Characterization of the last step of lignin biosynthesis in Zinnia elegans suspension cell cultures.
The last step of lignin biosynthesis in Zinnia elegans suspension cell cultures (SCCs) catalyzed by peroxidase (ZePrx) has been characterized. The k(3) values shown by ZePrx for the three monolignols revealed that sinapyl alcohol was the best substrate, and were proportional to their oxido/reduction potentials, signifying that these reactions are driven exclusively by redox thermodynamic forces. Feeding experiments demonstrate that cell wall lignification in SCCs is controlled by the rate of supply of H(2)O(2). The results also showed that sites for monolignol beta-O-4 cross-coupling in cell walls may be saturated, suggesting that the growth of the lineal lignin macromolecule is not infinite.
Gabaldón
Carlos
C
Department of Plant Biology, University of Murcia, E-30100 Murcia, Spain.
López-Serrano
Matías
M
Pomar
Federico
F
Merino
Fuencisla
F
Cuello
Juan
J
Pedreño
M A
MA
Barceló
A Ros
AR
D019659:Asteraceae / Q000166:cytology / Q000201:enzymology*; D002478:Cells, Cultured; D008031:Lignin / Q000096:biosynthesis*; D009195:Peroxidase / Q000737:chemistry* / Q000378:metabolism; D010666:Phenylpropionates / Q000737:chemistry / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry* / Q000378:metabolism
D010666:Phenylpropionates; D010940:Plant Proteins; C496130:sinapyl alcohol; D008031:Lignin; D009195:Peroxidase