Expanding the substrates for a bacterial hydrogenlyase reaction.-猫眼课题宝

DOI：

10.1099/mic.0.000471

发表时间：

2017-05

期刊：

Microbiology (Reading, England)

影响因子：

通讯作者：

中科院分区：

其他

文献类型：

作者：

Lamont CM;Kelly CL;Pinske C;Buchanan G;Palmer T;Sargent F

来源链接：

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5817251/

大肠杆菌在厌氧条件下产生专门用于氢代谢的酶。特别地，甲酸氢解酶（FHL）负责在发酵条件下产生的大部分氢气。FHL包含与[NiFe]-氢化酶-3（Hyd-3）直接连接的甲酸脱氢酶（由fdhF编码），并且甲酸是已知用于通过该氢化酶进行质子还原的唯一天然底物。在这项工作中，工程的可能性替代电子供体制氢进行了探索。合理设计和基因工程导致海栖热袍菌铁氧还蛋白（Fd）和Hyd-3之间的融合构建。发现Fd-Hyd-3融合在与T. maritima pyruvate：：铁氧还蛋白氧化还原酶（PFOR），其将丙酮酸氧化与铁氧还蛋白的还原联系起来。对发酵过程中产生的关键有机酸的分析表明，PFOR/Fd-Hyd-3融合系统成功地将丙酮酸转移到一条新的制氢途径上。

Escherichia coli produces enzymes dedicated to hydrogen metabolism under anaerobic conditions. In particular, a formate hydrogenlyase (FHL) enzyme is responsible for the majority of hydrogen gas produced under fermentative conditions. FHL comprises a formate dehydrogenase (encoded by fdhF) linked directly to [NiFe]-hydrogenase-3 (Hyd-3), and formate is the only natural substrate known for proton reduction by this hydrogenase. In this work, the possibility of engineering an alternative electron donor for hydrogen production has been explored. Rational design and genetic engineering led to the construction of a fusion between Thermotoga maritima ferredoxin (Fd) and Hyd-3. The Fd-Hyd-3 fusion was found to evolve hydrogen when co-produced with T. maritima pyruvate :: ferredoxin oxidoreductase (PFOR), which links pyruvate oxidation to the reduction of ferredoxin. Analysis of the key organic acids produced during fermentation suggested that the PFOR/Fd-Hyd-3 fusion system successfully diverted pyruvate onto a new pathway towards hydrogen production.