Investigation of the functional relevance of the catalytically important Glu(28) in family 51 arabinosidases

Alpha-L-arabinofuranosidases: the potential applications in biotechnology

Recently, alpha-L-arabinofuranosidases (EC3.2.1.55) have received increased attention primarily due to their role in the degradation of lignocelluloses as well as their positive effect on the activity of other enzymes acting on lignocelluloses. As a result, these enzymes are used in many biotechnological applications including wine industry, clarification of fruit juices, digestion enhancement of animal feedstuffs and as a natural improver for bread. Moreover, these enzymes could be used to improve existing technologies and to develop new technologies. The production, mechanisms of action, classification, synergistic role, biochemical properties, substrate specificities, molecular biology and biotechnological applications of these enzymes have been reviewed in this article.

Synthesis of pentose-containing disaccharides using a thermostable α-l-arabinofuranosidase

To date, the enzymatically-catalysed synthesis of pentose-containing compounds has been limited to the production of oligo-beta-(1-->3) and oligo-beta-(1-->4)-linked xylopyranosides. To our knowledge, no such syntheses have involved arabinofuranose or, indeed, any other sugars in the furanose configuration. In this report, we describe the use of a thermostable alpha-L-arabinofuranosidase for the synthesis of p-nitrophenyl alpha-L-arabinofuranosyl-(1-->2)-alpha-L-arabinofuranoside, p-nitrophenyl beta-D-xylopyranosyl-(1-->2)-beta-D-xylopyranoside, p-nitrophenyl beta-D-xylopyranosyl-(1-->3)-beta-D-xylopyranoside and benzyl alpha-D-xylopyranosyl-(1-->2)-alpha-L-arabinofuranoside. Importantly, this latter compound is synthesised in a highly regiospecific reaction, which leads to the production of a single disaccharide.