It's the unofficial start of summer today in the US and that usually means drivers face higher gas prices. If one synthetic biology company has its way, butanol may someday be making its way into gas tanks all over the country, reports the Nature News blog. Gevo has established a factory in Minnesota that the company says will be producing 1 million gallons of isobutanol a month by the end of the year. Nature notes that Gevo uses technology based on work by the University of California, Los Angeles' James Liao that uses yeast cells with re-engineered metabolic pathways that make isobutanol rather than amino acids. Other companies, including Butaman and Green Biologics, are also focused on turning forms of butanol into a biofuel.