Enhancing plasma membrane NADPH oxidase activity increases current output by diatoms in biophotovoltaic devices
Enhancing plasma membrane NADPH oxidase activity increases current output by diatoms in biophotovoltaic devices
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DOI：
10.1016/j.algal.2015.08.009
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发表时间：
2015-11-01
影响因子：
5.1
通讯作者：
Smith, Alison G.
中科院分区：
文献类型：
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作者：
Laohavisit, Anuphon;Anderson, Alexander;Smith, Alison G.
生物光伏（BPV）装置利用微藻或蓝细菌的光合作用活性来收获光能，并且由于从藻类细胞释放电子而直接产生电流。NADPH氧化酶（NOX）是质膜酶，其从胞质溶胶运输电子以产生细胞外超氧阴离子，并且已经涉及BPV输出。在这项研究中，我们调查了氮氧化物的活性在硅藻三角褐指藻和海链藻，试图了解和增强氮氧化物和BPV的功能。我们发现，氮氧化物的活性与确定的生长制度和生长阶段，是光依赖性。重要的是，BPV装置中的电流输出与NOX活性相关，并且获得了每10（6）个电池高达14 μ A（约500 mA·m（-2））的水平。发现两个推定的三角褐指藻NOX基因（PtNOX 1和PtNOX 2）的表达与观察到的超氧阴离子产生和功率输出的生长模式相对应，表明这些是观察到的NOX活性模式的原因。至关重要的是，我们证明，NOX活性水平可以通过半连续培养提高，指出在BPV设备中保持长期功率输出的可能性。(C)2015年，作者。由Elsevier B出版。诉
Biophotovoltaic (BPV) devices employ the photosynthetic activity of microalgae or cyanobacteria to harvest light energy and generate electrical current directly as a result of the release of electrons from the algal cells. NADPH oxidases (NOX) are plasma-membrane enzymes that transport electrons from the cytosol to generate extracellular superoxide anions, and have been implicated in BPV output. In this study, we investigated NOX activity in the diatoms Phaeodactylum tricornutum and Thalassiosira pseudonana in an attempt to understand and enhance NOX and BPV function. We found that NOX activity was linked to defined growth regimes and growth phases, and was light dependent. Crucially, current output in a BPV device correlated with NOX activity, and levels of up to 14 mu A per 10(6) cells (approximately 500 mA.m(-2)) were obtained. Expression of two putative P. tricornutum NOX genes (PtNOX1 and PtNOX2) was found to correspond with the observed growth patterns of superoxide anion production and power output, suggesting that these are responsible for the observed patterns of NOX activity. Crucially, we demonstrate that NOX activity levels could be enhanced via semi-continuous culturing, pointing to the possibility of maintaining long-term power output in BPV devices. (C) 2015 The Authors. Published by Elsevier B. V.