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


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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Available from: Nathan Nelson, Dec 09, 2014
    • "In C. reinhardtii, activation of [FeFe]-hydrogenase isoform1 (HYDA1) is believed to function as an electron valve and control the chloroplast redox poise under oxygen deficiency (Grossman et al., 2011; Hemschemeier and Happe, 2011). As outlined by Mazor et al. (2012), protons could have served as a sink for excess electrons produced by photosynthesis , when oxygenic photosynthesis suffered a shortage of oxidized electron acceptors in early-earth reductive atmosphere. Thus, hydrogenase might have evolved to sustain ATP production by LEF under an anoxic atmosphere, implicating that oxygen produced by PSII is readily consumed by respiration. "
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    • "One of the most promising current bio-photovoltaic without using elaborate or expensive surface chemistries is a PSI complex attached to a semiconductor, achieving a photocurrent density of 362 µA/cm2 and 0.5 V [15]. Purified complexes [20], photosynthetic membranes [21-24] or whole organisms [25-29] have also been placed on electrodes for assembling biosensors (for review see [30, 31]), mainly for the detection of pollutants, but also as components for future H2 production devices [32]. As PSI has a higher efficiency and is less prone to photoinhibion than PSII (see later), it could be more suitable for biomimetic devices (for recent reviews see [32-34]). "
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