ActinomycesDid we forget anything? Let us know

Genus nameActinomyces
Alternative names
NCBI taxonomy ID1654

Taxonomy (MiDAS 2.0)


16S gene copy number1-5

 In situOther
Hydrophobic cell surface89

CLSM images of in situ biofilm on glass surfaces (x-y sections). Biofilms were stained simultaneously with all-bacterium-specific EUB338 probe, Streptococcus-specific STR405 probe and Actinomyces-specific ACT476 probe. Green (yellow), blue (purple) and red represent streptococci, A. naeslundii and the remaining bacteria, respectively. Images of the microbial colonization pattern after 6 h (d, e) in four different individuals, showing solitary bacteria and bacteria in clusters. A. naeslundii was observed in mixed clusters with other bacteria. Panels (d) and (e) are maximum projection images. Scale bar for all images, 10 microns. - Source:5

Aerobic heterotroph

POSNEGVariableNot assessed


The genus Actinomyces, contains a group of organisms which do not conform to a single criterion or definition. Species in the genus demonstrate considerable variation in their physiology 6. Generally, they are chemoorganotrophs, with a fermentative metabolism 6. Carbohydrates are preferred sources of carbon for energy and growth 6. A wide range of carbohydrates are utilized, but species may vary in their carbohydrate utilizing ability 6. Acetate, lactate, succinate and formate are end products of glucose fermentation 6. Oxygen requirements vary considerably between species 6. Growth occurs under anaerobic conditions, however Actinomyces can be facultatively anaerobic in the presence of 5% CO2 atmosphere or aerotolerant 6. Considerable variability also occurs with respect to cell morphology, between species and between strains within the same species 6. Cells of the type species of the genus A. bovis, appear as straight to slightly curved rods 6. In some spp. rods may show branching and in others they may develop into filamentous branching forms 6. Coccoid or coccobacillary forms can also occur in some species 6. Microcolonies may also occur 6. No in situ information has been determined for the genus in activated sludge, however certain members of the genus have been implicated in biofilm formation in the oral cavity and as initial colonizers of tooth surfaces 5.

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FISH probes

Probe JF201 (A. naeslundii species-specific probe) 7; ACT476 (species-specific probe for A. naeslundii- A. viscosus- A. bowdeni- A. denticolens) 5


 In situOther
Aerobic Heterotroph6
Nitrite Reduction
Sulfate Reduction
Short-chain Fatty Acids
Proteins/Amino Acids

Abundance Information

 10 % percentileMedian90 % percentile
Activated Sludge00.10.2

Predominant InInfluent


[1] - NCBI genome database, NCBI id 1654 -

[2] McLean, Liu, Bor, Bedree, Cen, Watling, et al. (2016): Draft Genome Sequence of Actinomyces odontolyticus subsp. actinosynbacter Strain XH001, the Basibiont of an Oral TM7 Epibiont. Genome Announc 4 (1): . doi:10.1128/genomeA.01685-15

[3] Roux, Robert, Gimenez, Gharbi, Raoult (2012): Draft genome sequence of Actinomyces massiliensis strain 4401292T. J. Bacteriol. 194 (18): 5121. doi:10.1128/JB.01039-12

[4] Gorlas, Gimenez, Raoult, Roux (2012): Draft genome sequences of Actinomyces timonensis strain 7400942T and its prophage. J. Bacteriol. 194 (23): 6613-4. doi:10.1128/JB.01730-12

[5] Dige, Raarup, Nyengaard, Kilian, Nyvad (2009): Actinomyces naeslundii in initial dental biofilm formation. Microbiology (Reading, Engl.) 155 (Pt 7): 2116-26. doi:10.1099/mic.0.027706-0

[6] Atteyet-Alla Fetouh, Yassin (2014) The family Actinomycetaceae. In: E. Rosenberg., E.F DeLong., S. Lory., E. Stackebrandt., and F. Thompson. The Prokaryotes: Actinobacteria. Pp 21-103. Springer, Berlin, Heidelberg. - Atteyet-alla Fetouh 2014docx -

[7] Foster, Kolenbrander (2004): Development of a multispecies oral bacterial community in a saliva-conditioned flow cell. Appl. Environ. Microbiol. 70 (7): 4340-8. doi:10.1128/AEM.70.7.4340-4348.2004

[8] van der Mei, H.C., and Busscher, H.J. (1998) A reference guide to microbial cell surface hydrophobicity based on contact angles. Colloids and surfaces B: Biointerfaces. 11: 213-221. - Van Der Mei And Busscher 1998docx -

[9] Schlafer, Meyer, Sutherland, Städler (2012): Effect of osteopontin on the initial adhesion of dental bacteria. J. Nat. Prod. 75 (12): 2108-12. doi:10.1021/np300514z

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