Temperature-sensitive PSII and promiscuous PSI as a possible solution for sustainable photosynthetic hydrogen production.

Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
Biochimica et Biophysica Acta (Impact Factor: 4.66). 01/2012; 1817(8):1122-6. DOI: 10.1016/j.bbabio.2012.01.005
Source: PubMed

ABSTRACT Sustainable hydrogen production in cyanobacteria becomes feasible as a result of our recent studies of the structure of photosystem I encoding operon in a marine phage. We demonstrated that the fused PsaJF subunit from the phage, substituted for the two separate subunits in Synechocystis, enabled the mutated PSI to accept electrons from additional electron donors such as respiratory cytochromes. In this way, a type of photorespiration was created in which the cell consumes organic material through respiratory processes and PSI serves as a terminal electron acceptor, substituting for cytochrome oxidase. We designed a hydrogen-producing bioreactor in which this type of photorespiration could utilize the organic material of the cell as an electron source for H(2) production. We propose, in parallel, to engineer cyanobacterial and/or algal strains with a temperature-sensitive PSII and enhanced respiration rates to achieve efficient and sustainable hydrogen production. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: from Natural to Artificial.

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