Escherichia coli on SMAC agar

Escherichia coli on SMAC agar

Culture of two Escherichia coli strains on sorbitol-MacConkey (SMAC) agar. Most E. coli utilize sorbitol (red colonies on right), but E. coli O157:H7 cannot (colorless colonies on left).

Courtesy of Harriet Provine.

Graphic 82227 Version 4.0