Phylogenetic Analysis of the Genus Actinomyces Based on 16S rRNA Gene Sequences: Description of Arcanobacterium phocae sp. nov., Arcanobacterium bernardiae comb. nov., and Arcanobacterium pyogenes comb. nov.

Abstract

A systematic phylogenetic analysis of the genus Actinomyces was performed. The 16S rRNA gene sequences of 13 Actinomyces species, an unnamed Actinomyces strain (ATCC 49338), and an Actinomyces-like isolate from sea mammals were determined. Comparative sequence analysis with closely related taxa revealed phylogenetic diversity and internal structure within the genus Actinomyces. In addition, some members of other genera (viz., the genera Arcanobacterium, Mobiluncus, and Rothia) were shown to be phylogenetically intermixed with the Actinomyces species. It was evident from both distance and tree topology considerations that the genus Actinomyces is in urgent need of taxonomic revision and requires subdivision into several genera. Based on the results of the present study it is proposed that Actinomyces bernardiae and Actinomyces pyogenes be assigned to the genus Arcanobacterium as Arcanobacterium bernardiae comb. nov. and Arcanobacterium pyogenes comb. nov., respectively. In addition, a new species, Arcanobacterium phocae, is proposed for Actinomyces-like bacteria isolated from seals.

Trueperella bernardiae: first report of wound infection post laparoscopic surgery

“…Colonies are circular, smooth, and slightly convex with a glassy appearance and diameters range from 0.2 to 0.5 mm 1.…”

“…was proposed 3. It was classified as part of the genus Arcanobacterium 1 and was later reclassified as part of the genus Trueperella 4.…”

Actinomyces bowdenii sp. nov., isolated from canine and feline clinical specimens

“…In Bergey's Manual of Systematic Bacteriology (Schaal, 1986), 10 species were included in the genus Actinomyces, with two additional organisms listed as species incertae sedis. Since Bergey's Manual o j Systematic Bacteriology was published, knowledge of the phylogenetic interrelationships of members of the genus Actinomyces has improved considerably (Pascual Ramos et al, 1997). In particular, comparative 16s rRNA gene sequencing has shown that the genus Actinomyces is phylogenetically very heterogeneous.…”

Actinomyces catuli sp. nov., from dogs.

“…Much less is known about the range of Actinomyces-like organisms in domestic and wild animals. There are, however, indications (Pascual et al, 1997a(Pascual et al, , 1999 veterinary organisms will result in the recognition of much greater Actinomyces diversity, leading to a better understanding of their host distribution and clinical significance. In this article, we report the characteristics of two strains of an unusual Actinomyces species isolated from dogs.…”

“…The genus Actinomyces as presently defined is not monophyletic and consists of several rRNA lineages worthy of separate generic status (Pascual et al, 1997a(Pascual et al, , 1999. The type species of the genus, Actinomyces bovis, falls into a distinct and robust rRNA cluster which embraces several species (viz : Actinomyces bowdenii, Actinomyces denticolens, Actinomyces howellii, Actinomyces gerencseriae, Actinomyces israelii, Actinomyces naeslundii, Actinomyces slackii, Actinomyces urogenitalis and Actinomyces viscosus) which can be regarded as the genus Actinomyces sensu stricto.…”