Actinomyces canis sp nov., isolated from dogs

Three strains of a previously undescribed catalase-positive Actinomyces-like bacterium were isolated from dogs. Biochemical testing and PACE analysis of whole-cell proteins indicated that the strains were phenotypically highly related to each other but different from previously described Actinomyces and Arcanoibacterium species. Sequencing of 16S rRNA showed that the unknown bacterium represents a new subline within a cluster of species which includes Actinomyces hyovaginalis. Actinomyces georgiae. Actinomyces meyeri, Actinomyces 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 is CCUC 41706(T) (= CIP 106351(T)).