Related Experiment Video
Updated: Jul 5, 2026
04:01
Revealing the Ferroptotic Phenotype of Medulloblastoma
Published on: March 15, 2024
The ferrous-oxy complex of human aromatase
Yelena V Grinkova1, Ilia G Denisov, Michael R Waterman
1Department of Biochemistry, Center for Biophysics and Computational Biology, University of Illinois, Urbana, IL 61801, USA.
Biochemical and Biophysical Research Communications
|May 17, 2008
Summary
Researchers stabilized human aromatase (CYP19) in Nanodiscs, enabling detailed study of its reaction cycle. The ferrous-oxy complex of aromatase is surprisingly stable, offering new insights into this drug target.
Area of Science:
- Biochemistry
- Structural Biology
- Enzymology
Background:
- Human aromatase (CYP19) is crucial for estrogen biosynthesis and a significant drug target.
- Understanding CYP19's reaction mechanism is vital for drug development.
- Previous studies faced challenges in characterizing reaction intermediates.
Purpose of the Study:
- To develop a stable, functional preparation of truncated human aromatase (CYP19).
- To investigate the biochemical and biophysical properties of CYP19 reaction cycle intermediates.
- To compare the stability of CYP19 intermediates with other cytochrome P450 enzymes.
Main Methods:
- Heterologous expression and self-assembly of truncated human aromatase into Nanodiscs.
- Spectroscopic analysis of enzyme-substrate complex formation.
- Rapid-scan stopped-flow spectroscopy to monitor reaction kinetics.
- Anaerobic mixing with dioxygen to form and characterize the ferrous-oxy complex.
Main Results:
- Successfully assembled stable Nanodiscs containing functional truncated human aromatase (CYP19).
- Observed tight association of CYP19 with androstenedione, forming a high-spin ferric protein.
- Characterized the ferrous-oxy complex of CYP19 using stopped-flow kinetics.
- Demonstrated that the ferrous-oxy complex of aromatase is more stable than that of CYP3A4.
Conclusions:
- Nanodisc technology provides a robust system for studying human aromatase.
- The enhanced stability of the ferrous-oxy complex facilitates detailed mechanistic studies.
- This work paves the way for precise biochemical and biophysical characterization of CYP19 intermediates.
- Provides a foundation for understanding and targeting CYP19 in drug discovery.
Related Concept Videos
01:28The Early Endosome: Endocytosis of Transferrin
Essential proteins such as insulin or low-density lipoprotein (LDL) and micronutrients such as iron enter a eukaryotic cell through receptor-mediated endocytosis. Subsequently, the early endosomes fuse with the vesicles containing such receptor-ligand complexes and play a vital role in sorting the incoming ligands and receptors. While the ligands are either degraded inside the vesicle or released into the cytosol, their receptors are returned to the plasma membrane for further rounds of...
01:43Electron Transport Chain: Complex III and IV
During the electron transport chain, electrons from NADH and FADH2 are first transferred to complexes I and II, respectively. These two complexes then transfer the electrons to ubiquinol, which carries them further to complex III. Complex III passes the electrons across the intermembrane space to Cyt c, which carries them further to complex IV. Complex IV donates electrons to oxygen and reduces it to water. As electrons pass through complexes I, III, and IV, the energy released aids the pumping...
01:46Electron Transport Chain: Complex I and II
The mitochondrial electron transport chain (ETC) is the main energy generation system in the eukaryotic cells. However, mitochondria also produce cytotoxic reactive oxygen species (ROS) due to the large electron flow during oxidative phosphorylation. While Complex I is one of the primary sources of superoxide radicals, ROS production by Complex II is uncommon and may only be observed in cancer cells with mutated complexes.
ROS generation is regulated and maintained at moderate levels necessary...
ROS generation is regulated and maintained at moderate levels necessary...
01:41The Supercomplexes in the Crista Membrane
The mitochondrial cristae membrane is the primary site for the oxidative phosphorylation (OXPHOS) process of energy conversion mediated through respiratory complexes I to V. These complexes have been widely studied for decades, and it has been proven that they form supramolecular structures called respiratory supercomplexes (SC). These higher-order complexes may be crucial in maintaining the biochemical structure and improving the physiological activity of the individual complexes while...
01:30The Electron Transport Chain
The electron transport chain or oxidative phosphorylation is an exothermic process in which free energy released during electron transfer reactions is coupled to ATP synthesis. This process is a significant source of energy in aerobic cells, and therefore inhibitors of the electron transport chain can be detrimental to the cell's metabolic processes.
Inhibitors of the electron transport chain
Rotenone, a widely used pesticide, prevents electron transfer from Fe-S cluster to ubiquinone or Q in...
Inhibitors of the electron transport chain
Rotenone, a widely used pesticide, prevents electron transfer from Fe-S cluster to ubiquinone or Q in...
01:31Ferromagnetism
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...