11. How Proteins Work

  1. Stephen R. Bolsover1,
  2. Jeremy S. Hyams2,
  3. Elizabeth A. Shephard3,
  4. Hugh A. White3 and
  5. Claudia G. Wiedemann1

Published Online: 27 JAN 2004

DOI: 10.1002/047146158X.ch11

Cell Biology: A Short Course, Second Edition

Cell Biology: A Short Course, Second Edition

How to Cite

Bolsover, S. R., Hyams, J. S., Shephard, E. A., White, H. A. and Wiedemann, C. G. (2003) How Proteins Work, in Cell Biology: A Short Course, Second Edition, John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/047146158X.ch11

Author Information

  1. 1

    Department of Physiology, University College, London, UK

  2. 2

    Department of Biology, University College, London, UK

  3. 3

    Department of Biochemistry and Molecular Biology, University College, London, UK

Publication History

  1. Published Online: 27 JAN 2004
  2. Published Print: 14 NOV 2003

ISBN Information

Print ISBN: 9780471263937

Online ISBN: 9780471461586

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Keywords:

  • ligand;
  • allostery;
  • phosphorylation;
  • enzyme;
  • catalytic rate constant;
  • Michaelis constant;
  • specificity constant;
  • activation energy;
  • cofactor;
  • prosthetic group

Summary

In this chapter we describe how proteins carry out their various tasks. Most bind other molecules - ligands - more or less specifically. Many change shape, and the preferred shape may be affected by pH or phosphorylation. Allostery occurs when ligand binding affects which shape is preferred. Enzymes are protein catalysts and can be analyzed in terms of their catalytic rate constant and their affinity for the substrate. The specificity constant allows comparison of different enzymes and substrates. Some enzymes use cofactors or prosthetic groups. Some can be allosterically regulated.