Solving Biofuels’ Redox Equation

Abstract

For something so tiny and brainless, cyanobacteria have proven awfully hard to push around. The blue-green microbes are promising hosts for biofuel production. Yet attempts to boost output by engineering the microbes’ genomes rarely work in big bioreactors. Researchers at Pacific Northwest National Laboratory think setbacks happen because the biochemistry that regulates fuel compound production isn’t fully understood. At the American Chemical Society national meeting in San Francisco, they presented molecular probes that might help close that knowledge gap. The probes reveal metabolic pinch points regulated by oxidation and reduction of cysteine side chains on enzymes. Such reactions are commonplace and help cells respond to their environment, including the stresses of being coaxed to make biofuels. The probes covalently label reactive cysteine amino acids on proteins inside living cyanobacteria, but only when the cysteine thiol group is in its reduced form. “We want to identify proteins where redox chemi...