November 23, 2012
Nanoscale Architecture of Plant Cell Walls Determines Their Accessibility and Digestibility by Enzymes
Plant cell walls are complex nanocomposites containing networks of cellulose fibrils and complex “matrixing” polymers. There is little agreement about which plant cell wall features most affect digestibility by microbes and cellulolytic enzymes. The overall performance of biomass saccharification may be attributed to the synergistic action of many complementary enzymes, which makes it difficult to study one factor at a time. Traditional solution methods have suffered from the classical ensemble average limitation presented by analysis of these mixtures of complex biomass, and the bulk data measurements gathered are therefore sometimes inconclusive and in part contradictory. Our imaging data support the hypothesis that ideal pretreatments should maximize lignin removal and minimize polysaccharide modification, thereby retaining the essentially native microfibrillar structure and improving accessibility.