Related Experiment Video
Updated: Jul 11, 2026

Fluorescence Anisotropy as a Tool to Study Protein-protein Interactions
Published on: October 21, 2016
Selectivity and affinity determinants for ligand binding to the aromatic amino acid hydroxylases
Knut Teigen1, Jeffrey Alan McKinney, Jan Haavik
1Department of Biomedicine, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway.
Abstract:
Hydroxylation of the aromatic amino acids phenylalanine, tyrosine and tryptophan is carried out by a family of non-heme iron and tetrahydrobiopterin (BH4) dependent enzymes, i.e. the aromatic amino acid hydroxylases (AAHs). The reactions catalyzed by these enzymes are important for biomedicine and their mutant forms in humans are associated with phenylketonuria (phenylalanine hydroxylase), Parkinson's disease and DOPA-responsive dystonia (tyrosine hydroxylase), and possibly neuropsychiatric and gastrointestinal disorders (tryptophan hydroxylase 1 and 2). We attempt to rationalize current knowledge about substrate and inhibitor specificity based on the three-dimensional structures of the enzymes and their complexes with substrates, cofactors and inhibitors. In addition, further insights on the selectivity and affinity determinants for ligand binding in the AAHs were obtained from molecular interaction field (MIF) analysis. We applied this computational structural approach to a rational analysis of structural differences at the active sites of the enzymes, a strategy that can help in the design of novel selective ligands for each AAH.
More Related Videos
06:50Computational Prediction of Amino Acid Preferences of Potentially Multispecific Peptide-Binding Domains Involved in Protein-Protein Interactions
Published on: January 26, 2024
10:01Structure-Guided Design and Development of Novel Cyclophilin A Inhibitors and Ganoderiol-F Derivatives: An In-Silico Approach
Published on: June 23, 2026
Related Concept Videos
Ligand Binding Sites
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
Conserved Binding Sites
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally analyses the...
Ligand Binding and Linkage
Ligand Binding and Linkage
Adrenergic Agonists: Chemistry and Structure-Activity Relationship
Aromatic ring substitutions: Substituting the aromatic ring with –OH groups at positions 3 and 4 yields catecholamines (e.g., epinephrine), which have a high affinity for adrenoceptors. Hydrogen bonding between –OH groups and receptors enhances adrenergic activity.
Separation of the aromatic...
Factors Affecting Protein-Drug Binding: Drug-Related Factors
One crucial factor in drug-protein binding is the drug's lipophilicity or its affinity for fat. More lipophilic drugs tend to have higher binding extents. For example, highly lipophilic drugs like cloxacillin exhibit substantial protein binding, with as much as 95% of the drug binding to proteins. In contrast,...