Protein subunit

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As a protein subunit , or short subunit is referred to in the Structural Biology a single protein - the molecule , which aggregates with other protein molecules and with them a functional protein (specifically protein complex forms). If the subunits are identical, one speaks of a homomeric protein complex , and different subunits of a heteromeric protein complex.

Many enzymes , ion channels , receptors , structural proteins and others are oligomeric or multimeric proteins, i.e. they consist of several different subunits. Each such subunit consists of a polypeptide chain . Since different protein molecules are involved in multimeric proteins, and one gene codes for each individual protein molecule , several genes are involved in the coding of multimeric proteins.

example

  • Hemoglobin is a tetrameric protein made up of four subunits ; So hemoglobin is a tetramer. There are two α and two β subunits, so hemoglobin is heteromeric.

literature

  • Jeremy M. Berg, John L. Tymoczko, Lubert Stryer : Biochemistry. 6 edition, Spektrum Akademischer Verlag, Heidelberg 2007. ISBN 978-3-8274-1800-5 .
  • Donald Voet, Judith G. Voet: Biochemistry. 3rd edition, John Wiley & Sons, New York 2004. ISBN 0-471-19350-X .
  • Bruce Alberts , Alexander Johnson, Peter Walter, Julian Lewis, Martin Raff, Keith Roberts: Molecular Biology of the Cell , 5th Edition, Taylor & Francis 2007, ISBN 978-0815341062 .