Findings from Aix-Marseille University Yields New Findings on Hydrogen [Plastidial Expression of Type II NAD(P)H Dehydrogenase Increases the Reducing State of Plastoquinones and Hydrogen Photoproduction Rate by the Indirect Pathway in ...]
By a News Reporter-Staff News Editor at Life Science Weekly -- New research on Hydrogen is the subject of a report. According to news reporting out of Marseille, France, by NewsRx editors, research stated, "Biological conversion of solar energy into hydrogen is naturally realized by some microalgae species due to a coupling between the photosynthetic electron transport chain and a plastidial hydrogenase. While promising for the production of clean and sustainable hydrogen, this process requires improvement to be economically viable."
Our news journalists obtained a quote from the research from Aix-Marseille University, "Two pathways, called direct and indirect photoproduction, lead to sustained hydrogen production in sulfur-deprived Chlamydomonas reinhardtii cultures. The indirect pathway allows an efficient time-based separation of O-2 and H-2 production, thus overcoming the O-2 sensitivity of the hydrogenase, but its activity is low. With the aim of identifying the limiting step of hydrogen production, we succeeded in overexpressing the plastidial type II NAD(P) H dehydrogenase (NDA2). We report that transplastomic strains overexpressing NDA2 show an increased activity of nonphotochemical reduction of plastoquinones (PQs). While hydrogen production by the direct pathway, involving the linear electron flow from photosystem II to photosystem I, was not affected by NDA2 overexpression, the rate of hydrogen production by the indirect pathway was increased in conditions, such as nutrient limitation, where soluble electron donors are not limiting. An increased intracellular starch was observed in response to nutrient deprivation in strains overexpressing NDA2. It is concluded that activity of the indirect pathway is limited by the nonphotochemical reduction of PQs, either by the pool size of soluble electron donors or by the PQ-reducing activity of NDA2 in nutrient-limited conditions."
According to the news editors, the research concluded: "We discuss these data in relation to limitations and biotechnological improvement of hydrogen photoproduction in microalgae."
For more information on this research see: Plastidial Expression of Type II NAD(P)H Dehydrogenase Increases the Reducing State of Plastoquinones and Hydrogen Photoproduction Rate by the Indirect Pathway in Chlamydomonas reinhardtii. Plant Physiology, 2014;165(3):1344-1352. Plant Physiology can be contacted at: Amer Soc Plant Biologists, 15501 Monona Drive, Rockville, MD 20855, USA. (Elsevier - www.elsevier.com; Plant Physiology - www.elsevier.com/wps/product/cws_home/600784)
Our news journalists report that additional information may be obtained by contacting A. Baltz, Aix Marseille Univ, Unit Mixte Rech Biol Vegetale & Microbiol Environ, F-13284 Marseille, France. Additional authors for this research include K.V. Dang, A. Beyly, P. Auroy, P. Richaud, L. Cournac and G. Peltier (see also Hydrogen).
Keywords for this news article include: NAD, Gases, France, Europe, Elements, Marseille, Benzoquinones, Dehydrogenase, Plastoquinone, Inorganic Chemicals, Enzymes and Coenzymes
Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC