Dermatan sulfate epimerase 1 and dermatan 4-O-sulfotransferase 1 form complexes that generate long epimerized 4-O-sulfated blocks
During the biosynthesis of chondroitin/dermatan sulfate (CS/ DS), a variable fraction of glucuronic acid is converted to iduronic acid through the activities of two epimerases, dermatan sulfate epimerases 1 (DS-epi1) and 2 (DS-epi2). Previous in vitro studies indicated that without association with other enzymes, DS-epi1 activity produces structures that have only a few adjacent iduronic acid unit