title: Formation of  -cyanoalanine by O-acetylserine sulfhydrylase.
abstract: Cell-free extracts of Bacillus megaterium form beta-cyanoalanine (beta-CNA)-(14)C from Na(14)CN and l-cysteine, O-acetyl-l-serine or, to a lesser extent, l-serine. However, the presence of cyanide in the growth medium does not increase the capacity of cell extracts to catalyze the formation of beta-CNA from cysteine and cyanide. The formation of beta-CNA is readily detected in extracts of cells grown in synthetic media with sulfate or l-djenkolic acid as sulfur sources; such cells also exhibit an increased ability to form cysteine when compared with cells grown on cysteine as the sulfur source. beta-CNA formation could not be detected in extracts of cells grown on cysteine as the sulfur source. A 40-fold purification of the O-acetyl-serine sulfhydrylase resulted in the co-purification of the beta-CNA-forming activity. The sulfhydrylase and the beta-CNA-forming activity co-chromatographed on diethyl-aminoethyl cellulose and Sephadex G-100.
mesh_terms: D000085:Acetates; D000409:Alanine / Q000096:biosynthesis*; D000645:Ammonium Sulfate; D001410:Bacillus megaterium / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D002247:Carbon Isotopes; D002474:Cell-Free System; D011232:Chemical Precipitation; D002848:Chromatography, DEAE-Cellulose; D003124:Colorimetry; D003470:Culture Media; D003486:Cyanides / Q000096:biosynthesis* / Q000378:metabolism; D003545:Cysteine / Q000378:metabolism; D008190:Lyases / Q000302:isolation & purification / Q000378:metabolism*; D011479:Protamines; D012694:Serine / Q000378:metabolism; D013431:Sulfates / Q000378:metabolism
chemical_list: D000085:Acetates; D002247:Carbon Isotopes; D003470:Culture Media; D003486:Cyanides; D011479:Protamines; D013431:Sulfates; D012694:Serine; D008190:Lyases; D003545:Cysteine; D000409:Alanine; D000645:Ammonium Sulfate