Abstract
At the initial stage of cellular degradation of chondroitin sulfate/dermatan sulfate, an endo-type hydrolase is thought to degrade the long chain polysaccharides. Thus far, no endoglycosidases that are specific for chondroitin sulfate/dermatan sulfate have been reported; however, hyaluronan-degrading enzymes, hyaluronidases, are considered responsible. The nematode, Caenorhabditis elegans, is an ideal model for studies in a wide range of fundamental biological disciplines. Studies using the nematode have elucidated the biosynthetic mechanisms and functions of glycosaminoglycans. However, the catabolic pathways for glycosaminoglycans in C. elegans have not been investigated. Since C. elegans contains nonsulfated chondroitin but no hyaluronan, it is an ideal system for studying the hyaluronidase-independent catabolic mechanism of chondroitin/chondroitin sulfate. We have identified a chondroitin-specific endo-type hydrolase in C. elegans for the first time. The discovery of this enzyme suggests the presence of chondroitin sulfate/dermatan sulfate-specific endoglycosidases in mammalian systems.
