5w72

Publication Abstract from PubMed

The impact of the incorporation of a non-natural amino acid (NNAA) onto protein structure, dynamics, and ligand binding has not been studied rigorously so far. NNAAs are regularly used to modify proteins post-translationally in vivo and in vitro using click-chemistry. Here, we present a structural characterization of the impact of the incorporation of azidohomoalanine (AZH) into the model protein domain PDZ3 using NMR spectroscopy and X-ray crystallography. The structure and dynamics of the apo state of the AZH-modified PDZ3 remains mostly unperturbed. Furthermore, the binding of two PDZ3 binding peptides are found to be unchanged by incorporation of AZH. We mapped the interface of the AZH-modified PDZ3 and an azulene-linked peptide for vibrational energy transfer studies using chemical shift perturbations and NOEs between the unlabelled azulene-linked peptide and the isotopically labelled protein. Co-crystallization and soaking failed for the peptide-bound holo-complex. NMR spectroscopy, however, al-lowed determination of the protein-ligand interface. While the incorpo-ration of AZH was minimally invasive for PDZ3, structural analysis of NNAA-modified proteins by the methodology presented here should be carried out to ensure structural integrity of the studied target.

The Impact of Azidohomoalanine Incorporation on Protein Structure and Ligand Binding.,Lehner F, Kudlinzki D, Richter C, Muller-Werkmeister H, Eberl K, Bredenbeck J, Schwalbe H, Silvers R Chembiochem. 2017 Sep 26. doi: 10.1002/cbic.201700437. PMID:28950050^[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.