[1] Univ Calif San Francisco, Dept Bioengn & Therapeut Sci, San Francisco, CA 94158 USA
[2] Joint BioEnergy Inst, Div Technol, Emeryville, CA 94608 USA
[3] Sandia Natl Labs, Biomass Sci & Convers Technol Dept, Livermore, CA 94551 USA
[4] Yale Univ, Dept Mol Biophys & Biochem, New Haven, CT 06511 USA