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A simplified electrophoretic system for determining molecular weights of proteins
The Biochemical Journal
|September 1, 1977
Summary
This study introduces a novel electrophoresis method using polyacrylamide gradient gels to accurately determine protein molecular weights. The technique offers a reliable and efficient way to measure molecular weight, simplifying protein analysis.
Area of Science:
- Biochemistry
- Molecular Biology
- Proteomics
Background:
- Accurate molecular weight determination is crucial for protein identification and characterization.
- Existing methods for molecular weight determination using polyacrylamide gel electrophoresis can be complex and time-consuming.
Purpose of the Study:
- To develop a novel, accurate, and efficient method for determining protein molecular weights using electrophoresis.
- To establish a linear relationship between gel pore size and molecular weight for a wide range of proteins.
Main Methods:
- Electrophoresis of 31 different proteins using commercially prepared polyacrylamide gradient gels (Gradipore).
- Analysis of the relationship between limiting gel concentration (GL) and the cube root of molecular weight (mol.wt.).
- Regression analysis to determine the accuracy of the method.
Main Results:
- A linear relationship was observed between the reciprocal of GL and the cube root of mol.wt. for proteins ranging from 13,500 to 9,000,000 Da.
- Regression analysis showed that molecular weight explained 98.6% of the variability in 1/GL, indicating high accuracy.
- The method allows for the use of readily available biological samples as molecular weight standards.
Conclusions:
- This electrophoresis technique provides a highly accurate and reliable method for determining protein molecular weights.
- The procedure is advantageous due to the accessibility of molecular weight standards and its compatibility with routine protein analysis.
- This method simplifies protein characterization and population studies of protein variation.
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