Castellaniella daejeonensis sp. nov., isolated from soil

A Gram-negative, non-spore-forming, motile, facultatively anaerobic bacterium, designated strain MJ06(T), was isolated from oil-contaminated soil and was characterized taxonomically by using a polyphasic approach. Strain MJ06(T) contained ubiquinone Q-8 as the major respiratory lipoquinone, putrescine as the predominant polyamine and phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol as major polar lipids. The G+C content of the genomic DNA of strain MJ06(T) was 66.2 mol%. The major fatty acids were summed feature 4 (C(16 : 1)ω 7c and/or iso-C(15 : 0) 2-OH; 32.5 %), C(16 : 0) (22.8 %) and summed feature 7 (one or more of C(18 : 1)ω 7c, C(18 : 1)ω 9t and C(18 : 1)ω 12t; 14.9 %). Comparative 16S rRNA gene sequence analysis showed that strain MJ06(T) belonged to the family Alcaligenaceae, class Betaproteobacteria, and joined the evolutionary radiation enclosed by the genus Castellaniella. Levels of 16S rRNA gene sequence similarity between strain MJ06(T) and its phylogenetically closest relatives, Castellaniella denitrificans NKNTAU(T), Castellaniella defragrans 54Pin(T), Castellaniella ginsengisoli DCY36(T) and Castellaniella caeni Ho-11(T), were 98.6, 98.3, 97.8 and 97.3 %, respectively. Levels of similarity between strain MJ06(T) and the type strains of all other recognized species in the family Alcaligenaceae were below 95.0 %. Strain MJ06(T) exhibited relatively low levels of DNA-DNA relatedness with respect to C. defragrans DSM 12141(T) (52 %), C. denitrificans DSM 11046(T) (31 %), C. ginsengisoli KCTC 22398(T) (18 %) and C. caeni KCTC 12197(T) (15 %). On the basis of its phenotypic and genotypic properties together with phylogenetic distinctiveness, strain MJ06(T) is considered to represent a novel species of the genus Castellaniella, for which the name Castellaniella daejeonensis sp. nov. is proposed. The type strain is MJ06(T) (=KCTC 22454(T) =JCM 16240(T)).