Actinomyces

Actinomyces /Ac·ti·no·my·ces/ (-mi´sēz) a genus of bacteria (family Actinomycetaceae).

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Actinomyces israe´lii  a species parasitic in the mouth, proliferating in necrotic tissue; it is the etiologic agent of human actinomycosis and can cause actinomycotic mycetoma.

Actinomyces naeslun´dii  an anaerobic species that is a normal inhabitant of the oral cavity and a cause of human actinomycosis and periodontal disease.

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Ac·ti·no·my·ces (kt-n-msz)

n.

A genus of nonmotile, non-spore-producing, anaerobic to facultatively anaerobic bacteria pathogenic to humans.

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Actinomyces

[ak′tinōmī′sēz] , pl. actinomycetes

Etymology: Gk, aktis, ray, mykes, fungus

a genus of anaerobic or facultative anaerobic, gram-positive bacteria. Species that may cause disease in humans, such as Actinomyces israelii (which causes actinomycosis), are normally present in the mouth and throat. Disease activity is normally limited to periodontal disease.

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Actinomyces [ak″tĭ-no-mi´sēz]

a genus of gram-negative, non–acid fast, nonmotile bacteria that form branched filaments. It includes A. israe´lii and A. naeslun´dii, both of which cause human actinomycosis and periodontal disease.

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actinomyces [ak″tĭ-no-mi´sēz]

an organism of the genus Actinomyces. adj., adj actinomycet´ic.

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actinic cheilitis (aktin´ik),

n See cheilitis, actinic.

Actinobacillus,

n a genus of nonmobile, gram-negative aerobic and facultatively anaerobic bacteria of the family Brucellaceae.

Actinomyces

n.pl filamentous microorganisms that have been implicated in the formation of dental calculus and serve as a mode of attachment of dental calculus to the tooth surface. These microorganisms have also been found in pathologic lesions of the alveolar processes (actinomycosis).

A. israelii

n.pl a normally occurring oral bacteria that aggressively causes infection (actinomycosis) when oral health is compromised.

A. naeslundii

n a specific strain of bacteria resident in open sores in the oral cavity.

A. viscosus,

n a species of
Actinomyces occurring in high numbers in the dental plaque, cemental caries, and tonsillar crypts.

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Actinomyces

a genus of non-acid-fast, gram-positive organisms that form a mycelium of branching filaments that fragment into irregular-sized fragments.

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Actinomyces bovis

the cause of actinomycosis of cattle and sheep.

Actinomyces congolensis, Actinomyces dermatonomus

see dermatophiluscongolensis.

Actinomyces hordeovulneris

a cause of abscesses, pleuritis and systemic infections in dogs where it is often associated with penetration by grass awns (foxtails) of Hordeum spp.

Actinomyces israelii

an uncommon cause of actinomycosis in cattle and pigs.

Actinomyces necrophorus

see fusobacteriumnecrophorum.

Actinomyces pyogenes

now called Arcanobacterium pyogenes.

Actinomyces suis

the cause of actinomycosis of the swine mammary gland.

Actinomyces viscosus

the cause of periodontal disease in hamsters, and opportunistic infections of dogs.

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actinomyces

an organism of the genus Actinomyces.

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Actinomyces

Microbiology A genus of slow-growing, facultatively anaerobic, nonmotile, nonspore-forming, gram-positive bacteria, which form branching, irregularly staining filaments, filamentous microcolonies, and metabolize by fermentation of certain sugars. See Actinomycosis, Sulfur granules. Cf Bacteroides spp, Nocardiaspp.