Actinomyces naeslundii

**Semantic type:** Bacterium

**Definition:** A species of anaerobic, Gram positive, rod shaped bacteria assigned to the phylum Actinobacteria. This bacteria is urease positive, hydrolyzes esculin and does not produce acid from mannitol. A. naeslundii is a commensal organism of the oral cavity and colonizes tooth surfaces but may cause infection and periodontal disease in cases in which oral trauma occurs.

**Synonyms:** - ACTINOMYCES NAESLUNDII