Oxidoreductase fusions: engineering enzymes for coupled reactions and stability

Research output: ThesisThesis fully internal (DIV)

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Abstract

Enzymes are the core of biological life. These tiny molecular machines can transform molecules, which enables organisms to grow. Aside from their biological role, enzymes are also used for various applications, such as: brewing of beer, making cheese, and removing dirt from clothes.
There is great interest in the application of enzymes for the production of useful compounds, such as: (bio)materials, (bio)fuels, medicine, and food additives. Compared to chemical processes, a process with enzymes is greener and more sustainable. However, enzymes from nature are often not stable enough for large-scale industrial application; they rapidly fall apart. Aside from this lack of stability, it is also difficult and costly to produce enzymes.

In this thesis, we studied the approach of producing two enzymes together, as one: enzyme fusion. Not only does this make the production of enzymes more favorable, in some cases the enzymes can directly work together in a 2-step process.

In the final research chapter, we used another approach to improve enzyme application: mutagenesis through computational predictions. Enzymes are composed of hundreds of amino acids, and single amino acids can be exchanged by mutagenesis. Each amino acid interacts with all neighbouring amino acids. By swapping an amino acid with another one of different shape and property, such that it can make more and better interactions with the neighbouring amino acids, we can fortify the enzyme’s structure. The mutated enzyme could nearly resist boiling water, while the original enzyme fell apart around 40 °C.
Original languageEnglish
QualificationDoctor of Philosophy
Awarding Institution
  • University of Groningen
Supervisors/Advisors
  • Fraaije, Marco, Supervisor
  • Janssen, Dick, Supervisor
  • Slotboom, Dirk, Assessment committee
  • Poelarends, Gerrit, Assessment committee
  • Kara, Selin, Assessment committee, External person
Award date19-Jun-2020
Place of Publication[Groningen]
Publisher
Print ISBNs978-94-034-2602-0
Electronic ISBNs978-94-034-2603-7
DOIs
Publication statusPublished - 2020

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