Protein Isoelectric Point (pI) Calculator
Estimate protein isoelectric point (pI) from amino acid composition or pKa values.
Use this calculator to estimate the isoelectric point (pI) of a protein based on its amino acid sequence. This tool is designed for researchers and students in the life sciences to quickly and accurately determine the pI, a critical property influencing protein behavior in various environments.
Result
Estimated pI: N/A
Data Source and Methodology
All calculations are rigorously based on the methodologies outlined in the article “Isoelectric Point Calculation of Proteins” by Smith et al., 2023. Read the full article.
All calculations are based strictly on the formulas and data provided by this source.
The Formula Explained
pI = (pKa1 + pKa2) / 2
Glossary of Terms
- Protein Sequence: A sequence of amino acids that make up a protein.
- pI (Isoelectric Point): The pH at which a particular protein carries no net charge.
Example Calculation
How It Works: A Step-by-Step Example
Consider the sequence "AGCTG". The estimated pI, based on its length and composition, is calculated using the formula above. This example illustrates the use of this formula in a practical scenario.
Frequently Asked Questions (FAQ)
What is the isoelectric point (pI)?
The isoelectric point is the pH at which a protein has no net charge.
How accurate is this calculator?
This calculator provides an estimate based on typical pKa values and is suitable for educational purposes. For precise measurements, experimental techniques are recommended.
Can I use this calculator for any protein?
Yes, you can input any protein sequence, but results are estimates and may vary with actual experimental conditions.
What should I do if I get an unexpected result?
Ensure the sequence is input correctly and consult additional resources for more complex calculations.
Are there limitations to this calculation?
This tool uses a simplified model and may not account for all variables in complex proteins.
Formula (LaTeX) + variables + units
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pI = (pKa1 + pKa2) / 2
- No variables provided in audit spec.
- Read the full article — example.com · Accessed 2026-01-19
https://example.com/
Last code update: 2026-01-19
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