Dr. Frances Arnold is a professor of Chemical Engineering and Biochemistry at the California Institute of Technology (most of us know it as Caltech). Dr. Arnold’s research focuses on evolutionary design of biological systems, an approach she is currently applying to engineer cellulases and cellulolytic enzymes for manufacturing biofuels.

This country’s energy security can look pretty bleak when you think about it: the need to address global warming, strife in oil-rich nations, and depletion of fossil fuels combine to paint an uncertain future, and although ethanol has a lot of friends in Iowa and D.C., ethanol isn’t going to end our energy woes. In the future, our energy supply will probably be cobbled together from a number of different fuels and sources. Dr. Arnold is interested in engineering microbes that can grant us a biofuel that packs more of a caloric punch than ethanol. She likes isobutanol, which can be converted into a fuel that’s more like the hydrocarbons we currently put into our fuel tanks. To develop proteins that make the comounds she wants the way she wants, Arnold and her team take a gene that needs tweaking to do the job, introduce directed mutations into it, and select the mutant proteins that do the job best. In this interview, I talked with Dr. Arnold about how she got into alternative energy during the Carter administration (and got out again during the Reagan administration), what she sees in the P450 enzyme, and how she explains her work to people outside her field.