Identification of adaptive evolutionary changes in Trichoderma chitinase chi18-13

Abstract: Mycoparasitic fungi such as Trichoderma are used as biological control agents againstfungal pathogens on agricultural crops. Chitinases are hydrolytic enzymes that degrade fungalcell walls and are important for the mycoparasitic attack. We here analyse the molecularevolution of Trichoderma chitinase chi18-13, and show that changes in enzyme architecture arepreferentially localized to substrate- or product side of the catalytic cleft. These observationssuggest that mycoparasitic interactions can drive adaptive changes of enzymes. The approach canbe used to identify factors that are important for microbial interactions and to reveal relationshipsbetween enzyme structure and function.