Polymerization of monolignols by redox shuttle-mediated enzymatic oxidation: a new model in lignin biosynthesis I

Lignin is one of the most abundant biopolymers, and it has a complex racemic structure. It may be formed by a radical polymerization initiated by redox enzymes, but much remains unknown about the process, such as how molecules as large as enzymes can generate the compact structure of the lignified plant cell wall. We have synthesized lignin oligo-mers according to a new concept, in which peroxidase is never in direct contact with the lignin monomers coniferalde-hyde and coniferyl alcohol. Instead, manganese oxalate worked as a diffusible redox shuttle, first being oxidized fro