Actinomyces viscosus

RANK: Species

TAXONOMY: Terrabacteria group -> Actinobacteria -> Actinobacteria -> Actinomycetales -> Actinomycetaceae -> Actinomyces -> Actinomyces viscosus


Actinomyces naeslundii II sequences are essentially identical to A. viscosus. The reference strain for this taxon is that for the type strain of A. viscosus, which is a hamster isolate. Strains from animals are often different than those from humans, however, in this case, there appear to be a human taxon with high sequence similarity to the hamster strain. The Oral phylotypes 169, 170, 171, 175, 176, and 688 cluster together and all are probably members of the species Actinomyces naeslundii (a fuzzy group). At this time, the Dewhirst laboratory has not examined whether strains classified as A. naeslundii genospecies 1 or 2 fall consistently into particular phylotypes in this cluster. The taxonomy of this group is is discussed in the references [1-3]. Over the next year, we will be sequencing a number of actinomyces strains from the Moores' collection, and should be able to clarify these issues.There is a vast literature on Actinomyces naeslundii which we will not attempt to review here.Easily cultivatedMoores' Collection included 34 isolatesCommon member of dental plaqueAppears to contribute to periodontal disease. Can be invasive and cause actinomycotic infections throughout the body. Identified as a constituent of the oral microbiome by Human Oral Microbiome Database. Identified as constituent of vaginal microbiome. [PMID:23282177]

This species has been identified as a resident in the human gastrointestinal tract based on the phylogenetic framework of its small subunit ribosomal RNA gene sequences.[PMC 4262072]

Gut associated
Oral microbiome
Vaginal microbiome