Editing Amino acid (section)

==History==

The first few amino acids were discovered in the early 1800s.<ref>{{cite journal | vauthors = Vickery HB, Schmidt CL | year = 1931 | title = The history of the discovery of the amino acids | journal = Chem. Rev. | volume = 9 | issue = 2| pages = 169–318 | doi=10.1021/cr60033a001}}</ref><ref>{{cite web | vauthors = Hansen S |title=Die Entdeckung der proteinogenen Aminosäuren von 1805 in Paris bis 1935 in Illinois |location=Berlin |date=May 2015 |url=https://www.arginium.de/wp-content/uploads/2015/12/Entdeckung-der-Aminos%C3%A4uren.pdf |archive-url=https://web.archive.org/web/20171201232937/https://www.arginium.de/wp-content/uploads/2015/12/Entdeckung-der-Aminos%C3%A4uren.pdf |archive-date=1 December 2017 |language=de}}</ref> In 1806, French chemists [[Louis-Nicolas Vauquelin]] and [[Pierre Jean Robiquet]] isolated a compound from [[asparagus]] that was subsequently named [[asparagine]], the first amino acid to be discovered.<ref>{{Cite journal|title=The discovery of a new plant principle in Asparagus sativus |vauthors=Vauquelin LN, Robiquet PJ |journal=Annales de Chimie |year=1806 |volume=57 |pages=88–93}}</ref><ref name=Anfinsen>{{Cite book |title=Advances in Protein Chemistry |vauthors=Anfinsen CB, Edsall JT, Richards FM |year=1972 |pages=[https://archive.org/details/advancesinprotei26anfi/page/99 99, 103] |publisher=Academic Press |location=New York |isbn=978-0-12-034226-6 |url=https://archive.org/details/advancesinprotei26anfi/page/99 }}</ref> [[Cystine]] was discovered in 1810,<ref>{{Cite journal|title=On cystic oxide, a new species of urinary calculus | vauthors = Wollaston WH |s2cid=110151163 |journal=Philosophical Transactions of the Royal Society |year=1810 |volume=100|pages=223–230 |doi=10.1098/rstl.1810.0015}}</ref> although its monomer, [[cysteine]], remained undiscovered until 1884.<ref>{{Cite journal |title=Über cystin und cystein | vauthors = Baumann E |journal=Z Physiol Chem |year=1884 |volume=8 |issue=4 |pages=299–305 |url=http://vlp.mpiwg-berlin.mpg.de/library/data/lit16533 |access-date=28 March 2011 |archive-url=https://web.archive.org/web/20110314075450/http://vlp.mpiwg-berlin.mpg.de/library/data/lit16533 |archive-date=14 March 2011 |url-status=dead }}</ref><ref name=Anfinsen/>{{efn|The late discovery is explained by the fact that cysteine becomes oxidized to cystine in air.}} [[Glycine]] and [[leucine]] were discovered in 1820.<ref>{{Cite journal|title=Sur la conversion des matières animales en nouvelles substances par le moyen de l'acide sulfurique | vauthors = Braconnot HM |journal=Annales de Chimie et de Physique |series=2nd Series |year=1820 |volume=13 |pages=113–125}}</ref> The last of the 20 common amino acids to be discovered was [[threonine]] in 1935 by [[William Cumming Rose]], who also determined the [[essential amino acid]]s and established the minimum daily requirements of all amino acids for optimal growth.<ref>{{cite journal | vauthors = Simoni RD, Hill RL, Vaughan M | title = The discovery of the amino acid threonine: the work of William C. Rose [classical article] | journal = The Journal of Biological Chemistry | volume = 277 | issue = 37 | pages = E25 | date = September 2002 | pmid = 12218068 | doi = 10.1016/S0021-9258(20)74369-3 | doi-access = free }}</ref><ref>{{cite journal|title=Feeding Experiments with Mixtures of Highly Purified Amino Acids. VIII. Isolation and Identification of a New Essential Amino Acid|vauthors = McCoy RH, Meyer CE, Rose WC|year = 1935|journal = Journal of Biological Chemistry|volume = 112|pages = 283–302|doi = 10.1016/S0021-9258(18)74986-7|doi-access = free}}</ref>

The unity of the chemical category was recognized by [[Charles Adolphe Wurtz|Wurtz]] in 1865, but he gave no particular name to it.<ref>Menten, P. ''Dictionnaire de chimie: Une approche étymologique et historique''. De Boeck, Bruxelles. [https://books.google.com/books?id=NKTKDgAAQBAJ link] {{Webarchive|url=https://web.archive.org/web/20191228193229/https://books.google.com/books?id=NKTKDgAAQBAJ |date=28 December 2019 }}.</ref> The first use of the term "amino acid" in the English language dates from 1898,<ref>{{cite web |url=https://www.etymonline.com/word/amino- | vauthors = Harper D |work=Online Etymology Dictionary |title=amino- |access-date=19 July 2010 |archive-date=2 December 2017 |archive-url=https://web.archive.org/web/20171202102757/https://www.etymonline.com/word/amino- |url-status=live }}</ref> while the German term, {{lang|de|Aminosäure}}, was used earlier.<ref>{{cite journal | vauthors = Paal C | year = 1894 | title = Ueber die Einwirkung von Phenyl-i-cyanat auf organische Aminosäuren | journal = Berichte der Deutschen Chemischen Gesellschaft | volume = 27 | pages = 974–979 | doi = 10.1002/cber.189402701205 | url = https://zenodo.org/record/1425732 | archive-url = https://web.archive.org/web/20200725075835/https://zenodo.org/record/1425732 | url-status = dead | archive-date = 2020-07-25 }}</ref> [[Protein]]s were found to yield amino acids after enzymatic digestion or acid [[hydrolysis]]. In 1902, [[Hermann Emil Fischer|Emil Fischer]] and [[Franz Hofmeister]] independently proposed that proteins are formed from many amino acids, whereby bonds are formed between the amino group of one amino acid with the carboxyl group of another, resulting in a linear structure that Fischer termed "[[peptide]]".<ref>{{cite book | vauthors = Fruton JS | title = Contrasts in Scientific Style: Research Groups in the Chemical and Biochemical Sciences |volume=191 |year=1990 |chapter=Chapter 5- Emil Fischer and Franz Hofmeister |chapter-url=https://books.google.com/books?id=tRlC9NyNNN8C&pg=PA163 |pages=163–165 |publisher=American Philosophical Society |isbn=978-0-87169-191-0 }}</ref>