sp. nov. isolated from northern elephant seals () and sp. nov. isolated from California sea lions ().

Novel ureaplasma strains have been isolated from the genital tract of both sexes of northern elephant seals (; six strains) and California sea lions (; five strains) stranded along the Central California coast, USA. These strains were phenotypically and genetically characterized and compared to other seven known species. All novel ureaplasma strains hydrolysed urea, but did not metabolize arginine, and all were isolated and propagated using PPLO medium supplemented with urea under aerobic, microaerophilic, and anaerobic atmospheric conditions at +35-37 °C. Transmission electron microscopy revealed typical mollicute cellular morphology. Molecular characterization included assessment of the following genetic loci: 16S rRNA, the 16S-23S ITS, 23S rRNA, , , , , and . Complete 16S rRNA gene sequence analysis of these novel species indicated that they were most closely related to each other with nucleotide identity 99.87 % and ≤93.08 % related to other known species. The results of nucleotide analysis of the sequenced housekeeping genes revealed 71.68-93.02 % similarity to corresponding genes of other known species. The multi-locus genetic characterization and the phylogenetic analysis of the 16S rRNA and genes of these species clearly demonstrated their novelty and, reflecting their host specificites, the name sp. nov. is proposed for the species isolated from northern elephant seals, the type strain is ES2783-GEN (=DSM 24842=ATCC BAA-2460), and the name sp. nov. is proposed for the species isolated from California sea lions, the type strain is CSL7644-GEN (=DSM 24843=ATCC BAA-2262).