Taylorella asinigenitalis sp nov., a bacterium isolated from the genital tract of male donkeys (Equus asinus)

Three bacterial isolates that were phenotypically indistinguishable from Ta ylorella equigenitalis were obtained from the urethral fossae of three male donkeys (Equus asinus), one located in the state of California and the oth er two in the state of Kentucky, USA. Based on results of pulsed-field gel electrophoresis, the isolate from California differed from the two Kentucky isolates, which were the same. Mares bred artificially (California) or nat urally (Kentucky) did not show signs of disease, even though infection with the organism was established in those bred naturally. Mares and, uncharact eristically, all three jacks produced antibodies that reacted in the comple ment fixation test utilized to identify mares recently infected with T. equ igenitalis. Sequence analysis of DNA encoding the 16S rRNA revealed that th e gene sequences of these isolates were virtually identical to each other ( > 99.8 % similarity), but different (97.6 % similarity) from those of sever al confirmed isolates of T. equigenitalis. The 16S rDNA sequences of the la tter were 100% identical. DNA-DNA hybridization studies revealed a mean hyb ridization level of 89 % between the donkey isolate from California and the donkey isolate from Kentucky. On the other hand, the mean DNA-DNA hybridiz ation level from the donkey isolates with DNA from a strain of T. equigenit alis was 23 %. The DNA G+C composition was 37.8 mol% for the two donkey iso lates, as well as the strain of T. equigenitalis used in the hybridization studies. These data support our opinion that micro-organisms isolated from the male donkeys are different from T. equigenitalis and it is proposed tha t they be considered a new species within the genus Taylorella and named Ta ylorella asinigenitalis sp. nov. The type strain is strain UCD-1(T) (= ATCC 700933(T) = LMG 19572(T)).