Halogen bonds involved in binding of halogenated ligands by protein kinases
Jarosław Poznański, Maria Winiewska, Honorata Czapinska, Anna Poznańska and David Shugar
Analysis of 664 known structures of protein kinase complexes with halogenated ligands revealed 424 short contacts between a halogen atom and a potential protein X-bond acceptor, the topology and geometry of which were analyzed according to the type of a halogen atom (X = Cl, Br, I) and a putative protein X-bond acceptor. Among 236 identified halogen bonds, the most represented ones are directed to backbone carbonyls of the hinge region and may replace the pattern of ATP-like hydrogen bonds. Some halogen-π interactions with either aromatic residues or peptide bonds, that accompany the interaction with the hinge region, may possibly enhance ligand selectivity. Interestingly, many of these halogen-π interactions are bifurcated. Geometrical preferences identify iodine as the strongest X-bond donor, less so bromine, while virtually no such preferences were observed for chlorine; and a backbone carbonyl as the strongest X-bond acceptor. The presence of a halogen atom in a ligand additionally affects the properties of proximal hydrogen bonds, which according to geometrical parameters get strengthened, when a nitrogen of a halogenated ligand acts as the hydrogen bond donor.
Acta Biochimica Polonica, 63(2), 203-214, Review, DOI: 10.18388/abp.2015_1106
Acta Biochimica Polonica is indexed in: Current Contents, Biochem. and Biophys. Citation Index, BIOSIS, Chemical Abstracts, Excerpta Medica, Medline, Index Copernicus, CBR
Acta Biochimica Polonica is a member of the Committee on Publication Ethics (COPE)
Copyright © by Pawel Pomorski and Polish Biochemical Society 2015