Purification and characterization of a neutral endoxylanase from Aspergillus nidulans

Abstract

A neutral endoxylanase from a culture filtrate of Aspergillus nidulans grown on oat spelt xylan was purified to apparent homogeneity. The purified enzyme showed a single band on SDS-PAGE with a molecular mass of 22,000 and had an isoelectric point of 6.4. The enzyme was a non-debranching endoxylanase highly specific for xylans and completely free from cellulolytic activity. The xylanase showed an optimum activity at pH 5.5 and 62°C and had a Km of 4.2 mg oat spelt xylan per ml and a Vmax of 710 μmol min-1 (mg protein)-1. © 1993.