Staphylococcus aureus on CAP agar (blood agar with 5% of defibrinated sheep blood, colistin and aztreonam). Cultivation 48 hours, aerobic atmosphere, 37°C.
Colonies are surroundend by a wide zone of beta hemolysis.
S. aureus appears as grape-like clusters when viewed through a microscope, and has large, round, golden-yellow colonies, often with beta hemolysis, when grown on blood agar plates. Beta hemolysis (ß-hemolysis), sometimes called complete hemolysis, is a complete lysis of red cells in the media around and under the colonies: the area appears lightened (yellow) and transparent.
There are four Staphylococcus aureus hemolysins (alfa-hemolysin, beta-hemolysin, gamma-hemolysin and delta-hemolysin).
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