Bioconjugations of proteins with 19F and nitroxide tags for in vitro and in cell characterization

This thesis involves the application of various tag topologies, from 19F moieties to nitroxide spin labels. The former were investigated to explore novel alternatives for post-expression covalent modification of tyrosine residues, providing valuable approaches for preparing 19F NMR samples. On the other hand, four different nitroxide spin probes bound to cysteine residues were compared to assess their different behaviour while attached on two different secondary structural elements (α-helix and the β-sheet). Lastly, one nitroxide spin label was also utilized for in-cell studies on both Escherichia coli and Pichia pastoris through EPR spectroscopy.