title: Potential pathogenic properties of members of the "Streptococcus milleri" group in relation to the production of endocarditis and abscesses.
abstract: The "Streptococcus milleri" (SMG) group have been shown to possess factors in vitro that may be involved in pathogenesis. All SMG strains are able to bind fibronectin via a cell-surface protein; the binding ranged from 12 to 198 mol/cell. Strains also bound to platelet-fibrin or fibrin clots and fibrinogen, giving maximum adhesion values of 16.5%, 21.8% and 151 mol/cell respectively. Members of the species S. constellatus produced thrombin-like activity. Lancefield group C SMG aggregated rat platelets, a bacterial cell-surface protein acting as mediator in the reaction. Most of the in-vitro factors did not correlate with each other, an indication that SMG strains possess a wide variety of pathogenic properties that may be involved in the production of abscesses or endocarditis. However, there was a correlation between the binding of large amounts of fibrinogen ( > 100 mol/cell) and the ability to aggregate platelets. This suggests that fibrinogen binding may aid in platelet aggregation.
mesh_terms: D000038:Abscess / Q000382:microbiology*; D000818:Animals; D001422:Bacterial Adhesion; D001792:Blood Platelets / Q000378:metabolism; D004697:Endocarditis, Bacterial / Q000382:microbiology*; D005337:Fibrin / Q000378:metabolism; D005340:Fibrinogen / Q000378:metabolism; D005353:Fibronectins / Q000378:metabolism; D010974:Platelet Aggregation; D051381:Rats; D012703:Serotyping; D013290:Streptococcal Infections / Q000382:microbiology*; D013291:Streptococcus / Q000145:classification / Q000472:pathogenicity* / Q000502:physiology*; D013499:Surface Properties
chemical_list: D005353:Fibronectins; D005337:Fibrin; D005340:Fibrinogen