Engineering non-native metal active sites into proteins using canonical amino acids offers many advantages but is hampered by significant challenges. The TIM barrel protein, imidazole glycerol phosphate synthase from the hyperthermophilic organism Thermotoga maritima (tHisF), is well-suited for the construction of artificial metalloenzymes by this approach. To this end, we have generated a tHisF variant (tHisF) with a Glu/His/His motif for metal ion coordination.
View Article and Find Full Text PDFThe perfluoroheteroaromatic reagent pentafluoropyridine has proved to be a highly reactive electrophile, undergoing SAr arylation reactions in the presence of a range of nucleophilic peptide side chains (i.e. cysteine, tyrosine, serine and lysine) under mild conditions.
View Article and Find Full Text PDFThe SAr arylation of peptides with perfluoroaromatics provides a route by which to install a useful chemical handle that enables both F-NMR analysis and further chemical modification. However, chemo-selective arylation in peptides containing multiple nucleophilic side chains currently presents a challenge to the field. Herein, we demonstrate that employing 2,2,2-trifluoroethanol (TFE) as a solvent in peptide SAr reactions significantly improves nucleophile-selectivity when compared to N,N'-dimethylformamide (DMF).
View Article and Find Full Text PDFSelf-assembling block copolypeptides were prepared by sequential ring-opening polymerization of N-carboxyanhydride (NCA) derivatives of γ-benzyl-L-glutamic acid and ε-carbobenzyloxy-L-lysine, followed by selective deprotection of the benzyl glutamate block. The synthesized polymers had number average molecular weights close to theoretical values, and had low dispersities (ĐM = 1.15-1.
View Article and Find Full Text PDF6-Hydrazinonicotinic acid (HYNIC, 1) is a well-established bifunctional technetium-binding ligand often used to synthesise bioconjugates for radiolabelling with Tc-99m. It is capable of efficient capture of technetium at extremely low concentrations, but the structure of the labelled complexes is heterogeneous and incompletely understood. In particular, it is of interest to determine whether, at the no-carrier-added level, it acts in a chelating or non-chelating mode.
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