Labrenzia suaedae sp. nov., a marine bacterium isolated from a halophyte, and emended description of the genus Labrenzia

Abstract

An endophytic, Gram-staining-negative bacterium was isolated from sterilized roots of a plant, Suaeda maritima, growing on tidal flats. Cells of the strain were motile by means of a single polar flagellum and colonies were pigmented light brown. Strain YC6927T was able to grow at 15-37 °C (optimum at 28-30 °C) and at pH 5.0-10.0 (optimum at pH 7.0-8.0). The strain was able to grow at NaCl concentrations of 0-9.0 % (w/v), with optimum growth at 0-5.0 % NaCl. Comparison of 16S rRNA gene sequences showed that the strain was a member of the genus Labrenzia, exhibiting the highest similarity to Labrenzia marina mano18T (97.6 % sequence similarity). Strain YC6927T produced light-brown carotenoid pigments. The major respiratory quinone was Q-10 and the DNA G+C content was 58.5 mol%. The DNA-DNA relatedness between strain YC6927T and closely related strains was between 8.2±1.8 and 20.3±1.5 %. Strain YC6927T contained summed feature 8 (C18: 1ω7c and/or C18: 1ω6c) and C14: 0 3-OH as major fatty acids, confirming the affiliation of the strain with the genus Labrenzia. The polar lipids consisted of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylmonomethylethanolamine, an unknown aminolipid, an unknown phospholipid and five unknown lipids. On the basis of phylogenetic analysis, physiological and biochemical characterization and DNA-DNA hybridization data, strain YC6927T should be assigned to a novel species of the genus Labrenzia, for which the name Labrenzia suaedae sp. nov. is proposed. The type strain is YC6927T (= KACC 13772T = DSM 22153T). An emended description of the genus Labrenzia is also proposed. © 2014 IUMS.