Abstract
Lignin, a macromolecular polymer of monolignols, is accumulated in secondary cell walls of vascular tissues, engaging in the mechanical support. Lignification also takes place in response to wounding and pathogen attack for biogenic defense. Monolignols are polymerized into lignin by peroxidases by using hydrogen peroxide.
In this study, we attempted to reduce lignin contents by reducing hydrogen peroxide in plants. For the purpose, we used two extracellular catalases, Botrytis cinerea BcCAT2 and Arabidopsis AtCAT2 added the signal peptide of Zinnia peroxidase ZPO-C. The constructs of these catalse genes were introduced into the tobacco BY-2 cultured cells and Arabidopsis using Agrobacterium method. These catalses were tagged with GFP or 6xHis at the C-terminus and expressed by the CaMV 35S promoter. We will report the enzymatic characterization of the recombinant catalses expressed in tobacco cultured cells and the effects of the expressions of recombinant catalases in Arabidopsis plants.
