P70: Biodiesel from cyanobacteria

Recent interests have focused on the development of algae (green algae and cyanobacteria, aka blue-green algae) as sources of renewable biofuels.  A model organism is needed to study carbon metabolism and regulation, in order to redirect carbon flow to fuel production.  The cyanobacterium Synechocystis sp. PCC 6803 is a genetic model well suited for systems biology research and metabolic engineering.  While the wild-type strain does not accumulate triacylglycerol (TAG), the feedstock of biodiesel, it can accumulate high levels of carbon storage compounds such as glycogen (up to 55% cell dry weight).  By redirecting the carbon storage pathway away from normal carbon storage compounds and towards the accumulation of lipids, Synechocystis could be an ideal system for solar biofuel research and production.  By selectively mutating the agp gene, essential to glycogen biosynthetic pathway, we have removed an undesired carbon sink.  We are engineering Synechocystis by introducing the fatty acid carbon storage pathway.  The goal is to generate strains that are capable of accumulating biodiesel.