Novosphingobium pentaromativorans sp. nov., a high-molecular-mass polycyclic aromatic hydrocarbon-degrading bacterium isolated from estuarine sediment

Abstract

A Gram-negative, yellow-pigmented, halophilic bacterial strain US6-1T, which degrades high-molecular-mass polycyclic aromatic hydrocarbons of two to five rings, was isolated from muddy sediment of Ulsan Bay, Republic of Korea. The 16S rRNA gene of the isolate showed high sequence similarity toNovosphingobium subarcticum(96·23 %) andSphingopyxis alaskensis(96·18 %); however, the isolate formed a distinct phyletic line within the genusNovosphingobium. DNA–DNA relatedness between US6-1Tand the closest strainN. subarcticumrevealed that strain US6-1Twas independent from this species. Isolate US6-1Thad ubiquinone 10 and a DNA G+C ratio of 61·1 mol%. Major fatty acids were octadecanoic acid (18 : 1ω7), hexadecanoic acid (16 : 1ω7) and 2-hydroxy-myristic acid (14 : 0 2-OH). On the basis of polyphasic taxonomic evidence, strain US6-1Tis proposed to represent a novel species in the genusNovosphingobiumfor which the nameNovosphingobium pentaromativoranssp. nov. is proposed. The type strain is US6-1T(=KCTC 10454T=JCM 12182T).