Rob Schmitz, Postdoctoral researcher at TU Delft

Rob Schmitz, postdoctoral researcher at Delft University of Technology, is fascinated by microorganisms and their enzymes and aims to apply them in #sustainable ways.

In November 2021, he obtained his PhD from Radboud University on the metabolism of extremely acidophilic methane-oxidizing bacteria. Hereafter, he worked for two years as a postdoc at ETH Zürich (Switzerland), where he investigated microbial turnover of carbon in peat soil.

Recently, he took up a postdoctoral project within the W-BioCat consortium. This project focuses on the cultivation of an amazing and extreme #microorganism that grows optimally at the temperature at which water boils. This microorganism harbours tungsten-containing enzymes that #catalyse all kinds of fascinating reactions that can be used to make the chemical industry more sustainable.

In the project, he will thoroughly study and characterize these enzymes to grasp their functioning, which will render valuable information needed to apply these enzymes on a large industrial scale.

Peter-Leon Hagedoorn’s group

Peter-Leon Hagedoorn’s group at Delft University of Technology, focuses on the elucidation of reaction mechanisms of (metallo-)enzymes containing heme, Fe-S clusters and/or W/Mo cofactors. We use microsecond timescale rapid mixing techniques, unique in the world, employed in a continuous flow UV-vis spectrophotometric device called Nanospec, and a rapid freeze hyperquench device called MHQ.

These techniques are circa 100 times faster than commercial instruments, and both techniques have been very powerful in the discovery of novel transient intermediates in the heme enzyme chlorite dismutase and Cu2+ binding to ATCUN/NTS motif peptides. In recent years Hagedoorn ventured together with prof. Hanefeld into enzyme immobilization and flow biocatalysis using Mn2+ dependent aldolases and hydroxynitrile lyases as well as thermophilic glycosyl transferases and hydratases (including FeS cluster containing enzymes).

Within the W-BioCat project, our focus is on the recombinant expression and characterization of W-containing aldehyde oxidoreductases (AORs). Heterologous expression of W-enzymes is challenging due to the requirement of an efficient W-cofactor biosynthesis pathway. The W-BioCat strains developed in this project will enable expression of new W-enzymes from genetic databases, and facilitate production of new engineered W-enzymes.

OxyCat group

The research of the OxyCat group, led by Frank Hollmann at Delft University of Technology, focuses on the establishment of new #redox chemistry using #biocatalysts.

One focus of the group lies on #oxyfunctionalisation reactions, i.e. oxidations where an oxygen atom is introduced into C-H-, C-C-, C=C-bonds. Performing these transformations selectively with traditional chemistry is notoriously difficult. A particular focus in the OxyCat group lies on Peroxygenases as #catalysts. These H2O2-dependent heme oxygenases excel by their robustness against hostile reaction conditions and their catalytic performance. Our objective is to develop reaction conditions allowing for their economical use. This entails, medium engineering to achieve product concentrations above 100 gL-1, reaction engineering to maximise the catalytic performance of the #biocatalyst and establish scalable 𝘪𝘯 𝘴𝘪𝘵𝘶 H2O2 generation systems.

Within the W-BioCat project, our focus will lie on the exploration of W-containing aldehyde oxidoreductases (AORs) for the #catalytic reduction of #carboxylic acids. In earlier studies, we have demonstrated the principal feasibility H2- or syngas-driven acid reductions using 𝑃𝑦𝑟𝑜𝑐𝑜𝑐𝑐𝑢𝑠 𝑓𝑢𝑟𝑖𝑜𝑠𝑢𝑠. The high selectivity of this reduction reaction and the controllable degree of reduction offers exciting possibilities for the valorisation of (waste) fatty acids as building blocks for chemical synthesis and as performance additives.