ENZYMES OF WHITE-ROT FUNGI INVOLVED IN LIGNIN DEGRADATION AND ECOLOGICAL DETERMINANTS FOR WOOD DECAY

White-rot fungi preferably degrade wood from deciduous trees, whilst w ood decay by brown-rot fungi is predominant on coniferous substrates. A compilation of recent publications on ligninolytic fungal species an d their substrate preference is presented. These organisms can be clas sified on the basis of their enzyme systems, but an unambiguous alloca tion to specific hosts proved to be difficult. Environmental condition s may be crucial in governing the selectivity of fungal biodegradation of wood components. Possible mechanisms of primary attack of the wood cell wall by hemicellulose degradation are discussed. Furthermore, a hypothetical scheme for lignin biodegradation involving oxidative clea vage of phenolic, C-alpha-oxo-substituted substructures is presented.