Enzymes and small molecular mass agents involved with lignocellulose degradation

Electron microscopic and biochemical studies of lignocellulose degradation by wood-rotting fungi have shown that enzymes such as lignin peroxidases, manganese-dependent peroxidases, laccases and cellulases are too large to penetrate undegraded secondary wood cell walls.Degradation occurs by surface interaction between cell wall and enzymes, but initiation of decay at a distance from the fungal hyphae must involve diffusible low-molecular mass agents.The roles of hydrogen peroxide, veratryl alcohol, oxalate, Fe2+-Fe 3+ and Mn2+-Mn 3+, as such agents in lignocellulose degradation are discussed.