title: Assay of pyridoxal phosphate and pyridoxamine phosphate, employing S-o-nitrophenyl-L-cysteine, a chromogenic substrate of tryptophanase.
mesh_terms: D003545:Cysteine / Q000031:analogs & derivatives*; D004926:Escherichia coli / Q000201:enzymology; D008190:Lyases / Q000378:metabolism*; D009578:Nitrobenzenes; D009943:Organophosphorus Compounds / Q000032:analysis; D011732:Pyridoxal Phosphate / Q000032:analysis* / Q000494:pharmacology; D011733:Pyridoxamine / Q000031:analogs & derivatives* / Q000032:analysis / Q000494:pharmacology; D014368:Tryptophanase / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D009578:Nitrobenzenes; D009943:Organophosphorus Compounds; D011732:Pyridoxal Phosphate; C019501:S-o-nitrophenyl-L-cysteine; D011733:Pyridoxamine; D008190:Lyases; D014368:Tryptophanase; D003545:Cysteine; C010627:pyridoxamine phosphate