Pseudomonas benzopyrenica sp. nov., isolated from soil, exhibiting high-efficiency degradation of benzo(a)pyrene

Abstract

A Gram-negative, yellow-pigmented, aerobic and rod-shaped bacterium, designated as strain BaP3 T , was isolated from the soil. Strain BaP3 T grew at 16–37℃ (optimum, 30 °C) and pH 6.0–8.0 (optimum, pH 7.0). Additionally, strain BaP3 T could tolerate NaCl concentrations in the range 0–6 % (optimum, 1%). Moreover, strain BaP3 T was motile by flagella. The phylogenetic analysis of 16S rRNA sequences showed that strain BaP3 T belonged to the genus Pseudomonas , and the sequence was most closely related to Pseudomonas oryzihabitans CGMCC 1.3392 T and Pseudomonas psychrotolerans DSM 15758 T , with 99.66 % sequence similarity. Pseudomonas rhizoryzae RY24 T was the next closely related species, exhibiting 99.38 % 16S rRNA gene sequence similarity. The DNA–DNA hybridization and average nucleotide identity values between strain BaP3 T and its closely related types were below 50 and 92 %, respectively. Both results were below the cut-off for species distinction. The genomic DNA G+C content of strain BaP3 T was 65.30 mol%. The predominant quinone in strain BaP3 T was identified as ubiquinone Q-9. The major cellular fatty acids were summed feature 8 (C 18 : 1 ω 7 c and/or C 18 : 1 ω 6 c ), summed feature 3 (C 16 : 1 ω 7 c and/or C 16 : 1 ω 6 c ) and C 16 : 0 . These results indicated that strain BaP3 T represents a novel species in the genus Pseudomonas . The type strain is BaP3 T (CCTCC AB 2022379 T =JCM 35914 T ), for which the name Pseudomonas benzopyrenica sp. nov. is proposed.