title: On the specificity and mode of action of a xylanase from Trametes hirsuta (Wulf.) Pilát.
abstract: The mode of action of the extracellular endo-(1 leads to 4)-beta-D-xylanase produced by Trametes hirsuta on a (4-0-methyl-D-glucurono)-D-xylan and a modified, essentially neutral D-xylan from white willow (Salix alba L.) has been studied. Xylotetraose and xylohexaose, together with aldotetraouronic and aldohexaouronic acids, were the main products. The acidic oligosaccharides had a 4-O-methyl-D-glucopyranosyluronic acid group attached to the non-reducing D-xylosyl end-group. The action pattern of the xylanase corresponds to that of a typical endo-enzyme that acts more readily in the middle of chain, and the specific region of its action appears to involve five D-xylosyl residues. The products of the enzymic treatment of the D-xylan have revealed a regular distribution of the 4-O-methyl-D-glucopyranosyluronic acid groups attached to the D-xylan backbone.
mesh_terms: D001487:Basidiomycota / Q000201:enzymology*; D006026:Glycoside Hydrolases / Q000378:metabolism*; D007700:Kinetics; D009844:Oligosaccharides; D010944:Plants; D011124:Polyporaceae / Q000201:enzymology*; D013045:Species Specificity; D014197:Trees; D014990:Xylans
chemical_list: D009844:Oligosaccharides; D014990:Xylans; D006026:Glycoside Hydrolases