Supercomputing is being used to discover ways to make turning biomass into biofuel. The University of Tennessee and Oak Ridge National Laboratory (ORNL) project is led by Jeremy Smith, UT Governor’s Chair for Molecular Biophysics based in the Department of Biochemistry and Cellular and Molecular Biology. He also is director of the UT-ORNL Center for Molecular Biophysics.
A team at Oak Ridge National Laboratory (ORNL) performed its largest biological simulation to explain why lignin is so potent in blocking the enzymes that break down cellulose. Here, an enzyme (orange) hydrolyzes cellulose (green) despite the presence of lignin (brown). Image courtesy of ORNL/scistyle.com.
One of the biggest barriers to converting biomass, or plant matter, into biofuel lies in removing the other biomass polymers that inhibit this chemical process. To assist in finding a solution to this challenge, large-scale computational simulations are picking apart lignin, one of the problematic ploymers, and its interactions with cellulose and other plant compounds. The results should pave a path to more optimized biofuel production.
The research is also helping researchers better understand the complexity of plant cell walls.
Researchers at the UT-ORNL Center for Molecular Biophysics have been using supercomputers for many years to model and study lignin polymers and their interactions with cellulose. For this project, they’ve started to include other biomass polymers with the idea of simulating all the chemical components of plant cell walls. They’re now applying simulations again to the task: a hundred-million processor hours on Titan, ORNL’s Cray XK7 supercomputer.
To expand their simulations from cellulose polymers to lignin to ever more complicated biomolecule combinations, the team has had to optimize communication between parallel processors in supercomputers such as Titan. Smith says the machine’s capability should let them scale up to the point that the team can simulate atoms in parts of a plant’s cell wall. The team will begin by incorporating other cell wall biopolymers such as hemicelluloses and pectin and then add various enzymes and watch what happens – on the supercomputers that is.
“We can envisage simulations of the complete cell wall,” Smith says. Then they could expand to cell walls from a variety of plant species and even interactions between the plant cell walls and microbial surfaces. With exascale computing power – roughly 100 times that of Titan – Smith expects that the team might eventually simulate the workings of an entire plant cell.