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Title: Rewiring photosynthesis: a photosystem I-hydrogenase chimera that makes H 2 in vivo
Harnessing the power of photosynthesis to catalyze novel light-driven redox chemistry requires a way to intercept electron flow directly from the photosynthetic electron transport chain (PETC). As a proof of concept, an in vivo fusion of photosystem I (PSI) and algal hydrogenase was created by insertion of the HydA sequence into the PsaC subunit. The PSI and hydrogenase portions are co-assembled and active in vivo , effectively creating a new photosystem. Cells expressing only the PSI-hydrogenase chimera make hydrogen at high rates in a light-dependent fashion for several days. In these engineered cells, photosynthetic electron flow is directed away from CO 2 fixation and towards proton reduction, demonstrating the possibility of driving novel redox chemistries using electrons from water splitting and the photosynthetic electron transport chain.  more » « less
Award ID(s):
1706960
PAR ID:
10169112
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Energy & Environmental Science
ISSN:
1754-5692
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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