Amino Acid Enzymes Enzymes that attack Amino Acids 1. Cysteine desulfhydrase 2. Lysine decarboxylase 3. Phenylalanine deaminase
Amino Acid Structure
Amino Acid Enzymes Cysteine desulfhydrase Cysteine Hydrogen Sulfide + ammonia + Pyruvic acid
Peptone Iron Agar Deeps Peptone – protein rich in cysteine Iron - Fe
Cysteine desulfhydrase Cysteine Hydrogen Sulfide + ammonia + Pyruvic acid H2S Fe (Iron) FeS (Ferrous Sulfide) Black
Cysteine desulfhydrase
Amino Acid Enzymes Lysine decarboxylase Lysine Cadaverine + Carbon dioxide
Lysine Decarboxlyase Broth Lysine Fermentable sugar ph indicator Basic = purple Acid = Yellow Durham Tube Mineral Oil on top after inoculation (maintain an Anaerobic environment)
Lysine decarboxylase broth
Amino Acid Enzymes Phenylalanine deaminase Phenylalanine Phenylpyruvic acid + ammonia
Phenylalanine deaminase Phenylalanine Phenylpyruvic acid + ammonia FeCl2 (Ferric Chloride) HCl Green
Phenylalanine Agar Slants