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Mechanistic modeling of sulfur-deprived photosynthesis and hydrogen production in suspensions of Chlamydomonas reinhardtii

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      The ability of unicellular green algal species such as Chlamydomonas reinhardtii to produce hydrogen gas via iron-hydrogenase is well known. However, the oxygen-sensitive hydrogenase is closely linked to the photosynthetic chain in such a way that hydrogen and oxygen production need to be separated temporally for sustained photo-production. Under illumination, sulfur-deprivation has been shown to accommodate the production of hydrogen gas by partially-deactivating O2 evolution activity, leading to anaerobiosis in a sealed culture. As these facets are coupled, and the system complex, mathematical approaches potentially are of significant value since they may reveal improved or even optimal schemes for maximizing hydrogen production. Here, a mechanistic model of the system is constructed from consideration of the essential pathways and processes. The role of sulfur in photosynthesis (via PSII) and the storage and catabolism of endogenous substrate, and thus growth and decay of culture density, are explicitly modeled in order to describe and explore the complex interactions that lead to H2 production during sulfur-deprivation. As far as possible, functional forms and parameter values are determined or estimated from experimental data. The model is compared with published experimental studies and, encouragingly, qualitative agreement for trends in hydrogen yield and initiation time are found. It is then employed to probe optimal external sulfur and illumination conditions for hydrogen production, which are found to differ depending on whether a maximum yield of gas or initial production rate is required. The model constitutes a powerful theoretical tool for investigating novel sulfur cycling regimes that may ultimately be used to improve the commercial viability of hydrogen gas production from microorganisms. Biotechnol. Bioeng. 2014;111: 320–335. © 2013 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc.

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      Most cited references 68

      • Record: found
      • Abstract: not found
      • Article: not found

      The Growth of Bacterial Cultures

       J MONOD (1949)
        • Record: found
        • Abstract: not found
        • Article: not found

        The solubility of nitrogen, oxygen and argon in water and seawater

         R.F. Weiss (1970)
          • Record: found
          • Abstract: not found
          • Article: not found

          Solar energy conversion efficiencies in photosynthesis: Minimizing the chlorophyll antennae to maximize efficiency


            Author and article information

            [1 ]British Antarctic Survey, Natural Environment Research Council High Cross, Madingley Road, Cambridge, CB3 0ET, UK
            [2 ]Department of Mathematics, University of York York, YO10 5DD, UK
            Author notes
            Correspondence to: C. R. Williams e-mail: chll1@

            Work conducted at School of Mathematics and Statistics, University of Glasgow, 15 University Gardens, Glasgow G12 8QW, UK.

            Contract grant sponsor: EPSRC

            Contract grant number: EP/D073398/1

            Biotechnol Bioeng
            Biotechnol. Bioeng
            Biotechnology and Bioengineering
            Wiley Periodicals, Inc.
            February 2014
            11 September 2013
            : 111
            : 2
            : 320-335
            © 2013 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc.

            This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.



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