Actinomyces canis sp nov., isolated from dogs

Three strains of a previously undescribed catalase-positive Actinomyces-lik e bacterium were isolated from dogs. Biochemical testing and PACE analysis of whole-cell proteins indicated that the strains were phenotypically highl y related to each other but different from previously described Actinomyces and Arcanoibacterium species. Sequencing of 16S rRNA showed that the unkno wn bacterium represents a new subline within a cluster of species which inc ludes Actinomyces hyovaginalis. Actinomyces georgiae. Actinomyces meyeri, A ctinomyces odontolyticus, Actinomyces radingae and Actinomyces turicensis. On the basis of phenotypic evidence and 16S rRNA sequence divergence levels (greater than 5% with recognized Actinomyces species) it is proposed that the unknown strains from canine sources be classified as a new species with the name Actinomyces canis sp, nov. The type strain of Actinomyces canis i s CCUC 41706(T) (= CIP 106351(T)).