Actinomyces marimammalium sp. nov., from marine mammals.

Three strains of a previously undescribed Actinomyces-like bacterium were isolated from samples taken from two dead seals and a porpoise. Biochemical testing and PAGE analysis of whole-cell proteins indicated the strains were phenotypically similar to each other but different from previously described Actinomyces and Arcanobacterium species. Comparative 16S rRNA gene sequencing studies showed the organisms from marine animals were genetically closely related and represent a hitherto unknown subline within the genus Actinomyces (sequence divergence values > 6% with recognized species). Based on phylogenetic and phenotypic evidence it is proposed that the unknown bacterium from the seals and a porpoise should be classified as Actinomyces marimammalium sp. nov. The type strain is CCUG 41710T.