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Aspartic acid
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<h2 id="discovery">Discovery</h2> <p>Aspartic acid was first discovered in 1827 by <a href="/facts/Auguste-Arthur_Plisson/9BGF5e4Q">Auguste-Arthur Plisson</a> and <a href="/facts/%25C3%2589tienne-Ossian_Henry/xpcU3rol">Étienne-Ossian Henry</a><a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a><a class="footnote-ref" id="fnref:11" href="#fn:11"><sup>11</sup></a> by <a href="/facts/Hydrolysis/JTvwIHPs">hydrolysis</a> of <a href="/facts/Asparagine/KYIft5Jd">asparagine</a>, which had been isolated from <a href="/facts/Asparagus/MoI6GaCN">asparagus</a> juice in 1806.<a class="footnote-ref" id="fnref:12" href="#fn:12"><sup>12</sup></a> Their original method used <a href="/facts/Lead_hydroxide/sMxg7pee">lead hydroxide</a>, but various other acids or bases are now more commonly used instead. </p> <h2 id="forms-and-nomenclature">Forms and nomenclature</h2> <p>There are two forms or <a href="/facts/Enantiomer/wjPv5J3y">enantiomers</a> of aspartic acid. The name "aspartic acid" can refer to either enantiomer or a mixture of two.<a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a> Of these two forms, only one, "L-aspartic acid", is directly incorporated into proteins. The biological roles of its counterpart, "D-aspartic acid" are more limited. Where enzymatic synthesis will produce one or the other, most chemical syntheses will produce both forms, "DL-aspartic acid", known as a <a href="/facts/Racemic_mixture/STEagtrD">racemic mixture</a>. </p> <h2 id="synthesis">Synthesis</h2> <h3>Biosynthesis</h3> <p>In the human body, aspartate is most frequently synthesized through the <a href="/facts/Transamination/Ntj23r8y">transamination</a> of <a href="/facts/Oxaloacetate/ojLoQw81">oxaloacetate</a>. The biosynthesis of aspartate is facilitated by an <a href="/facts/Aminotransferase/5xt6gNd3">aminotransferase</a> enzyme: the transfer of an <a href="/facts/Amine/JvfYJfP6">amine</a> group from another molecule such as alanine or glutamine yields aspartate and an alpha-keto acid.<a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a> </p> <h3>Chemical synthesis</h3> <p>Industrially, aspartate is produced by amination of <a href="/facts/Fumarate/VDecBfLQ">fumarate</a> catalyzed by L-<a href="/facts/Aspartate_ammonia-lyase/bG77hxxq">aspartate ammonia-lyase</a>.<a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a> </p><p><a href="/facts/Racemic/STEagtrD">Racemic</a> aspartic acid can be synthesized from diethyl sodium phthalimidomalonate, (C6H4(CO)2NC(CO2Et)2).<a class="footnote-ref" id="fnref:16" href="#fn:16"><sup>16</sup></a> </p> <h2 id="metabolism">Metabolism</h2> <p>In plants and <a href="/facts/Microorganism/pysJYcE2">microorganisms</a>, aspartate is the precursor to several amino acids, including four that are essential for humans: <a href="/facts/Methionine/7neydPKo">methionine</a>, <a href="/facts/Threonine/7zffFQ6W">threonine</a>, <a href="/facts/Isoleucine/sJW4dxnh">isoleucine</a>, and <a href="/facts/Lysine/CEetgA9L">lysine</a>. The conversion of aspartate to these other amino acids begins with reduction of aspartate to its "semialdehyde", O2CCH(NH2)CH2CHO.<a class="footnote-ref" id="fnref:17" href="#fn:17"><sup>17</sup></a> <a href="/facts/Asparagine/KYIft5Jd">Asparagine</a> is derived from aspartate via transamidation: </p> −O2CCH(NH2)CH2CO2− + <i>G</i>C(O)NH3+ → O2CCH(NH2)CH2CONH3+ + <i>G</i>C(O)O <p>(where <i>G</i>C(O)NH2 and <i>G</i>C(O)OH are <a href="/facts/Glutamine/t94zX4SK">glutamine</a> and <a href="/facts/Glutamic_acid/7oXbNcvu">glutamic acid</a>, respectively) </p> <h2 id="other-biochemical-roles">Other biochemical roles</h2> <p>Aspartate has many other biochemical roles. It is a <a href="/facts/Metabolite/nAyywVtA">metabolite</a> in the <a href="/facts/Urea_cycle/rWjAo7DY">urea cycle</a><a class="footnote-ref" id="fnref:18" href="#fn:18"><sup>18</sup></a> and participates in <a href="/facts/Gluconeogenesis/Jj5THIHh">gluconeogenesis</a>. It carries reducing equivalents in the <a href="/facts/Malate-aspartate_shuttle/SyPXrDMF">malate-aspartate shuttle</a>, which utilizes the ready interconversion of aspartate and <a href="/facts/Oxaloacetate/ojLoQw81">oxaloacetate</a>, which is the oxidized (dehydrogenated) derivative of <a href="/facts/Malic_acid/mSbExe77">malic acid</a>. Aspartate donates one nitrogen atom in the biosynthesis of <a href="/facts/Inosine/TSjq4XxS">inosine</a>, the precursor to the <a href="/facts/Purine/9ogLp0Wc">purine</a> bases. In addition, aspartic acid acts as a hydrogen acceptor in a chain of ATP synthase. Dietary L-aspartic acid has been shown to act as an inhibitor of <a href="/facts/Beta-glucuronidase/ctR23pbs">Beta-glucuronidase</a>, which serves to regulate <a href="/facts/Enterohepatic_circulation/LV3typr9">enterohepatic circulation</a> of <a href="/facts/Bilirubin/HCHyCjkt">bilirubin</a> and bile acids.<a class="footnote-ref" id="fnref:19" href="#fn:19"><sup>19</sup></a> </p> <h3>Interactive pathway map</h3> <p><i>Click on genes, proteins and metabolites below to link to respective articles.</i><a class="footnote-ref" id="fnref:20" href="#fn:20"><sup>20</sup></a> </p> <h3>Neurotransmitter</h3> <p>Aspartate (the <a href="/facts/Conjugate_base/hohgQ07M">conjugate base</a> of aspartic acid) stimulates <a href="/facts/NMDA_receptor/BqMhXEbU">NMDA receptors</a>, though not as strongly as the amino acid neurotransmitter <a href="/facts/Glutamic_acid/7oXbNcvu">L-glutamate</a> does.<a class="footnote-ref" id="fnref:21" href="#fn:21"><sup>21</sup></a> Aspartate is the "A" in NMDA (N-methyl-D-aspartate receptor). </p> <h2 id="applications--market">Applications & market</h2> <p>In 2014, the global market for aspartic acid was 39.3 thousand <a href="/facts/Short_ton/b2fcrxHq">short tons</a> (35.7 thousand <a href="/facts/Tonne/gMymLmWv">tonnes</a>)<a class="footnote-ref" id="fnref:22" href="#fn:22"><sup>22</sup></a> or about $117 million annually.<a class="footnote-ref" id="fnref:23" href="#fn:23"><sup>23</sup></a> The three largest market segments include the U.S., Western Europe, and China. Current applications include biodegradable polymers (<a href="/facts/Polyaspartic_acid/mIymUHDd">polyaspartic acid</a>), low calorie sweeteners (<a href="/facts/Aspartame/KQL62MUN">aspartame</a>), scale and corrosion inhibitors, and resins. </p> <h3>Superabsorbent polymers</h3> <p>One area of aspartic acid market growth is <a href="/facts/Biodegradable/d1UW4dfR">biodegradable</a> <a href="/facts/Superabsorbent_polymer/5z2XSL3k">superabsorbent polymers</a> (SAP), and hydrogels.<a class="footnote-ref" id="fnref:24" href="#fn:24"><sup>24</sup></a> Around 75% of superabsorbent polymers are used in disposable <a href="/facts/Diaper/62wCE4YW">diapers</a> and an additional 20% is used for adult <a href="/facts/Urinary_incontinence/1hNsKRn9">incontinence</a> and <a href="/facts/Feminine_hygiene/HPeRg5yX">feminine hygiene</a> products. <a href="/facts/Polyaspartic_acid/mIymUHDd">Polyaspartic acid</a>, the polymerization product of aspartic acid, is a biodegradable substitute to <a href="/facts/Polyacrylate/3z6dXElL">polyacrylate</a>.<a class="footnote-ref" id="fnref:25" href="#fn:25"><sup>25</sup></a><a class="footnote-ref" id="fnref:26" href="#fn:26"><sup>26</sup></a><a class="footnote-ref" id="fnref:27" href="#fn:27"><sup>27</sup></a> </p> <h3>Additional uses</h3> <p>In addition to SAP, aspartic acid has applications in the <a href="/facts/Fertilizer/ysh3r6NJ">fertilizer industry</a>, where polyaspartate improves water retention and nitrogen uptake.<a class="footnote-ref" id="fnref:28" href="#fn:28"><sup>28</sup></a> </p> <h2 id="sources">Sources</h2> <h3>Dietary sources</h3> <p>Aspartic acid is not an <a href="/facts/Essential_amino_acid/Re9Rxb9I">essential amino acid</a>, which means that it can be synthesized from central metabolic pathway intermediates in humans, and does not need to be present in the diet. In <a href="/facts/Eukaryote/SkwyPLMA">eukaryotic</a> cells, roughly 1 in 20 amino acids incorporated into a protein is an aspartic acid,<a class="footnote-ref" id="fnref:29" href="#fn:29"><sup>29</sup></a> and accordingly almost any source of dietary protein will include aspartic acid. Additionally, aspartic acid is found in: </p> <ul><li><a href="/facts/Dietary_supplements/SHXNNxaS">Dietary supplements</a>, either as aspartic acid itself or <a href="/facts/Salt_(chemistry)/lsSKwGpn">salts</a> (such as <a href="/facts/Magnesium_aspartate/ITdEGKjl">magnesium aspartate</a>)</li> <li>The sweetener <a href="/facts/Aspartame/KQL62MUN">aspartame</a>, which is made from an aspartic acid and <a href="/facts/Phenylalanine/eyojfW7t">phenylalanine</a></li></ul> <h2 id="see-also">See also</h2> <ul><li><a href="/facts/Aspartate_transaminase/ksTwpdqx">Aspartate transaminase</a></li> <li><a href="/facts/Polyaspartic_acid/mIymUHDd">Polyaspartic acid</a></li> <li><a href="/facts/Sodium_polyaspartate/WEcuof8f">Sodium polyaspartate</a>, a synthetic <a href="/facts/Polyamide/8AmQgTFa">polyamide</a></li></ul> <h2 id="external-links">External links</h2> <ul><li><a href="http://gmd.mpimp-golm.mpg.de/Spectrums/E4577DF4-03FE-4AF1-ADBF-FFE6D1D3A468.aspx">GMD MS Spectrum</a></li> <li>American Chemical Society (21 April 2010). <a href="https://www.sciencedaily.com/releases/2010/04/100421121501.htm">"Ancestral Eve' Crystal May Explain Origin of Life's Left-Handedness"</a>. <i>ScienceDaily</i>. <a href="https://web.archive.org/web/20100423002752/https://www.sciencedaily.com/releases/2010/04/100421121501.htm">Archived</a> from the original on 23 April 2010. Retrieved 2010-04-21.</li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>"Nomenclature and Symbolism for Amino Acids and Peptides". IUPAC-IUB Joint Commission on Biochemical Nomenclature. 1983. Archived from the original on 9 October 2008. Retrieved 5 March 2018. <a href="https://web.archive.org/web/20081009023202/http://www.chem.qmul.ac.uk/iupac/AminoAcid/AA1n2.html" target="_blank">https://web.archive.org/web/20081009023202/http://www.chem.qmul.ac.uk/iupac/AminoAcid/AA1n2.html</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Voet, Donald; Voet, Judith G.; Pratt, Charlotte W. (2016-02-29). Fundamentals of Biochemistry: Life at the Molecular Level. John Wiley & Sons. ISBN 9781118918401. OCLC 910538334. <a href="9781118918401" target="_blank">9781118918401</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>D'Aniello, Antimo (1 February 2007). "d-Aspartic acid: An endogenous amino acid with an important neuroendocrine role". Brain Research Reviews. 53 (2): 215–234. doi:10.1016/j.brainresrev.2006.08.005. PMID 17118457. S2CID 12709991. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Huang AS, Beigneux A, Weil ZM, Kim PM, Molliver ME, Blackshaw S, Nelson RJ, Young SG, Snyder SH (March 2006). "D-aspartate regulates melanocortin formation and function: behavioral alterations in D-aspartate oxidase-deficient mice". The Journal of Neuroscience. 26 (10): 2814–9. doi:10.1523/JNEUROSCI.5060-05.2006. PMC 6675153. PMID 16525061. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6675153" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6675153</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>D'Aniello, Antimo (1 February 2007). "d-Aspartic acid: An endogenous amino acid with an important neuroendocrine role". Brain Research Reviews. 53 (2): 215–234. doi:10.1016/j.brainresrev.2006.08.005. PMID 17118457. S2CID 12709991. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>Voet, Donald; Voet, Judith G.; Pratt, Charlotte W. (2016-02-29). Fundamentals of Biochemistry: Life at the Molecular Level. John Wiley & Sons. ISBN 9781118918401. OCLC 910538334. <a href="9781118918401" target="_blank">9781118918401</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>Voet, Donald; Voet, Judith G.; Pratt, Charlotte W. (2016-02-29). Fundamentals of Biochemistry: Life at the Molecular Level. John Wiley & Sons. ISBN 9781118918401. 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ISBN 1-57259-153-6. <a href="1-57259-153-6" target="_blank">1-57259-153-6</a> <a href="#fnref:17" class="footnote-back-ref">↩</a></p></li> <li id="fn:18"><p>"Biochemistry - Biochemistry". www.varsitytutors.com. Retrieved 2022-02-18. <a href="https://www.varsitytutors.com/biochemistry-help/biochemistry?page=75" target="_blank">https://www.varsitytutors.com/biochemistry-help/biochemistry?page=75</a> <a href="#fnref:18" class="footnote-back-ref">↩</a></p></li> <li id="fn:19"><p>Kreamer, Bill L.; Siegel, Frank L.; Gourley, Glenn R. (Oct 2001). "A novel inhibitor of beta-glucuronidase: L-aspartic acid". Pediatric Research. 50 (4): 460–466. doi:10.1203/00006450-200110000-00007. 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