Related Experiment Video
Updated: Aug 4, 2026
09:11
Screening for Thermotoga maritima Membrane-Bound Pyrophosphatase Inhibitors
Published on: November 23, 2019
Appendix II. The catalytic and stability properties of phosphorylated mammalian phosphoglycerate mutase
The Journal of Biological Chemistry
|September 25, 1986
Abstract:
Because of the critical nature of the experiments described, Sigma phosphoglycerate mutase was carefully examined for the possible occurrence of phosphorylated enzyme, using isotope-labeling techniques. Also, the influence of purposely formed phosphoryl enzyme on mutase catalysis in the absence of added 2,3-DPG was determined.
Insights
Researchers investigated Sigma phosphoglycerate mutase for phosphorylated enzyme forms using isotope labeling. They determined the impact of phosphoryl enzyme on mutase catalysis without 2,3-diphosphoglycerate (2,3-DPG).
Area of Science:
- Biochemistry
- Enzymology
Background:
- Phosphoglycerate mutase (PGM) is a key enzyme in glycolysis.
- The enzyme's catalytic mechanism and potential for endogenous phosphorylation are critical for understanding its function.
Purpose of the Study:
- To investigate the presence of phosphorylated Sigma phosphoglycerate mutase.
- To determine the effect of phosphoryl enzyme on mutase activity in the absence of 2,3-diphosphoglycerate (2,3-DPG).
Main Methods:
- Isotope-labeling techniques were employed to detect phosphorylated enzyme.
- Enzyme kinetics were studied to assess catalysis with purposely formed phosphoryl enzyme.
Main Results:
- The study carefully examined Sigma phosphoglycerate mutase for phosphorylated forms.
- The influence of phosphoryl enzyme on mutase catalysis without 2,3-DPG was determined.
Conclusions:
- The research provides insights into the catalytic properties of phosphoglycerate mutase.
- Understanding enzyme phosphorylation is crucial for elucidating metabolic pathways.
Related Concept Videos
01:02Phosphorylation
The addition or removal of phosphate groups from proteins is the most common chemical modification that regulates cellular processes. These modifications can affect the structure, activity, stability, and localization of proteins within cells as well as their interactions with other proteins.
During phosphorylation, protein kinases transfer the terminal phosphate group of ATP to specific amino acid side chains of substrate proteins. Serine, threonine, and tyrosine are the most commonly...
During phosphorylation, protein kinases transfer the terminal phosphate group of ATP to specific amino acid side chains of substrate proteins. Serine, threonine, and tyrosine are the most commonly...
02:54Protein Kinases and Phosphatases
Proteins undergo chemical modifications that trigger changes in the charge, structure, and conformation of the proteins. Phosphorylation, acetylation, glycosylation, nitrosylation, ubiquitination, lipidation, methylation, and proteolysis are various protein modifications that regulate protein activity. Such modifications are usually enzyme-driven.
Protein kinases
Many proteins in the cell are regulated by phosphorylation, the addition of a phosphate group. A family of enzymes called kinases...
Protein kinases
Many proteins in the cell are regulated by phosphorylation, the addition of a phosphate group. A family of enzymes called kinases...
02:04Covalently Linked Protein Regulators
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein.
These groups modify specific amino acids in a protein.
01:58Cell Specific Gene Expression
Multicellular organisms contain a variety of structurally and functionally distinct cell types, but the DNA in all the cells originated from the same parent cells. The differences in the cells can be attributed to the differential gene expression. Liver cells, whose functions include detoxification of blood, production of bile to metabolize fats, and synthesis of proteins essential for metabolism, must express a specific set of genes to perform their functions. Gene expression also varies with...
01:07Catalytically Perfect Enzymes
The theory of catalytically perfect enzymes was first proposed by W.J. Albery and J. R. Knowles in 1976. These enzymes catalyze biochemical reactions at high-speed. Their catalytic efficiency values range from 108-109 M-1s-1. These enzymes are also called 'diffusion-controlled' as the only rate-limiting step in the catalysis is that of the substrate diffusion into the active site. Examples include triose phosphate isomerase, fumarase, and superoxide dismutase.
01:13Introduction to Mechanisms of Enzyme Catalysis
For many years, scientists thought that enzyme-substrate binding took place in a simple "lock-and-key" fashion. This model stated that the enzyme and substrate fit together perfectly in one instantaneous step. However, current research supports a more refined view scientists call induced fit. The induced-fit model expands upon the lock-and-key model by describing a more dynamic interaction between enzyme and substrate. As the enzyme and substrate come together, their interaction causes a mild...