Diaphorobacter aerolatus sp. nov., isolated from air, and emended description of the genus Diaphorobacter

Abstract

A Gram-stain-negative, non-motile, aerobic rod, designated 8604S-37T, was isolated from an outdoor air sample collected in Suwon region, Republic of Korea. The isolate was catalase-positive and oxidase-negative. 16S rRNA gene sequence analysis indicated that strain 8604S-37T was most closely related to Diaphorobacter nitroreducens NA10BT and Diaphorobacter oryzae RF3T, with which it shared 97.0 % 16S rRNA gene sequence similarity. Strain 8604S-37T grew at 10–37 °C (optimum 28 °C; no growth occurred at 4 or 40 °C) and pH 5–9 (optimum pH 7). The strain tolerated up to 3 % NaCl (w/v) (optimum 0 %). The only respiratory quinone was ubiquinone-8 (Q-8). The polar lipid profile comprised phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and one unknown aminolipid. The major fatty acids were C16 : 0, summed feature 3 (comprising C16 : 1ω7c and/or iso-C15 : 0 2-OH), summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c) and C17 : 0 cyclo, and the predominant hydroxy fatty acid was C10 : 0 3-OH. Strain 8604S-37T exhibited less than 50 % DNA–DNA relatedness with Diaphorobacter nitroreducens KACC 13856T and Diaphorobacter oryzae KACC 16857T. The DNA G+C content was 65 mol%. Strain 8604S-37T represents a novel species of the genus Diaphorobacter , for which the name Diaphorobacter aerolatus sp. nov. is proposed. The type strain is 8604S-37T ( = KACC 16536T = NBRC 108926T). An emended description of the genus Diaphorobacter is also proposed.