PROTEOBACTERIA >> Gamma >> Aggregatibacter >> Aggregatibacter actinomycetemcomitans

AGGREGATIBACTER ACTINOMYCETEMCOMITANS

Class: Gamma Proteobacteria
Genus: Aggregatibacter
Species: Aggregatibacter actinomycetemcomitans
Description: Small rods which may appear as cocci in broth or actinomycotic lesions. They may occur singly, in pairs or in small clumps. Grows poorly in ambient air, but well in 5% CO2. Colonies on chocolate agar are small, with a diameter of ≤0.5 mm after 24 h, but may exceed 1–2 mm after 48 h. On primary isolation, the colonies are rough-textured and adherent and have an internal, opaque pattern described as star-like or like ‘crossed cigars’. The rough phenotype is related to fimbriation and to the production of hexoseamine-containing exopolysaccharide. Cells from rough colonies grow in broth as granular, autoaggregated cells that adhere to the glass and leave a clear broth.Successive rounds of subculturing in vitro on solid media can result in transformation into a smooth, non-adherent colony type that exhibits planktonic growth in broth and reduced ability to colonize the mouth of experimental animals. X and V factors are not required.
Synonyms:
Source: isolated from human actinomycosis. It is sometimes found in other pathological processes such as endocarditis,brain abscess and urinary tract infections.
Pathogenicity:
Genbank: NZ_CP012959.1   [Genome]    [Nucleotide]
Size (Mb): 2.37
GC %: 44.2
Genes: 2,307
CDS Number: 2,230
Reference: NØRSKOV-LAURITSEN (N.) and KILIAN (M.): Reclassification of Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, Haemophilus paraphrophilus and Haemophilus segnis as Aggregatibacter actinomycetemcomitans gen. nov., comb. nov., Aggregatibacter aphrophilus comb. nov. and Aggregatibacter segnis comb. nov., and emended description of Aggregatibacter aphrophilus to include V factor-dependent and V factor-independent isolates. Int. J. Syst. Evol. Microbiol., 2006, 56, 2135-2146.
Biochemical Tests: