A) Larger S. aureus colonies with a yellow pigment (staphyloxanthin) along with small white S. epidermidis and grey Enterococcus faecalis colonies
B) S. aureus causing beta-haemolysis on sheep blood agar, incubated at 37°C for 48h. The clearing of the erythrocytes in the agar is demonstrated by text underneath the plate being easily readable.
C) S. aureus beta-haemolysis on sheep blood agar, incubated at 37°C for 24h
D) "Hot-cold" haemolysis: a characteristic of staphylococcal beta-haemolysin, where clearing is strengthened if the colonies are kept at a cold temperature after growth. Incubated for 24 h at 37°C and then for 24 h at 8°C.
Text: Eva van Dijk