title: Purification of D-alanine carboxypeptidase from Escherichia coli B on a penicillin-Sepharose column.
abstract: 1. A soluble D-alanine carboxypeptidase from Escherichia coli strain B was purified on a p-aminobenzylpenicillin-Sepharose column. This one-step chromatography followed by an (NH4)2SO4 precipitation yielded an enzyme purified 1200-fold and some of its properties are reported. 2. The pure D-alanine carboxypeptidase was devoid of D-alanine carboxypeptidase II activity and migrated as a single protein band on analytical disc gel electrophoresis. 3. Triton X-100 in the purification procedure is an absolute requirement for obtaining a stable enzyme. 4. The enzymic activity of D-alanine carboxypeptidase was greatly affected in solution of high salt concentrations and varied somewhat with the nature of the cation tested.
mesh_terms: D000409:Alanine; D000667:Ampicillin; D002268:Carboxypeptidases / Q000302:isolation & purification*; D011232:Chemical Precipitation; D002846:Chromatography, Affinity; D004589:Electrophoresis, Disc; D004926:Escherichia coli / Q000201:enzymology*; D011092:Polyethylene Glycols; D012685:Sepharose; D012965:Sodium Chloride
chemical_list: D011092:Polyethylene Glycols; D012965:Sodium Chloride; D000667:Ampicillin; D012685:Sepharose; D002268:Carboxypeptidases; D000409:Alanine