Encyclopedia of Astrobiology

Living Edition
| Editors: Muriel Gargaud, William M. Irvine, Ricardo Amils, Henderson James Cleaves, Daniele Pinti, José Cernicharo Quintanilla, Michel Viso

Proteins, Quaternary Structure

  • Henderson James (Jim) CleavesII
Living reference work entry
DOI: https://doi.org/10.1007/978-3-642-27833-4_1325-4

Definition

Many proteins are composed of more than one folded polypeptide chain, which are known as protein subunits. Quaternary structure describes the organization of multiple subunits into a complex. Some examples of proteins with quaternary structure include hemoglobin and many ion channel proteins. Changes in quaternary structure can occur through conformational changes within individual subunits or through reorientation of the subunits relative to each other. These conformational changes, which may be cooperative or allosterically (induced by binding of other molecule) effected, often govern the mechanism by which proteins are regulated or perform their catalytic functions.

See Also

Keywords

Secondary Structure Conformational Change Bioorganic Chemistry Primary Structure Tertiary Structure 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Earth-Life Science Institute (ELSI), Tokyo Institute of TechnologyMeguro-kuJapan
  2. 2.Institute for Advanced StudyPrincetonUSA
  3. 3.Blue Marble Space Institute of ScienceWashingtonUSA
  4. 4.Center for Chemical Evolution, Georgia Institute of TechnologyAtlantaUSA