Primary-amine oxidase

{{Short description|Class of enzymes}} {{Infobox enzyme | Name = Primary-amine oxidase | EC_number = 1.4.3.21 | CAS_number = | GO_code = | image = 2c10.jpg | width = 270 | caption = Amine oxidase (semicarbazide-sensitive) dimer, Human }} '''Primary-amine oxidase''', also known as '''semicarbazide-sensitive amine oxidase''' ('''SSAO'''),<ref name="Enzyme DB">{{cite web|author1=Andrew McDonald|title=Primary-amine oxidase|url=http://www.enzyme-database.org/query.php?ec=1.4.3.21|website=ExplorEnz – The Enzyme Database|publisher=International Union of Biochemistry and Molecular Biology|access-date=30 December 2015}}</ref><ref name="pmid21819380">{{cite journal | vauthors = Solé M, Unzeta M | title = Vascular cell lines expressing SSAO/VAP-1: a new experimental tool to study its involvement in vascular diseases | journal = Biology of the Cell | volume = 103 | issue = 11 | pages = 543–57 | date = Nov 2011 | pmid = 21819380 | doi = 10.1042/BC20110049 | s2cid = 4598444 }}</ref> is an enzyme ({{EC number|1.4.3.21}}) with the systematic name ''primary-amine:oxygen oxidoreductase (deaminating)''.<ref>{{cite journal | vauthors = Haywood GW, Large PJ | title = Microbial oxidation of amines. Distribution, purification and properties of two primary-amine oxidases from the yeast Candida boidinii grown on amines as sole nitrogen source | journal = The Biochemical Journal | volume = 199 | issue = 1 | pages = 187–201 | date = Oct 1981 | pmid = 7337701 | pmc = 1163349 | doi=10.1042/bj1990187}}</ref><ref>{{cite journal | vauthors = Tipping AJ, McPherson MJ | title = Cloning and molecular analysis of the pea seedling copper amine oxidase | journal = The Journal of Biological Chemistry | volume = 270 | issue = 28 | pages = 16939–46 | date = Jul 1995 | pmid = 7622512 | doi = 10.1074/jbc.270.28.16939 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Lyles GA | title = Mammalian plasma and tissue-bound semicarbazide-sensitive amine oxidases: biochemical, pharmacological and toxicological aspects | journal = The International Journal of Biochemistry & Cell Biology | volume = 28 | issue = 3 | pages = 259–74 | date = Mar 1996 | pmid = 8920635 | doi = 10.1016/1357-2725(95)00130-1 }}</ref><ref>{{cite journal | vauthors = Wilce MC, Dooley DM, Freeman HC, Guss JM, Matsunami H, McIntire WS, Ruggiero CE, Tanizawa K, Yamaguchi H | title = Crystal structures of the copper-containing amine oxidase from Arthrobacter globiformis in the holo and apo forms: implications for the biogenesis of topaquinone | journal = Biochemistry | volume = 36 | issue = 51 | pages = 16116–33 | date = Dec 1997 | pmid = 9405045 | doi = 10.1021/bi971797i }}</ref><ref>{{cite journal | vauthors = Lee Y, Sayre LM | title = Reaffirmation that metabolism of polyamines by bovine plasma amine oxidase occurs strictly at the primary amino termini | journal = The Journal of Biological Chemistry | volume = 273 | issue = 31 | pages = 19490–4 | date = Jul 1998 | pmid = 9677370 | doi = 10.1074/jbc.273.31.19490 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Houen G | title = Mammalian Cu-containing amine oxidases (CAOs): new methods of analysis, structural relationships, and possible functions | journal = APMIS | volume = 107 | issue = S96 | pages = 1–46 | year = 1999 | pmid = 10668504 | doi = 10.1111/apm.1999.107.s96.5 | s2cid = 34224347 }}</ref><ref>{{cite journal | vauthors = Andrés N, Lizcano JM, Rodríguez MJ, Romera M, Unzeta M, Mahy N | title = Tissue activity and cellular localization of human semicarbazide-sensitive amine oxidase | journal = The Journal of Histochemistry and Cytochemistry | volume = 49 | issue = 2 | pages = 209–17 | date = Feb 2001 | pmid = 11156689 | doi = 10.1177/002215540104900208 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Saysell CG, Tambyrajah WS, Murray JM, Wilmot CM, Phillips SE, McPherson MJ, Knowles PF | title = Probing the catalytic mechanism of Escherichia coli amine oxidase using mutational variants and a reversible inhibitor as a substrate analogue | journal = The Biochemical Journal | volume = 365 | issue = Pt 3 | pages = 809–16 | date = Aug 2002 | pmid = 11985492 | pmc = 1222726 | doi = 10.1042/BJ20011435 }}</ref><ref>{{cite journal | vauthors = O'Sullivan J, Unzeta M, Healy J, O'Sullivan MI, Davey G, Tipton KF | title = Semicarbazide-sensitive amine oxidases: enzymes with quite a lot to do | journal = Neurotoxicology | volume = 25 | issue = 1–2 | pages = 303–15 | date = Jan 2004 | pmid = 14697905 | doi = 10.1016/S0161-813X(03)00117-7 | bibcode = 2004NeuTx..25..303O }}</ref><ref>{{cite journal | vauthors = Airenne TT, Nymalm Y, Kidron H, Smith DJ, Pihlavisto M, Salmi M, Jalkanen S, Johnson MS, Salminen TA | title = Crystal structure of the human vascular adhesion protein-1: unique structural features with functional implications | journal = Protein Science | volume = 14 | issue = 8 | pages = 1964–74 | date = Aug 2005 | pmid = 16046623 | pmc = 2279308 | doi = 10.1110/ps.051438105 }}</ref> This enzyme catalyses the following chemical reaction

: RCH2NH2 + H2O + O2 <math>\rightleftharpoons</math> RCHO + NH3 + H2O2

These enzymes are copper quinoproteins (2,4,5-trihydroxyphenylalanine quinone).

Like monoamine oxidase (MAO), SSAO can deaminate short-chain primary amines, but is insensitive to MAO inhibitors. Semicarbazide inhibits the enzyme, in addition to other hydrazines, hydroxylamine and propargylamine. However, hydrazines are weak inhibitors and stronger inhibitors have been developed.

SSAO is found in the smooth muscle of blood vessels and various other tissues. The physiological function of SSAO is not well understood. Development of blood vessels, lipolysis regulation, and detoxication are suggested. It may function as a scavenger enzyme to assist MAO. However, the oxidation process generates harmful products that may be involved in causing atherosclerosis and vascular damage in diabetes. Elevation of SSAO activity is observed in atherosclerosis, diabetes mellitus, obesity, carotid plaque cases and varicosities.

There are SSAO inhibitors in development.<ref>{{cite journal |vauthors=O'Rourke AM, Wang EY, Miller A, etal|s2cid=5217225 |title=Anti-inflammatory effects of LJP 1586 [Z-3-fluoro-2-(4-methoxybenzyl)allylamine hydrochloride], an amine-based inhibitor of semicarbazide-sensitive amine oxidase activity |journal=The Journal of Pharmacology and Experimental Therapeutics |volume=324 |issue=2 |pages=867–75 |year=2008 |pmid=17993604 |doi=10.1124/jpet.107.131672 }}</ref><ref>{{cite journal |vauthors=Wang EY, Gao H, Salter-Cid L, etal|title=Design, synthesis, and biological evaluation of semicarbazide-sensitive amine oxidase (SSAO) inhibitors with anti-inflammatory activity |journal=Journal of Medicinal Chemistry |volume=49 |issue=7 |pages=2166–73 |year=2006 |pmid=16570912 |doi=10.1021/jm050538l }}</ref>

==Human proteins containing this domain== *AOC2 *AOC3 {{clear}}

==Bacterial proteins containing this domain== *Tyramine oxidase (tynA) in ''Escherichia coli''<ref name="BRENDA tynA">{{cite web|title=EC 1.4.3.21 – primary-amine oxidase and Organism(s) Escherichia coli, Escherichia coli K-12|url=https://www.brenda-enzymes.org/enzyme.php?ecno=1.4.3.21&Suchword=&reference=&UniProtAcc=&organism%5B%5D=Escherichia+coli&organism%5B%5D=Escherichia+coli+K-12|website=BRENDA|publisher=Technische Universität Braunschweig|access-date=8 August 2019}}</ref><ref name="pmid26556595">{{cite journal | vauthors = Elovaara H, Huusko T, Maksimow M, Elima K, Yegutkin GG, Skurnik M, Dobrindt U, Siitonen A, McPherson MJ, Salmi M, Jalkanen S | title = Primary Amine Oxidase of Escherichia coli Is a Metabolic Enzyme that Can Use a Human Leukocyte Molecule as a Substrate | journal = PLOS ONE | volume = 10 | issue = 11 | article-number = e0142367 | date = 2015 | pmid = 26556595 | pmc = 4640556 | doi = 10.1371/journal.pone.0142367 | bibcode = 2015PLoSO..1042367E | doi-access = free }}</ref>

== References == {{reflist|33em}}

== External links == * {{MeshName|Primary-amine+oxidase}}

Category:EC 1.4.3