title: A spectrophotometric assay for meso-diaminopimelate decarboxylase and L-alpha-amino-epsilon-caprolactam hydrolase.
abstract: A spectrophotometric assay for the activities of mesodiaminopimelate decarboxylase and L-alpha-amino-epsilon-caprolactam hydrolase is described. With the commercially available enzyme saccharopine dehydrogenase lysine formed either by decarboxylation of meso-diaminopimelate or by hydrolysis of L-alpha-amino-epsilon-caprolactam is converted to saccharopine with the concomitant oxidation of NADH, which is monitored by the decrease in absorbance at 340 nm. For meso-diaminopimelate decarboxylase this assay can be performed either as an endpoint determination, when working with crude extracts, or as a continuous spectrophotometric assay of partially purified enzyme preparations. The activity of L-alpha-amino-epsilon-caprolactam hydrolase can only be assayed by the endpoint method because of the great differences in the pH optima of the hydrolase and the saccharopine dehydrogenase.
authors.affiliation: Max-Planck-Institut für Biochemie, Abteilung Strukturforschung, Martinsried, Federal Republic of Germany.
authors.forename: B
authors.initials: B
authors.lastname: Laber
authors.forename: N
authors.initials: N
authors.lastname: Amrhein
mesh_terms: D001381:Azepines / Q000032:analysis*; D001426:Bacterial Proteins; D002209:Caprolactam / Q000032:analysis*; D002245:Carbon Dioxide / Q000032:analysis; D002262:Carboxy-Lyases / Q000032:analysis*; D008239:Lysine / Q000032:analysis / Q000031:analogs & derivatives; D009243:NAD / Q000032:analysis; D009555:Ninhydrin; D010084:Oxidation-Reduction; D012443:Saccharopine Dehydrogenases; D013056:Spectrophotometry, Ultraviolet
chemical_list: D001381:Azepines; D001426:Bacterial Proteins; D009243:NAD; D002245:Carbon Dioxide; D002209:Caprolactam; D012443:Saccharopine Dehydrogenases; C029496:saccharopine dehydrogenase (NADP+, lysine-forming); D002262:Carboxy-Lyases; C079912:LysA protein, Bacteria; C020031:diaminopimelic acid decarboxylase; D009555:Ninhydrin; D008239:Lysine; C100169:saccharopine