the lack of detectable levels of ( 1 ) glucosamine in cyst wall hydrolysates , ( 2 ) cyst staining by calcofluor m2r , ( 3 ) endogenous chitinase activity and ( 4 ) n-acetylglucosamine when cysts served as a substrate for exogenous chitinase suggests that the giardia cyst wall is not composed largely of chitin as previously reported . beta-n-acetylgalactosaminidase , ec 3.2.1.32 , activity was detected in cysts and trophozoites and represents the first carbohydrate splitting hydrolase detected in giardia .
C0017718
glucosamine
C0001056
n-acetylglucosamine