Related Experiment Video
Updated: Jun 14, 2026
10:39
Visualization of ATP Synthase Dimers in Mitochondria by Electron Cryo-tomography
Published on: September 14, 2014
A functionally active dimer of mycobacterium tuberculosis malate synthase G.
1Division of Molecular and Structural Biology, Central Drug Research Institute, Lucknow 226 001, India. drkumar.ranjeet@gmail.com
European Biophysics Journal : EBJ
|March 23, 2010
Summary
Malate synthase G in mycobacterium exists as both monomer and dimer. The dimeric form is more stable and resistant to proteolysis, suggesting dimerization regulates enzyme stability and function.
Area of Science:
- Biochemistry
- Molecular Biology
- Microbiology
Background:
- Malate synthase G is a key housekeeping enzyme in the mycobacterial glyoxylate shunt.
- Its intracellular/extracellular localization, adhesin, and virulence factor roles are not fully understood.
- Limited knowledge exists regarding its biophysical and biochemical properties, crucial for mycobacterial persistence.
Purpose of the Study:
- To investigate the quaternary structure and stability of malate synthase G.
- To explore the role of enzyme dimerization in its stability and function.
- To elucidate the relationship between malate synthase G's structure, stability, and diverse biological roles.
Main Methods:
- Biophysical characterization techniques (e.g., spectroscopy, sedimentation analysis) were used.
- Biochemical assays were employed to assess enzyme activity and stability.
- Proteolysis studies were conducted to compare monomeric and dimeric forms.
Main Results:
- Malate synthase G exists in both active monomer and dimer forms under physiological conditions.
- The dimeric form exhibits significantly higher stability compared to the monomeric form.
- The dimeric enzyme demonstrates enhanced resistance to proteolysis.
Conclusions:
- Dimerization appears to be a critical regulatory mechanism for malate synthase G stability.
- Differential localization and non-enzymatic functions may influence dimer stabilization and activity modulation in vivo.
- Understanding these properties is vital for targeting mycobacterial persistence mechanisms.
More Related Videos
11:27X-Ray Crystallography to Study the Oligomeric State Transition of the Thermotoga maritima M42 Aminopeptidase TmPep1050
Published on: May 13, 2020
09:27Functional Complementation Analysis (FCA): A Laboratory Exercise Designed and Implemented to Supplement the Teaching of Biochemical Pathways
Published on: June 24, 2016
Related Concept Videos
01:48ATP Synthase: Mechanism
In animals, the mitochondrial F1F0 ATP synthase is the key protein that synthesizes ATP molecules through a complex catalytic mechanism. While the nuclear genome encodes the majority of ATP synthase subunits, the mitochondrial genome encodes some of the enzyme's most critical components. The formation of this multi-subunit enzyme is a complex multi-step process regulated at the level of transcription, translation, and assembly. Defects in one or more of these steps can result in decreased ATP...
01:18ATP Synthase: Structure
ATP synthase or ATPase is among the most conserved proteins found in bacteria, mammals, and plants. This enzyme can catalyze a forward reaction in response to the electrochemical gradient, producing ATP from ADP and inorganic phosphate. ATP synthase can also work in a reverse direction by hydrolyzing ATP and generating an electrochemical gradient. Different forms of ATP synthases have evolved special features to meet the specific demands of the cell. Based on their specific feature, ATP...
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...
01:15Overview of Myosin Structure and Function
Myosins are a family of molecular motor proteins, first identified in the skeletal muscles, where they are responsible for muscle contraction. Along with their role in muscle contraction, these proteins also play a role in the intracellular transport of molecules and vesicles. There are twenty-four classes of myosins based on their domain sequence and organization. Of the twenty-four, six classes (Myosin I, Myosin II, Myosin V, Myosin VI, Myosin VII, and Myosin X) have been well characterized.
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...
01:43Electron 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...