Acinetobacter refrigeratorensis sp. nov., Isolated from a Domestic Refrigerator

A Gram-negative bacterial strain, designated WB1^T, was isolated from a domestic refrigerator in Guangzhou, PR China. Cells of strain WB1^T were oxidase-negative, catalase-positive, strictly aerobic, non-spore-forming and non-motile coccobacilli with peritrichous fimbriae-like structures. The strain was able to grow at 10–40 °C with optimum growth at 28–30 °C, pH 6.0–8.0 (optimum, pH 7.0) and 0–6 % NaCl (w/v, optimum, 0.5 %). Phylogenetic analyses based on 16S rRNA gene and rpoB gene sequences revealed that strain WB1^T belonged to the genus Acinetobacter and was most closely related to A. indicus DSM 25388^T (97.2 % 16S rRNA gene sequence similarity) and A. radioresistens NBRC 102413^T (96.8 %). The DNA G + C content of strain WB1^T was 46.74 ± 0.04 mol % and the major fatty acids comprised summed feature 3 (C_16:1 ω7c and/or C_16:1 ω6c), C_18:1 ω9c, C_16:0 and C_12:0. The predominant respiratory quinone was identified as Q-9 and the polar lipids as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and an unidentified phospholipid. Phenotypic, phylogenetic and chemotaxonomic data, including low DNA–DNA relatedness with closely related type strains, supported that strain WB1^T represents a distinct novel species in the genus Acinetobacter, for which the name Acinetobacter refrigeratorensis sp. nov. was proposed. The type strain is WB1^T (=GIMCC 1.663^T = CCTCC AB 2014197^T = KCTC 42011^T).