Protein Charge Determination

Donald J. Winzor1

1 University of Queensland, Brisbane, Queensland
Publication Name:  Current Protocols in Protein Science
Unit Number:  Unit 2.10
DOI:  10.1002/0471140864.ps0210s41
Online Posting Date:  September, 2005
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The most popular current method of determining protein valence entails the calculation of net charge from amino acid sequence/composition. However, the inaccuracy of that approach was recognized long before the advent of the protein data banks and computer programs to facilitate its adoption. Capillary zone electrophoresis affords the simplest and most economical procedure for obtaining a reliable estimate of the net charge of a protein in the buffer system of interest. This unit explains the major pitfalls in the calculation of net charge from protein sequence data.

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Table of Contents

  • Calculation of Protein Charge from Sequence Data
  • Electrophoretic Determination of Net Protein Charge
  • Relationship Between Mobility and Protein Charge
  • Valence Measurement by the “Charge Ladder” Approach
  • Concluding Remarks
  • Literature Cited
  • Figures
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Literature Cited

Literature Cited
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