4nix

Publication Abstract from PubMed

Although site-specific incorporation of artificial functionalities into proteins is an important tool in both basic and applied research, it can be a major challenge to protein chemists. Enzymatic protein modification is an attractive goal due to the inherent regio- and stereoselectivity of enzymes, yet their specificity remains a problem. As a result of the intrinsic reversibility of enzymatic reactions, proteinases can in principle catalyze ligation reactions. While this makes them attractive tools for site-specific protein bioconjugation, competing hydrolysis reactions limits their general use. Here we describe the design and application of a highly specific trypsin variant for the selective modification of N-terminal residues of diverse proteins with various reagents. The modification proceeds quantitatively under native (aqueous) conditions. We show that the variant has a disordered zymogen-like activation domain, effectively suppressing the hydrolysis reaction, which is converted to an active conformation in the presence of appropriate substrates.

N-Terminal Protein Modification by Substrate-Activated Reverse Proteolysis.,Liebscher S, Schopfel M, Aumuller T, Sharkhuukhen A, Pech A, Hoss E, Parthier C, Jahreis G, Stubbs MT, Bordusa F Angew Chem Int Ed Engl. 2014 Feb 12. doi: 10.1002/anie.201307736. PMID:24520050^[1]

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