Related Experiment Video
Updated: Aug 9, 2026

Real-time In Vitro Monitoring of Odorant Receptor Activation by an Odorant in the Vapor Phase
Published on: April 23, 2019
A single lysyl residue defines the binding specificity of a human odorant-binding protein for aldehydes
Lionel Tcatchoff1, Claude Nespoulous, Jean-Claude Pernollet
1Biochimie de l'olfaction et de la gustation, Neurobiologie de l'Olfaction et de la Prise Alimentaire, UMR 1197 - INRA-Université Paris XI, INRA, Domaine de vilvert, Bâtiment 526, F 78352 Jouy-en-Josas Cedex, France.
Abstract:
Odorant-binding proteins (OBPs) are small abundant soluble proteins belonging to the lipocalin superfamily, which are thought to carry hydrophobic odorants through aqueous mucus towards olfactory receptors. Human variant hOBP-2A has been demonstrated to bind numerous odorants of different chemical classes with a higher affinity for aldehydes and fatty acids. Three lysyl residues of the binding pocket (Lys62, Lys82 and Lys112) have been suggested as candidates for playing such a role. Here, using site-directed mutagenesis and fluorescent probe displacements, we show that Lys112 is the major determinant for governing hOBP-2A specificity towards aldehydes and small carboxylic acids.
Related Concept Videos
Structures of Aldehydes and Ketones
In aldehydes (Figures 1a and 1b), the carbonyl...
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...
Ligand Binding and Linkage
Allosteric Proteins-ATCase
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis pathway,...
NMR Spectroscopy and Mass Spectrometry of Aldehydes and Ketones
Cooperative Allosteric Transitions

