Unknown organism, presumable yeast, seen on Bile Esculin Agar (BEA) after several months at refrigerated temperatures. Organism was mucoid.circular, and a light brown in color. The brown coloration around the colony indicates the organism can to convert the esculin into 6,7-dihydroxy-couarin producing the black pigment in the agar.
Violet stained gram-positive cocci and pink stained gram-negative rod-shaped bacteria
Final lab, ex.6. Phenylalanine deamination. Some Gram-negative bacteria can oxidatively deaminate the amino acid phenylalanine to produce phenylpruvic acid and ammonia. The reaction is catalyzed by the enzyme phenylalanine deamninase. This enzyme can be detected by adding ferric chloride which forms a green complex. Reagent: Ferric chloride.