title: Vitamin B6-responsive and -unresponsive cystathioninuria: two variant molecular forms.
abstract: Cystathionase activity in a lymphoid cell line extracts from a vitamin B6-responsive patient with cystathioninuria was increased strikingly by pyridoxal phosphate. Immunodiffusion with antiserum to human hepatic cystathionase showed identity between this cystathionase protein and cystathionase from an extract of normal lymphoid cells. Neither an increase in cystathionase activity nor immunochemical identity was found using extract of cells from a B6-unresponsive patient.
mesh_terms: D000592:Amino Acid Metabolism, Inborn Errors / Q000188:drug therapy / Q000201:enzymology* / Q000235:genetics; D002460:Cell Line; D003429:Cross Reactions; D003540:Cystathionine / Q000652:urine; D003542:Cystathionine gamma-Lyase / Q000172:deficiency* / Q000276:immunology; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D006801:Humans; D008190:Lyases / Q000172:deficiency*; D009154:Mutation; D011732:Pyridoxal Phosphate / Q000494:pharmacology; D011736:Pyridoxine / Q000627:therapeutic use*
chemical_list: D003540:Cystathionine; D011732:Pyridoxal Phosphate; D008190:Lyases; D003542:Cystathionine gamma-Lyase; D011736:Pyridoxine