Preparing a cyanobacterial chassis for H2 production: a synthetic biology approach
Molecular hydrogen (H2) is an environmentally clean energy carrier that can be a valuable alternative to the limited fossil fuel resources of today. The BioModularH2 project aims at designing reusable, standardized molecular building blocks that integrated into a “chassis” will result in a photosynthetic bacterium containing engineered chemical pathways for competitive, clean and sustainable hydrogen production. For this project the unicellular cyanobacterium Synechocystis sp. PCC 6803 (Synechocystis) is being used as the photoautotrophic “chassis” for this project. To prepare the chassis for an optimal H2 production, the Synechocystis native bidirectional hydrogenase was inactivated. Later on, a synthetic circuit containing a heterologous highly efficient hydrogenase will be introduced into the “chassis”. Due to hydrogenase sensitivity to molecular oxygen, and to provide the anaerobic environment required for an optimal heterologous hydrogenase activity, synthetic oxygen consuming devices are being prepared based on native and heterologous enzymes that use O2 as substrate, and will be subsequently tested. Finally, the integration of the designed synthetic circuits into the “chassis” will provide an anaerobic environment within the cell for an optimized and highly active hydrogenase.