Abstract
A novel aerobic bacterial strain, designated as Acinetobacter zhairhuonensis sp. nov. A7.4(T), was isolated from East China Sea sediments near Zhairuo island. Cells were Gram-stain-negative, non-motile short rods, forming milky, moist colonies. Growth occurred at 10-35 °C, pH 6.0-9.0 and 0-5% NaCl concentrations (w/v). Strain A7.4(T) was catalase-positive and oxidase-negative. Major fatty acids (>10%) included summed feature 3 (C(16:1) ω7c/C(16 :1) ω6c), C(18:1) ω9c and C(16:0). The polar lipid profile comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two phospholipids and two aminolipids. Ubiquinone Q-9 and Q-8 predominated. The genome (3.57 Mb, 41.3 mol% GC) included one chromosome and a plasmid. The core-genome phylogeny placed A7.4(T) within Acinetobacter, forming a distinct clade with Acinetobacter kanungonis PS-1(T), Acinetobacter tibetensis Y-23(T) and Acinetobacter tandoii CIP107469(T). Average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA-DNA hybridization (dDDH) values between strain A7.4(T) and 87 validly published Acinetobacter species were below species thresholds (96% ANI/AAI, 70% dDDH). Phenotypic, genomic and chemotaxonomic data support the proposal of Acinetobacter zhairhuonensis sp. nov., with type strain A7.4(T) (=MCCC 1K07162(T)=LMG 32567(T)).