Selig, Michael J.4; Thygesen, Lisbeth G.5; Felby, Claus5; Master, Emma R.3
1 Forest, Nature and Biomass, Department of Geosciences and Natural Resource Management, Faculty of Science, Københavns Universitet2 Forestry and wood products, Forest & Landscape Denmark, Faculty of Life Sciences, Københavns Universitet3 Department of Chemical Engineering and Applied Chemistry, University of Toronto,4 Forestry and wood products, Forest & Landscape Denmark, Faculty of Life Sciences, Københavns Universitet5 Forest, Nature and Biomass, Department of Geosciences and Natural Resource Management, Faculty of Science, Københavns Universitet
The presence of xylan is a detriment to the enzymatic saccharification of cellulose in lignocelluloses. The inhibition of the processive cellobiohydrolase Cel7A by soluble wheat arabinoxylan is shown here to increase by 50 % following enzymatic treatment with a commercially-purified α-l-arabinofuranosidase. The enhanced inhibitory effect was shown by T2 relaxation time measurements via low field NMR to coincide with an increasing degree of constraint put on the water in xylan solutions. Furthermore, quartz crystal micro-balance with dissipation experiments showed that α-l-arabinofuranosidase treatment considerably increased the rate and rigidity of arabinoxylan mass association with cellulose. These data also suggest significant xylan–xylan adlayer formation occurs following initial binding of debranched arabinoxylan. From this, we speculate the inhibitory effects of xylan to cellulases may result from reduced enzymatic access via the dense association of xylan with cellulose.
Biotechnology Letters, 2015, Vol 37, Issue 3, p. 633-641