title: Design of new strategy for green algal photo-hydrogen production: spectral-selective photosystem I activation and photosystem II deactivation.
abstract: A new strategy in photosynthetic hydrogen (photo-H(2)) production from green algae was developed based on theory and successfully demonstrated. The new strategy applied a spectral-selective photosystem I (PSI) activating/photosystem II (PSII) deactivating radiation (or PSI light) that would drive a steady flow of electrons in the electron transport chain for delivery to hydrogenase for photo-H(2) production, but would reduce oxygen production through water photolysis below the respiratory oxygen consumption so that an anoxic condition would be maintained as required by hydrogenase. Implementing the strategy by using a PSI light (692 nm peak, 680-700 nm) on Chlamydomonas reinhardtii cells resulted in relatively sustained photo-H(2) production (total of 0.108 mL H(2)mg(-1)Chl, exceeding 0.066 mL H(2)mg(-1)Chl under white light). The strategy also proved successful and convenient in allowing cells to alternately switch between photo-H(2) production and a recovery period by simply turning on or off the PSI light.
authors: Department of Agricultural and Biosystems Engineering, The University of Arizona, Tucson, AZ 85721, USA. takanori@email.arizona.edu
authors: Takanori
authors: T
authors: Hoshino
authors: Daniel J
authors: DJ
authors: Johnson
authors: Joel L
authors: JL
authors: Cuello
mesh_terms: D016825:Chlamydomonas reinhardtii / Q000378:metabolism; D004789:Enzyme Activation; D006859:Hydrogen / Q000378:metabolism*; D008027:Light; D009154:Mutation / Q000235:genetics; D055668:Photochemical Processes / Q000528:radiation effects; D010777:Photochemistry / Q000379:methods*; D045331:Photosystem I Protein Complex / Q000378:metabolism*; D045332:Photosystem II Protein Complex / Q000378:metabolism*; D013057:Spectrum Analysis; D013816:Thermodynamics; D013997:Time Factors
chemical_list: D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D006859:Hydrogen