Photosynthetic Chassis Choice
the 2 strains of bacteria he is using: Synechoccus elongatus and Synechocystis elongatus. The genomes have been sequenced, transformations are easy, and one of they grows solely on sunlight, co2 and seawater, whereas the other one needs some sugars. Dave has developed the new BioBrick fragment for the ~30 kb section of DNA he was working on to not contain any restriction sites. I think the only problem he has encountered is that the organism is 65% GC rich, making sequencing impossible and PCR's difficult.
One or both of these organisms would be a really good starting point. if you can get H2, O2 and a source of food from 1 organism. This screams to me as being something we need. It makes fatty acids and can generate a lot of biomass as it fixes its own carbon and nitrogen. Which means there may be a way to make grease or oil as well. Jason has looked into this organism in more detail and can fill you in with the more detailed biology.