Lamont Ciaran M, Kelly Ciarán L, Pinske Constanze, Buchanan Grant, Palmer Tracy, Sargent Frank
School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK.
Present address: Oxford BioMedica, Windrush Court, Transport Way, Oxford OX4 6LT, UK.
Microbiology (Reading). 2017 May;163(5):649-653. doi: 10.1099/mic.0.000471.
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 ) 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 ferredoxin (Fd) and Hyd-3. The Fd-Hyd-3 fusion was found to evolve hydrogen when co-produced with 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.
在厌氧条件下产生专门用于氢代谢的酶。特别是，甲酸氢化酶（FHL）负责在发酵条件下产生的大部分氢气。FHL由直接与[NiFe]-氢化酶-3（Hyd-3）相连的甲酸脱氢酶（由……编码）组成，并且甲酸是已知的该氢化酶用于质子还原的唯一天然底物。在这项工作中，探索了设计用于产氢的替代电子供体的可能性。合理设计和基因工程导致构建了铁氧化还原蛋白（Fd）与Hyd-3之间的融合体。发现Fd-Hyd-3融合体在与丙酮酸::铁氧化还原蛋白氧化还原酶（PFOR）共同产生时会产生氢气，PFOR将丙酮酸氧化与铁氧化还原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了一条新的产氢途径上。
