Within this MSCA postdoctoral fellowship project, the gold-binding peptide enzymes mutants with gold-binding affinity that retain most of enzyme activity were identified, produced, and investigated. These findings lay the groundwork for further investigation into potential enzymes and materials relevant to desired biotechnological applications. Next, the researcher has successfully identified and recombinantly produced two redox metalloenzymes as model enzymes, a tungsten-selenocysteine formate dehydrogenase and a eukaryotic nitrate reductase, which are involved in two critical reactions, CO2 to formate and nitrate reduction, respectively. Specifically, a CO2 reductase is a highly valuable and important enzyme because of its ability to directly convert CO2 to formate. This result is of interest for potential scientific collaborations with the scientific community working on CO2 reduction applications, including biocatalysis, enzymatic cascades, enzymatic electrosynthesis, and light-driven CO2 reduction. In fact, as the production of tungsten-selenocysteine formate dehydrogenase in higher yield capable of CO2 reduction activity is being optimized at the time of writing, this will directly impact contemporary societal challenges (climate change and global warming) by facilitating an important step towards achieving the goal of upcycling CO2 into energy-rich long-chain compounds, representing a substantial opportunity to tackle environmental issues and achieve a circular economy. This aligns with the core ambition of the European Green Deal. In addition, the researcher has successfully established the production of yeast nitrate reductase in E. coli and subsequently worked on its engineering to have an enzyme with increased KM for use in nitrate quantification in plants, and therefore would be of scientific as well as economic impact for the agricultural sector.
