TABLE 1.

Representative members of the conserved family of 18 glycosyl hydrolases

	Name	Enzymic activity	Position of domain
CHIT1	Chitotriosidase Chitinase 1	Hydrolytic and trans-glycosylation activity	Glyco-18 domain (22–363) Chitin-binding domain (418–466) Catalytic site (136–140)
CHIA	AMCase Eosinophil chemotactic cytokine	Hydrolytic activity	Glyco-18 domain (1–257) Chitin-binding domain (321–368) Catalytic site (136–140)
CHI3L1	YKL-40/BRP-39 Cartilage glycoprotein 1 GP-39 HcGP-39	No	Glyco-18 domain (22–360)
CHI3L2	YIL-39 Chondrocyte protein 39	No	Glyco-18 domain (22–357)
CHI3L3	Ym1	No	Glyco-18 domain (22–365)
CHI3L4	Ym2	No	Glyco-18 domain (22–365)

AMCase: acidic mammalian chitinase.