PURIFICATION OF SUCROSE SYNTHASE FROM RICE AND ITS PROTEIN-CHEMICAL CHARACTERIZATION

Sucrose synthase from rice grains was purified using anion exchange techniques and preparative gel filtration. In order to utilize the enzyme in subsequent enzymatic syntheses of nucleotide sugars the purification protocol was optimized to yield an enzyme preparation which is free of phosphatases hydrolysing nucleotides. The enzyme preparation was investigated by SDS polyacrylamide gel-electrophoresis (molecular mass of subunit 90 kDa) and isoelectric focusing (pI 6.16) with silver staining. The native enzyme is a tetrameric protein with a molecular mass of 362 kDa. Edman degradation revealed a blocked N-terminus.