Role of O-methyltransferase in the lignification of Douglas-fir cultured tissue

Thesis/Dissertation · Sat Jan 01 04:00:00 EST 1983

OSTI ID:5527405

Monroe, S H

O-methyltransferase (OMT) is a key enzyme in the biosynthesis of lignin. This enzyme was isolated and characterized in an effort to understand why Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) callus tissue does not form appreciable amounts of lignin yet does form large amounts of the related flavonoids and tannins. It was shown that the OMT in the callus tissue is a cell wall associated, membrane-bound enzyme, in contrast to that of all reported plant species and to Douglas-fir seedlings, which have either a microsomal or soluble OMT. The effect this had on the OMT kinetic constants was studied. It was found that the callus OMT had much higher K/sub m/ constants for caffeic acid in both the membrane-bound and free forms compared with seedlings. The callus membrane-bound K/sub m/ for caffeic acid is 333 ..mu..M. The callus membrane-free K/sub m/ for caffeic acid is 250 ..mu..M. The seedling K/sub m/ for caffeic acid is 90 ..mu..M.

• Research Organization: Institute of Paper Chemistry, Appleton, WI (USA)
• OSTI ID: 5527405
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
550200 -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
CARBOHYDRATES
CHEMICAL PROPERTIES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DATA
ENZYMES
EXPERIMENTAL DATA
FIRS
INFORMATION
KINETICS
LIGNIN
METHYL TRANSFERASES
NUMERICAL DATA
ORGANIC COMPOUNDS
PLANTS
POLYSACCHARIDES
REACTION KINETICS
SACCHARIDES
TRANSFERASES
TREES