.
Species of Streptococcus are classified based on their hemolytic properties. Hemolysis refers to the ability of the bacteria to break down red blood cells. There are three types of hemolysis: alpha, beta, and gamma. Alpha-hemolytic species cause oxidization of iron in hemoglobin molecules within redRead more
Species of Streptococcus are classified based on their hemolytic properties. Hemolysis refers to the ability of the bacteria to break down red blood cells. There are three types of hemolysis: alpha, beta, and gamma. Alpha-hemolytic species cause oxidization of iron in hemoglobin molecules within red blood cells, giving it a greenish color on blood agar. Beta-hemolytic species cause complete rupture of red blood cells. Gamma-hemolytic species do not cause hemolysis at all.
See less
Streptococcus is a genus of gram-positive coccus or spherical bacteria that belongs to the family Streptococcaceae, within the order Lactobacillales (lactic acid bacteria), in the phylum Bacillota. In the medical setting, the most important groups are the alpha-hemolytic streptococci S. pneumoniae aRead more
Streptococcus is a genus of gram-positive coccus or spherical bacteria that belongs to the family Streptococcaceae, within the order Lactobacillales (lactic acid bacteria), in the phylum Bacillota. In the medical setting, the most important groups are the alpha-hemolytic streptococci S. pneumoniae and Streptococcus viridans group, and the beta-hemolytic streptococci of Lancefield groups A and B (also known as “group A strep” and “group B strep”).
Streptococci infections are divided into several groups: Group A streptococcus, Group B streptococcus, Group C streptococcus, and Group G streptococcus. Group A strep, sometimes called GAS, tends to affect the throat and the skin. People may carry GAS in these areas yet not show any symptoms of illness. Most group A strep infections cause relatively mild illness, but on rare occasions, these bacteria can lead to severe and even life-threatening diseases.
See less