Purification and characterization of succinyl-CoA: tetrahydrodipicolinate N-succinyltransferase from Escherichia coli.
Tetrahydrodipicolinate succinylase, an enzyme involved in the diaminopimelate-lysine pathway, was purified 1900-fold from crude extracts of Escherichia coli. The enzyme catalyzes the formation of CoA and N-succinyl-2-amino-6-keto-L-pimelate from succinyl-CoA and tetrahydrodipicolinate. The purified enzyme was shown to be homogeneous by polyacrylamide gel electrophoresis. The Stokes radius of the enzyme was determined from its elution volume on a Sephacryl S300 column and its sedimentation constant from sucrose density gradient centrifugation. These were 35 A and 4.7 (S20,w), respectively. The enzyme consists of two subunits each with a mass of 31,000 daltons, as determined using sodium dodecyl sulfate/polyacrylamide gel electrophoresis. Tetrahydrodipicolinate succinylase was shown to be a sulfhydryl enzyme. It has a pH optimum of 8.2. The equilibrium lies predominantly in favor of product formation but the reverse reaction can be demonstrated in vitro.
D000217:Acyltransferases / Q000302:isolation & purification* / Q000378:metabolism; D002250:Carbon Radioisotopes; D002413:Cations, Divalent; D004926:Escherichia coli / Q000201:enzymology*; D007700:Kinetics; D008970:Molecular Weight; D013439:Sulfhydryl Reagents / Q000494:pharmacology
D002250:Carbon Radioisotopes; D002413:Cations, Divalent; D013439:Sulfhydryl Reagents; D000217:Acyltransferases; C040777:succinyl-CoA-tetrahydrodipicolinate N-succinyltransferase