Gramella crocea sp. nov., isolated from activated sludge of a seafood processing plant.

A novel aerobic Gram-negative strain, designated as YB25, was isolated from an activated sludge sample collected from a seafood processing plant in Zhoushan, Zhejiang Province, China, and characterized by using a polyphasic taxonomic approach in this study. Strain YB25 was motile by gliding, and short-rod-shaped. The isolate grew at 4-37 °C (optimum 28 °C), pH 6.0-9.0 (optimum pH 7.0) and 0.0-10.0% NaCl (optimum 2.0%, w/v). Phylogenetic analysis based on 16S rRNA gene indicated that strain YB25 belonged to the genus Gramella, and showed the highest sequence similarity of 97.59% to Gramella lutea YJ019. The DNA G + C content was 39.5%. In silico DNA-DNA hybridization (DDH) and average nucleotide identity (ANI) values between strain YB25 with most closely strains were below the threshold, which is considered to the phylogenetic definition of a novel species. Chemotaxonomic analysis indicated that the only respiratory quinone was menaquinone-6 and the major fatty acids were iso-C, anteiso-C, iso-C 3-OH, and summed feature 9 (iso-Cω9c and C 10 methyl). The polar lipid profile was composed of phosphatidylethanolamine, an unidentified phospholipid, two unidentified amino lipids, three unidentified glycolipids, and four unidentified lipids. Compared with the reference strains, strain YB25 contained higher abundance of genes for carbohydrates metabolism,nitrogen metabolism, sulfur metabolism and respiration based on its genomic metabolic pathways and had been found a certain potential in the degradation of pectin. On the basis of the taxonomic evidence, strain YB25 represents a novel species of the genus Gramella, for which the name Gramella crocea sp. nov. is proposed. The type strain is YB25 (= KCTC 82680 = MCCC 1K05761).