1.13.11.60 glycoprotein 7,8-LDS contains five tentative N-linked glycosylation sites, one of which has high probability of glycosylation. This N-glycosylation site, Asn216, is located near the distal heme-binding region along with tentative sites for O-linked glycosylation. Asn216Gln shows no detectable enzyme activity, although expression of Asn216Gln is confirmed by Western blot analysis. alpha-Mannosidase treatment does not change the 8R-dioxygenase activity but abolishes the hydroperoxide isomerase activity. Proper N- and O-linked glycosylation could be important for the hydroperoxide isomerase. Expression of 7,8-LDS in insect cells yields recombinant 7,8-LDS with the native hydroperoxide isomerase activity -, 702018