PURIFICATION AND CHARACTERIZATION OF SUCCINYL-COA - TETRAHYDRODIPICOLINATE N-SUCCINYLTRANSFERASE FROM ESCHERICHIA-COLI

  • 1 January 1984
    • journal article
    • research article
    • Vol. 259  (5) , 2734-2741
Abstract
Tetrahydrodipicolinate succinylase, an enzyme involved in the diaminopimelate-lysine pathway, was purified 1900-fold from crude extracts of E. 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 .ANG. and 4.7 (s20,w), respectively. The enzyme consists of 2 subunits each with a mass of 31,000 dalltons, as determined using sodium dodecyl sulfate/polyacrylamide gel electrophoresis. Tetrahydrodipicolinate succinylase is a SH 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.