Related Experiment Video
Updated: Aug 15, 2025

Structural Biology and Analytical Chemistry Approaches for Characterizing C-Glycoside Metabolic Enzymes in Human Gut Microbiota
Published on: May 23, 2025
Structural insights into the effects of glycerol on ligand binding to cytochrome P450
Sergey Bukhdruker1, Tatsiana Varaksa2, Philipp Orekhov1
1Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudnyy 141701, Russian Federation.
Abstract:
New antitubercular drugs are vital due to the spread of resistant strains. Carbethoxyhexyl imidazole (CHImi) inhibits cytochrome P450 CYP124, which is a steroid-metabolizing enzyme that is important for the survival of Mycobacterium tuberculosis in macrophages. The available crystal structure of the CYP124-CHImi complex reveals two glycerol molecules in the active site. A 1.15 Å resolution crystal structure of the glycerol-free CYP124-CHimi complex reported here shows multiple conformations of CHImi and the CYP124 active site which were previously restricted by glycerol. Complementary molecular dynamics simulations show coherence of the ligand and enzyme conformations. Spectrophotometric titration confirmed the influence of glycerol on CHImi binding: the affinity decreases more than tenfold in glycerol-containing buffer. In addition, it also showed that glycerol has a similar effect on other azole and triazole CYP124 ligands. Together, these data show that glycerol may compromise structural-functional studies and impede rational drug-design campaigns.
Related Concept Videos
GPCRs Regulate Adenylyl Cylase Activity
Noncovalent Attractions in Biomolecules
Four types of noncovalent interactions are hydrogen bonds, van der Waals forces, ionic bonds, and hydrophobic interactions.
Hydrogen bonding results from the electrostatic attraction of a hydrogen atom covalently bonded to a strong-electronegative atom like oxygen,...
GPCR Desensitization
Ligand Binding and Linkage
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...
The Equilibrium Binding Constant and Binding Strength

