Genetic manipulation of lignin reduces recalcitrance and improves ethanol production from switchgrass

Switchgrass is a leading dedicated bioenergy feedstock in the United States because it is a native, high-yielding, perennial prairie grass with a broad cultivation range and low agronomic input requirements. Biomass conversion research has developed processes for production of ethanol and other biofuels, but they remain costly primarily because of the intrinsic recalcitrance of biomass. We show here that genetic modification of switchgrass can produce phenotypically normal plants that have reduced thermal-chemical (≤180 °C), enzymatic, and microbial recalcitrance. Down-regulation of the switchgrass caffeic acid O-methyltransferase gene decreases lignin content modestly, reduces the syringyl:guaiacyl lignin…

• UD
  U.S. Department of Energy

  Awards: AC05-00OR22725, under Contract DE-AC05-00OR22725, DE-AC05, 00OR22725
• UD
  U.S. Department of Agriculture
• SR
  Samuel Roberts Noble Foundation
• B
  Battelle

  Awards: DE-AC05, DE-AC05-00OR22725
• U
  UT-Battelle

  Awards: Contract DE-AC05-00OR22725, DE-AC05-, AC05-00OR22725
• OO
  Office of Science

  Awards: DE-AC05-00OR22725, AC05-00OR22725
• BA
  Biological and Environmental Research

  Awards: DE-AC05-00OR22725, 00OR22725
• OR
  Oak Ridge National Laboratory

  Award: AC05-00OR22725