Lytic enzymes of Trichoderma and their role in protecting plants from fungal diseases

Lytic enzymes of mycoparasitic fungi of the genus Trichoderma, capable of suppressing several fungal phytopathogens that originate in air or soil, are reviewed. The topics analyzed include (1) regulation of production of chitinases, beta-1,3-glucanases, and proteases; (2) molecular and catalytic properties of purified enzymes; and (3) their in vitro ability to degrade cell walls and inhibit sporulation or germ-tube elongation in various phytopathogenic fungi. Among the results summarized are reports of cloning the expression of genes coding for certain lytic enzymes of Trichoderma spp. These genes are used for obtaining plant transgenes with increased resistance to fungal diseases and Trichoderma transformants that produce higher levels of one lytic enzyme (a chitinase or protease) and thereby exhibit a more pronounced ability to suppress phytopathogenic fungi.