Degradation process of hyaluronic acid by Streptomyces hyaluronidase

Saturated and unsaturated hyaluronate oligosaccharides were prepared from human umbilical cord hyaluronic acid by partial digestion with bovine testicular and Streptomyces hyaluronidase, respectively. After treatment with Streptomyces hyaluronidase, the distribution of degradation products from these oligosaccharides was determined. Octasaccharides, either saturated or unsaturated, were substrates of the minimum size. Tetra- and hexasaccharides were not degraded further and remained as final products. This indicates that at least four succeeding N-acetylhyalobiuronosyl residues were required for this enzymatic degradation. Since unsaturated oligosaccharides were more susceptible to this enzyme than saturated ones of the same polymerization degree, and inner glucosaminidic linkages were cleaved in preference to those at the outermost sites, some groups adjacent to this segment seemed to influence the susceptibility of the oligosaccharide to this enzyme.