The symbiotic bacterium (IMI 397775T, DSM 24915T) was isolated from the insect-pathogenic nematode Steinernema australe. On the basis of 16S rRNA gene sequence similarity, this bacterial isolate was shown to belong to the genus Xenorhabdus in agreement with the genus of its nematode-host. The accurate phylogenetic position of this new isolate was defined using a multigene approach and showed that isolate IMI 397775T shares a common ancestor with X. doucetiae FRM16 T and X. romanii PR06-AT, the symbiotic bacteria associated with Steinernema diaprepesi and Steinernema puertoricense respectively. The nucleotide identity (less than 97%) between IMI 397775T, X. doucetiae FRM16T and X. romanii PR06-AT calculated on the concatenated sequences of five gene fragments encompassing 4275 nucleotides, several phenotypic traits and the difference between the upper temperatures limiting growth of these three bacteria allowed genetic and phenotypic differentiation of isolate IMI 397775T from its two closely related species. IMI 397775T therefore represents a new species, for which the name Xenorhabdus magdalenensis sp. nov. is proposed, with the type strain IMI 397775T (=DSM 24915T).
Taillez, P.; Pagès, S.; Edgington, S.; Tymo, L.T.; Buddie, A.G. Description of Xenorhabdus magdalenensis sp. nov., the symbiotic bacterium associated with Steinernema australe. INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY : [DOI: 10.1099/ijs.0.034322-0]