Light-driven hydrogen production by a hybrid complex of a [NiFe]-hydrogenase and the cyanobacterial photosystem I
Light-driven hydrogen production by a hybrid complex of a [NiFe]-hydrogenase and the cyanobacterial photosystem I
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DOI：
10.1562/2006-01-16-ra-778
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发表时间：
2006-05-01
影响因子：
3.3
通讯作者：
Okura, Ichiro
中科院分区：
文献类型：
--
作者：
Ihara, Masaki;Nishihara, Hirofumi;Okura, Ichiro
为了产生可再生和清洁的燃料，越来越多的努力集中在利用光合微生物从水和光生产分子氢上。在这项研究中，我们设计了一个“硬连线”的蛋白质复合物组成的9氢化酶和光系统I（氢化酶PSI复合物）作为一个直接的光到氢的转换系统。的关键组成部分是一个人工融合蛋白组成的膜结合[NiFe]氢化酶从β-变形杆菌Ralstonia eutropha H16和外周PSI亚基PsaE的蓝细菌Thermosy-nechococcus elongatus。所得的氢化酶-PsaE融合蛋白自发地与不含PsaE的PSI结合，从而形成氢化酶-PSI复合物，这一点通过蔗糖梯度超速离心和免疫印迹分析证实。氢化酶-PSI复合物以0.58 μ mol H-2中心点mg叶绿素（-1）中心点h（-1）的速率显示光驱动的氢产生。该复合物保持了其对天然电子受体铁氧还蛋白的可及性。这项研究提供了氧化还原酶和光系统I之间的人工复合物的光驱动酶促反应的第一个例子，代表了设计有效将太阳能和水转化为氢气的光合生物的重要一步。
In order to generate renewable and clean fuels, increasing efforts are focused on the exploitation of photosynthetic microorganisms for the production of molecular hydrogen from water and light. In this study we engineered a 'hard-wired' protein complex consisting of 9 hydrogenase and photosystem I (hydrogenase-PSI complex) as a direct light-to-hydrogen conversion system. The key component was an artificial fusion protein composed of the membrane-bound [NiFe] hydrogenase from the beta-proteobacterium Ralstonia eutropha H16 and the peripheral PSI subunit PsaE of the cyanobacterium Thermosy-nechococcus elongatus. The resulting hydrogenase-PsaE fusion protein associated with PsaE-free PSI spontaneously, thereby forming a hydrogenase-PSI complex as confirmed by sucrose-gradient ultracentrifuge and immunoblot analysis. The hydrogenase-PSI complex displayed light-driven hydrogen production at a rate of 0.58 mu mol H-2 center dot mg chlorophyll(-1)center dot h(-1). The complex maintained its accessibility to the native electron acceptor ferredoxin. This study provides the first example of a light-driven enzymatic reaction by an artificial complex between a redox enzyme and photosystem I and represents an important step on the way to design a photosynthetic organism that efficiently converts solar energy and water into hydrogen.