefore, strain CSC1952T represents a novel species of the genus Neorhizobium, for which the name Neorhizobium ytuae sp. nov. is proposed.
Description of Neorhizobium ytuae sp. nov.
Neorhizobium ytuae (y.tu’ae. N.L. gen. n. ytuae, named arbitrarily formed from YTU, the acronym for Yantai University, in which the microbiologists who first isolated the organism worked).
Cells of strain CSC1952T are Gram-stain-negative, flagellated, rod-shaped with 0.5–0.9 µm in width and 1.5–2.3 µm in length. Colonies on 2216EA are circular, slightly convex, smooth, pale-yellow, and approximately 2–3 mm in diameter after incubation for 2 days at 28°C. Growth of strain CSC1952T occurred at 10–40°C (optimum, 30°C), pH 5.0–11.0 (optimum, 6.0–7.0) and with 0–5.0% (w/v) NaCl (optimum, 0–1.0%). Casein, gelatin, oxidase, starch and tween 60 and 80 are negative, but hydrogen peroxide, urea, tween 20 and 40 can be hydrolyzed. Activities of alkaline phosphatase, esterase (C4), leucine arylamidase, valine arylamidase, cystine arylamidase, acid phosphatase, α-glucosidase, β-glucosidase, trypsin, α-chymotrypsin, and naphthol-AS-BI-phosphohydrolase are present, activities of α-galactosidase, β-glucuronidase, N-acetyl-β-glucosaminidase, α-mannosidase, and α-fucosidase. Acid can be produced from l-arabinose, d-xylose, d-glucose, d-fructose, d-Mannose, l-rhamnose, sorbitol, esculin ferric citrate, d-fucose, d-lyxose, d-arabinose, d-gentiobiose, 2-keto-gluconate, d-galactose, d-ribose, l-fucose, and d-arabitol. Acid cannot be produced from erythritol, l-xylose, d-side-marigold alcohol, methyl-β-d-xylopyranoside, l-sorbose, inositol, methyl-α-d-mannopyranoside, methyl-α-d-glucopyranoside, amygdalin, arbulin, salicin, d-sucrose, d-melezitose, d-raffinose, starch, xylitol, d-turanose, l-arabitol, mannitol, glycogen, 5-keto-gluconate, d-tagatose, dulcitol, mannitol, N-acetyl-d-glucosamine, d-maltose, d-lactose, d-melibiose, d-trehalose, and gluconate. Urea, aesculin, p-nitrophenyl-β-d-galactopyranoside can be utilized as carbon and energy sources, whereas potassium nitrate, l-tryptophan, d-glucose, l-arginine, gelatin, potassium nitrate, l-tryptophan, d-glucose, l-arginine, d-glucose, l-arabinose, d-mannose, d-mannitol, N-acetylglucosamine, d-maltose, potassium gluconate, capric acid, adipic acid, malic acid, trisodium citrate, and phenylacetic acid are not. The G + C content of the genomic DNA of strain CSC1952T is 62.8%. The major fatty acids of strain CSC1952T contained C16:0, C19:0 cyclo ω 8c, summed feature 2 and 8. The polar lipids include phosphatidylglycerol (PG), phosphatidylethanolamine (PE), phosphatidylcholine (PC), unidentified aminolipid (AL), phosphatidylmethylethanolamine (PME), diphosphatidylglycerol (DPG), unidentified glycolipid (GL) and unidentified phospholipids (PL1-2).
The type strain, CSC1952T (= MCCC 1K08370T = LMG 33224T), which was isolated from a cold seep sediment from South China Sea. The GenBank accession numbers of the 16S rRNA gene sequence and the complete genome sequence of strain CSC1952T are OP441406 and CP128416, respectively.