Nocardia coubleae sp. nov., isolated from oil-contaminated Kuwaiti soil

Two bacterial isolates from Kuwaiti soil contaminated by crude oil were analysed by using a polyphasic taxonomic approach. The isolates, designated OFN N11 and OFN N12(T), were shown to have molecular, chemical and morphological properties typical of members of the genus Nocardia. Based on a multigenic approach that included 16S rRNA, hsp65 and sod gene sequencing, these novel isolates formed a monophyletic clade within the genus Nocardia. The closest species was Nocardia ignorata (with 99.4 %, 99.5 %, 98.6 % gene sequence similarity to the 16S rRNA, hsp65 and sod genes, respectively). The novel isolates could be distinguished phenotypically from the type strains of recognized species of the genus Nocardia. The novel isolates were not related to the type strain of N. ignorata in DNA-DNA hybridization experiments (26 % relatedness). On the basis of these genotypic and phenotypic data, the two isolates appear to represent a novel species, for which the name Nocardia coubleae sp. nov. is proposed. The type strain is OFN N12(T) (=DSM 44960(T)=CIP 108996(T)).