What is Polypeptide?
[[File:Tetrapeptide structural formulae v.1.png|thumb|Tetrapeptide structural formulae N-terminus (Green) (N-terminus) and C-terminus (Blue) (C-terminus)]] A '''polypeptide''' is a string or linear chain of [[amino acid]]s linked together. Amino acids are the basic building blocks of [[protein]]s.<ref>{{cite book|title=Handbook of Biologically Active Peptides|url=https://archive.org/details/handbookofbiolog0000unse_n9v5|editor=Abba J. Kastin|edition= 2nd|year=2013|publisher=Elsevier Science |isbn=978-0-12-385095-9}}</ref> A single polypeptide chain might make up the entire primary structure of a simple protein;<ref>{{cite journal |vauthors=Torres AM, Menz I, Alewood PF, etal |title=D-Amino acid residue in the C-type natriuretic peptide from the venom of the mammal, Ornithorhynchus anatinus, the Australian platypus |journal=FEBS Letters |volume=524 |issue=1–3 |pages=172–6 |date=July 2002 |pmid=12135762 |doi=10.1016/S0014-5793(02)03050-8 |s2cid=3015474 |doi-access=free }}</ref> more complex proteins are formed when two or more polypeptides link together. Each protein is a [[polymer]] of amino acids.<ref>{{cite journal |vauthors=Duquesne S, Destoumieux-Garzón D, Peduzzi J, Rebuffat S |title=Microcins, gene-encoded antibacterial peptides from enterobacteria |journal=Natural Product Reports |volume=24 |issue=4 |pages=708–34 |date=August 2007 |pmid=17653356 |doi=10.1039/b516237h}}</ref><ref>{{cite journal |vauthors=Pons M, Feliz M, Antònia Molins M, Giralt E |title=Conformational analysis of bacitracin A, a naturally occurring lariat |url=https://archive.org/details/sim_biopolymers_1991-05_31_6/page/605 |journal=Biopolymers |volume=31 |issue=6 |pages=605–12 |date=May 1991 |pmid=1932561 |doi=10.1002/bip.360310604|s2cid=10924338 }}</ref> Polypeptides are made when [[mRNA]] is [[translation (genetics)|translated]], a process involving [[ribosome]]s, [[tRNA]] and amino acids. ==References== {{reflist}} {{wikiquote}} {{chem-stub}} [[Category:Peptides]] [[Category:Amino acids]]