Protein trimer

In biochemistry, a protein trimer is a macromolecular complex formed by three, usually non-covalently bound, macromolecules like proteins or nucleic acids. A protein trimer often occurs from the assembly of a protein's quaternary structure.^[1] The non-covalent interactions between the hydrophobic and hydrophilic regions on the polypeptides units help to stabilize the quaternary structure. Since a protein trimer is composed of multiple polypeptide subunits, it is considered an oligomer.^[2]

A homotrimer would be formed by three identical molecules.^[3] A heterotrimer would be formed by three different macromolecules. Type II Collagen is an example of homotrimeric protein, while Type I collagen is an AAB-type heterotrimeric protein.

Porins usually arrange themselves in membranes as trimers.

^ Godbey, W.T. (2014), "Proteins", An Introduction to Biotechnology, Elsevier, pp. 9–33, doi:10.1016/b978-1-907568-28-2.00002-2, ISBN 978-1-907568-28-2, retrieved 2024-05-03
^ Pelley, John W. (2012-01-01), Pelley, John W. (ed.), "3 - Protein Structure and Function", Elsevier's Integrated Review Biochemistry (Second Edition), Philadelphia: W.B. Saunders, pp. 19–28, doi:10.1016/b978-0-323-07446-9.00003-9, ISBN 978-0-323-07446-9, retrieved 2024-05-03
^ Cha, S.S.; et al. (1998). "High resolution crystal structure of a human tumor necrosis factor-alpha mutant with low systemic toxicity". J. Biol. Chem. 273 (4): 2153–60. doi:10.1074/jbc.273.4.2153. PMID 9442056.

[1] Godbey, W.T. (2014), "Proteins", An Introduction to Biotechnology, Elsevier, pp. 9–33, doi:10.1016/b978-1-907568-28-2.00002-2, ISBN 978-1-907568-28-2, retrieved 2024-05-03

[2] Pelley, John W. (2012-01-01), Pelley, John W. (ed.), "3 - Protein Structure and Function", Elsevier's Integrated Review Biochemistry (Second Edition), Philadelphia: W.B. Saunders, pp. 19–28, doi:10.1016/b978-0-323-07446-9.00003-9, ISBN 978-0-323-07446-9, retrieved 2024-05-03

[3] Cha, S.S.; et al. (1998). "High resolution crystal structure of a human tumor necrosis factor-alpha mutant with low systemic toxicity". J. Biol. Chem. 273 (4): 2153–60. doi:10.1074/jbc.273.4.2153. PMID 9442056.

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