Facultatively anaerobic, Gram positive cocci, approximately 1 um in diameter, that grow in short chains in broth cultures. Carbohydrates are femented primarily to lactic acid and no gas. Catalase negative. Cell wall contains glycerol teichoic acid and rhamnose. Peptidoglycan type is Lys-Ala1-3 [5,6]
S. sanguis is similar to S. gordonii but can be differentiated based on the following; DNA homology, higher G+C content of the DNA (46 vs 42 mol%), doesn't ferment amygdalin, lacks alkaline phosphatase and B-glucosaminidase activities, has IgA1 protease activity, and by multilocus enzyme analysis [5,6].
4 biovars of S. sanguis differ biochemically and serologically, but all biovars possess the group H antigen