Staphylococcus epidermidis Growing on Columbia CNA Agar

Only Gram-positive bacteria grow on Columbia CNA agar. (Gram-negative bacteria are inhibited by the colistin and nalidixic acid added to the agar.) Staphylococcus epidermidis does not normally produce pigment.

Photograph of Staphylococcus epidermidis growing on Columbia CNA agar.jpg by Gary E. Kaiser, Ph.D.
Professor of Microbiology, The Community College of Baltimore County, Catonsville Campus
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Last updated: June, 2018
Please send comments and inquiries to Dr. Gary Kaiser