Actinobacillus(redirected from Actinobacillus actinomycetem-comitans)
Also found in: Dictionary, Medical.
A genus of gram-negative, immotile and nonspore-forming, oval to rod-shaped, often pleomorphic bacteria which occur as parasites or pathogens in mammals (including humans), birds, and reptiles. They are facultatively aerobic, capable of fermenting carbohydrates (without production of gas) and of reducing nitrates. The genomic DNA contains between 40 and 47 mol % guanine plus cytosine. The actinobacillus group shares many biological properties with the genus Pasteurella. See Pasteurella
Actinobacillus (Pasteurella) ureae and A. hominis occur in the respiratory tract of healthy humans and may be involved in the pathogenesis of sinusitis, bronchopneumonia, pleural empyema, and meningitis. Actinobacillus actinomycetemcomitans occurs in the human oral microflora, and together with anaerobic or capnophilic organisms may cause endocarditis and suppurative lesions in the upper alimentary tract. Actinobacilli are susceptible to most antibiotics of the β-lactam family, aminoglycosides, tetracyclines, chloramphenicol, and many other antibacterial chemotherapeutics. See Antibiotic, Medical bacteriology