Sinorhizobium morelense sp. nov., a Leucaena leucocephala-associated bacterium that is highly resistant to multiple antibiotics

Sinorhizobium morelense sp. nov. is described to designate a group of bacteria isolated from root nodules of Leucaena leucocephata. S. morelense shows 98% 16S rRNA gene sequence similarity to some Sinorhizobium species and to Ensifer adhaerens. This novel species is distinguished from other Sinorhizobium species and from E. adhaerens by DNA-DNA hybridization, 16S rRNA gene restriction fragments and sequence and some distinctive phenotypic features. Strains of this species are highly resistant to some antibiotics, such as carbenicillin (1 mg ml^-1), kanamycin (500 μg ml^-1) and erythromycin (300 μg ml^-1). They do not form nodules, but a nodulating strain, Lc57, is closely related to the novel species. Strain Lc04^T (= LMG 21331^T = CFN E1007^T) is designated as the type strain of this novel species.