5KI3

PSEUDO T4 LYSOZYME MUTANT - Y18PHE-BR

Summary for 5KI3

• Entry DOI: 10.2210/pdb5ki3/pdb
• Related: 5KHZ 5KI1 5KI2 5KI8 5KIG 5KII 5KIM 5KIO
• Descriptor: Endolysin, 2-HYDROXYETHYL DISULFIDE (3 entities in total)
• Functional Keywords: halogen bonds, t4 lysozyme, hydrolase
• Biological source: Enterobacteria phage T4
• Total number of polymer chains: 1
• Total formula weight: 19674.39

Authors

Butta, H.W.,Scholfield, M.R. (deposition date: 2016-06-16, release date: 2017-04-12, Last modification date: 2023-11-15)

Primary citation

Scholfield, M.R.,Ford, M.C.,Carlsson, A.C.,Butta, H.,Mehl, R.A.,Ho, P.S.
Structure-Energy Relationships of Halogen Bonds in Proteins.
Biochemistry, 56:2794-2802, 2017

PubMed Abstract: The structures and stabilities of proteins are defined by a series of weak noncovalent electrostatic, van der Waals, and hydrogen bond (HB) interactions. In this study, we have designed and engineered halogen bonds (XBs) site-specifically to study their structure-energy relationship in a model protein, T4 lysozyme. The evidence for XBs is the displacement of the aromatic side chain toward an oxygen acceptor, at distances that are equal to or less than the sums of their respective van der Waals radii, when the hydroxyl substituent of the wild-type tyrosine is replaced by a halogen. In addition, thermal melting studies show that the iodine XB rescues the stabilization energy from an otherwise destabilizing substitution (at an equivalent noninteracting site), indicating that the interaction is also present in solution. Quantum chemical calculations show that the XB complements an HB at this site and that solvent structure must also be considered in trying to design molecular interactions such as XBs into biological systems. A bromine substitution also shows displacement of the side chain, but the distances and geometries do not indicate formation of an XB. Thus, we have dissected the contributions from various noncovalent interactions of halogens introduced into proteins, to drive the application of XBs, particularly in biomolecular design.

PubMed: 28345933
DOI: 10.1021/acs.biochem.7b00022

Experimental method

X-RAY DIFFRACTION (1.65 Å)