An endogalactosaminidase from Streptomyces griseus.
An endogalactosaminidase has been purified 34-fold from the culture filtrate of Streptomyces griseus. This enzyme cleaves GalN-GalN linkages in oligogalactosaminoglycan, a galactosamine-rich oligosaccharide isolated from the culture filtrate of a Neurospora mutant. Since some or all of the GalN-GalN bonds in this molecule link positions 1 and 4, and are in the alpha-configuration, we are probably dealing with an endo-alpha-(1 leads to 4)-galactosaminidase, bu this characterization is only tentative because the few bonds cleaved by the enzyme could have a different structure. The enzyme is inactive towards N-acetyl-oligogalactosaminoglycan and chitosan. The endogalactosaminidase preparations also cleave high molecular weight galactosaminoglycan (obtained from Neurospora) into fragments greater than or equal to 10(4) daltons in molecular weight, and catalyze the release of Neurospora sporelings from the glass surfaces to which they are anchored. Galactosaminoglycan-cleaving and sporeling-releasing activities elute jointly from DEAE-cellulose columns. This observation provides further support for an earlier proposal that the sporelings are anchored to the glass by means of galactosaminoglycan molecules.
D006025:Glycosaminoglycans; D006596:Hexosaminidases / Q000302:isolation & purification / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009492:Neurospora crassa; D013045:Species Specificity; D013305:Streptomyces griseus / Q000201:enzymology*; D013329:Structure-Activity Relationship
D006025:Glycosaminoglycans; D006596:Hexosaminidases