Chitotriosidase-1 (CHIT1), a member of the glycosyl hydrolase 18 family and Chitinase class II subfamily, is also known as Chitinase-1, which contains one chitin-binding type-2 domain. As the digestive enzymes, Chitinases can break down glycosidic bonds in chitin. The chitin-binding type-2 domain of CHIT1 is able to degrade chitin and chitotriose. Chitin, like cellulose, has been thought of as abundant but difficult to digest. Furthermore, CHIT1 may participate in the defense against nematodes and other pathogens.