Purification and characterization of isoforms of cinnamyl alcohol dehydrogenase from Eucalyptus xylem.

摘要: Two distinct isoforms of cinnamyl alcohol dehydrogenase, CAD 1 and 2, have been purified to homogeneity from xylem-enriched fractions ofEucalyptus gunii Hook partially characterized. They differ greatly in terms both physical biochemical properties, can be separated by hydrophobic interaction chromatography on Phenyl Sepharose CL-4B. The native molecular weight is 38 kDa as determined gel-filtration Superose 6, this isoform likely a monomer since it yields polypeptide 35 upon sodium dodecyl sulfatepolyacrylamide gel electrophoresis. It has low substrate affinity for coniferyl andp-coumaryl alcohols their corresponding aldehydes. No activity with sinapyl aldehyde was detected. more abundant which 83 dinier composed two subunits slightly different weights (42–43 kDa). These show identical peptide patterns after digestion N-chlorosuccinimide. isoform, high all the substrates tested. are immunologically polyclonal antibodies raised against 2 do not cross-react 1. characterization forms exhibiting such marked differences indicates involvement specific pathways monolignol utilisation.