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

Abstract

A novel aerobic Gram-negative strain, designated as YB25T, 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 YB25T 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 YB25T belonged to the genus Gramella, and showed the highest sequence similarity of 97.59% to Gramella lutea YJ019T. The DNA G + C content was 39.5%. In silico DNA-DNA hybridization (DDH) and average nucleotide identity (ANI) values between strain YB25T 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-C15:0, anteiso-C15:0, iso-C17:0 3-OH, and summed feature 9 (iso-C17:1ω9c and C16:0 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 YB25T 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 YB25T represents a novel species of the genus Gramella, for which the name Gramella crocea sp. nov. is proposed. The type strain is YB25T (= KCTC 82680T = MCCC 1K05761T).