Trophic obligate conversion of an photoautotrophic organism through metabolic engineering

Most microalgae are obligate photoautotrophs and their growth is strictly d ependent on the generation of photosynthetically derived energy. We show th at the microalga Phaeodactylum tricornutum can be genetically engineered to thrive on exogenous glucose in the absence of light through the introducti on of a gene encoding a glucose transporter (glut1 or hup1). This demonstra tes that a fundamental change in the metabolism of an organism can be accom plished through the introduction of a single gene. This also represents pro gress toward the use of fermentation technology for large-scale commercial exploitation of algae by reducing limitations associated with light-depende nt growth.