Plant Biology Seminar

Building and Enhancing Multispecies Microbial Consortia Driven by Light

We are engineering a synthetic, microbial consortia platform for
light-driven production of a flexible array of fuels and chemicals. The
basis of this approach is a cyanobacterial strain (*Synechococcus elongatus*
PCC 7942) that has been modified to secrete sucrose in sufficient
quantities to fulfill the carbohydrate requirements for co-cultivated
heterotrophic microbes. Therefore, the cyanobacteria act as the
photosynthetic module within the consortia, while the supported
heterotrophs directly consume the feedstock – reducing processing and
transport costs. We will discuss how sucrose secretion changes parameters
of cyanobacterial photosynthesis, including how this heterologous
production may improve the quantum efficiency of light harvesting by
relaxing "sink inhibition." Furthermore, we'll discuss parallel approaches
involving rational engineering, forward genetics, and directed evolution to
increase the productivity of co-cultures.