Hydrogen production through oxygenic photosynthesis using the cyanobacterium Synechocystis sp. PCC 6803 in a bio-photoelectrolysis cell (BPE) system

• DOI: 10.1039/c3ee40491a
• Publication Date: 2013-07-12T10:00:38Z
• Authors: Alistair J. McCor...; Paolo Bombelli; David J. Lea-Smith; Robert W. Bradley; Amanda M. Scott; Adrian C. Fisher; Alison G. Smith; Christopher J. Howe
• Keywords: Wild type; Synechocystis; Photoelectrolysis; Photobioreactor

Microbial electrolysis cells (MECs) represent an emerging technology that uses heterotrophic microbes to convert organic substrates into fuel products, such as hydrogen gas (H2). The recent development of biophotovoltaic (BPVs), which use autotrophic produce electricity with only light a substrate, raises the possibility exploiting similar systems harness photosynthesis drive production H2. In current study we explore capacity cyanobacterium Synechocystis sp. PCC 6803 generate electrons by oxygenic and facilitate H2 in two-chamber bio-photoelectrolysis cell (BPE) system using electron mediator potassium ferricyanide ([Fe(CN)6]3−). performance wild-type mutant strain lacking all three respiratory terminal oxidase activities (rto) was compared under low or high salt conditions. rto showed decrease maximum photosynthetic rates (60% lower Pmax than wild-type) but significantly increased salt, comparable levels. Remarkably, demonstrated 3-fold increase (Fe[CN]6)3− reduction both wild-type. Yields efficiency parameters were between rto, highest conditions, resulting rate 2.23 ± 0.22 ml l−1 h−1 (0.68 0.11 mmol [mol Chl]−1 s−1). dependent on application bias-potential, voltages used less required for water electrolysis. These results clearly show cyanobacteria is feasible without need inhibit O2 evolution. Optimising balance microbial-facilitated may lead long-term sustainable yields.