Photosynthetic hydrogen production

Abstract

A process for the production of hydrogen, comprising the steps of: (i) providing a photosynthetic microorganism having electron transfer capability through a photosynthetic “light” reaction pathway and through a respiratory electron transfer chain involving an oxidative phosphorylation pathway, and which expresses a hydrogenase, wherein regulation of the oxidative phosphorylation pathway is disrupted with the result that electron flow along the respiratory electron transfer chain toward cytochrome oxidase (complex IV) is reduced; ii) culturing the microorganism under microoxic and illuminated conditions; and (iii) collecting evolved hydrogen.

1 - 29 . (canceled) 
     
     
         30 . A process for the production of hydrogen, comprising the steps of:
 (i) culturing a photosynthetic green alga from the family Chlamydomondaceae which expresses a chloroplast hydrogenase, wherein oxidative phosphorylation is disrupted with the result that cyclic electron transport in the chloroplast is reduced, inhibited or suppressed and linear electron transport to the hydrogenase is increased or augmented, under microoxic and illuminated conditions; and   (ii) collecting evolved hydrogen.   
     
     
         31 . A process as claimed in  claim 30 , wherein the green alga is cultured under micromolar sulphur conditions. 
     
     
         32 . A process as claimed in  claim 30 , wherein oxidative phosphorylation is disrupted through modulation of the activity of the mitochondrial transcription factor Moc1. 
     
     
         33 . A process as claimed in  claim 30 , wherein the activity of Moc1 is inhibited, suppressed or otherwise reduced. 
     
     
         34 . A process as claimed in  claim 30  wherein Moc1 is subjected to antisense inhibition. 
     
     
         35 . A process as claimed in  claim 30  wherein Moc1 is silenced by RNAi. 
     
     
         36 . A process as claimed in  claim 33 , wherein an inactivating genomic mutation reduces or eliminates Moc1 activity. 
     
     
         37 . A process as claimed in  claim 30 , wherein hydrogen production is increased through the addition of an ATP synthase uncoupler to the photosynthetic electron transport chain. 
     
     
         38 . A process as claimed in  claim 37  wherein the uncoupler is selected from the group consisting of Carbonyl cyanide 3-chloro-phenylhydrazone (CCCP); 1,3-Dicyclo-hexylcarbodiimide (DCC); Ammonium chloride; Venturicidin; carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP); 2,4-dinitrophenol; Gramicidin and Nigericin. 
     
     
         39 . A process as claimed in  claim 30 , wherein atmospheric carbon dioxide is consumed by the green alga during culture. 
     
     
         40 . A process as claimed in  claim 30  wherein the green alga is from the genus  Chlamydomonas.    
     
     
         41 . A process as claimed in  claim 40 , wherein the green alga is  Chlamydomonas reinhardtii.