View source for Cysteine dioxygenase

{{Infobox enzyme
| Name = Cysteine dioxygenase
| EC_number = 1.13.11.20
| CAS_number = 37256-59-0
| IUBMB_EC_number = 1/13/11/20
| GO_code = 
| image = 
| width = 
| caption =
}}
{{infobox protein
|Name=cysteine dioxygenase, type I
|caption=
|image=
|width=
|HGNCid=1795
|Symbol=CDO1
|AltSymbols=
|EntrezGene=1036
|OMIM=603943
|RefSeq=NM_001801
|UniProt=Q16878
|PDB=
|ECnumber=1.13.11.20
|Chromosome=5
|Arm=q
|Band=23.2
|LocusSupplementaryData=
}}
'''Cysteine dioxygenase''' ('''CDO''', [[CAS number]]: 37256-59-0) is a [[mammalian]] non-[[heme]] iron [[enzyme]] that [[catalyze]]s the conversion of L-[[cysteine]] to [[cysteine sulfinic acid]] (cysteine sulfinate) via the incorporation of two [[dioxygen]]-derived oxygens. Large concentrations of cysteine are toxic, and have been implicated in Parkinson's and Alzheimer's. CDO is also a tumor suppressor enzyme, that helps to prevent metastases by oxidizing the protective layer of cysteine that tumors surround themselves with in order to evade chemo- and radiation-generated hydroxyl radicals. 


[[Image:Cysteine-dioxygenase-reaction.png|frame|none|''CDO reaction scheme showing cysteine sulfinic acid formation from cysteine by dioxygen incorporation'']]



'''Mechanism''' The CDO mechanism is not well understood, but has been proposed to involve [[dioxygen]](O2) binding cis to a thiolate to form reactive RS-Fe-[[superoxide]] (RS-Fe-O2•–), Fe-sulfenate (RS-O; a deprotonated [[sulfenic acid]],<ref name="pmid28033001">{{cite journal | vauthors = Villar-Acevedo G, Lugo-Mas P, Blakely MN, Rees JA, Ganas AS, Hanada EM, Kaminsky W, Kovacs JA, Brines, LM | title = Metal-Assisted Oxo Atom Addition to an Fe(III) Thiolate | journal = J. Am. Chem. Soc. | volume = 139 | issue = 1 | pages = 119-129 |date=January 2017 | pmid = 28033001 | doi = 10.1021/jacs.6b03512| pmc = 5262503 }}</ref> and [[high-valent iron]]-oxo intermediates. A reactive RS-Fe-[[superoxide]] (RS-Fe-O2•–) intermediate is also involved in the mechanism of [[Isopenicillin N synthase]] (IPNS), however, rather than form an S-O bond, IPNS catalyzes C-S bond formation via [[hydrogen atom abstraction]].

Cysteine sulfinic acid lies at a branch-point in [[cysteine catabolism]], where it can follow two pathways resulting in the formation of [[taurine]] or [[sulfate]]. The cysteine sulfinic acid-dependent pathway of taurine metabolism follows the synthesis of [[hypotaurine]] (2-aminoethane sulfinate) which is subsequently oxidized to taurine. Also, cysteine sulfinate can undergo transamination to form [[β-sulfinylpyruvate]], decomposing to form [[pyruvate]] and [[sulfite]].

== References ==
* {{cite journal | vauthors = Sakakibara S, Yamaguchi K, Hosokawa Y, Kohashi N, Ueda I | title = Purification and some properties of rat liver cysteine oxidase (cysteine dioxygenase) | journal = Biochimica et Biophysica Acta | volume = 422 | issue = 2 | pages = 273–9 | date = Feb 1976 | pmid = 2307 | doi = 10.1016/0005-2744(76)90138-8 }}
* {{cite journal | vauthors = Chai SC, Jerkins AA, Banik JJ, Shalev I, Pinkham JL, Uden PC, Maroney MJ | title = Heterologous expression, purification, and characterization of recombinant rat cysteine dioxygenase | journal = The Journal of Biological Chemistry | volume = 280 | issue = 11 | pages = 9865–9 | date = Mar 2005 | pmid = 15623508 | doi = 10.1074/jbc.M413733200 | url = http://www.jbc.org/cgi/pmidlookup?view=long&pmid=15623508 }}
* {{cite journal | vauthors = McCoy JG, Bailey LJ, Bitto E, Bingman CA, Aceti DJ, Fox BG, Phillips GN | title = Structure and mechanism of mouse cysteine dioxygenase | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 103 | issue = 9 | pages = 3084–9 | date = Feb 2006 | pmid = 16492780 | pmc = 1413891 | doi = 10.1073/pnas.0509262103 | url = http://www.pnas.org/cgi/pmidlookup?view=long&pmid=16492780 }}

{{refend}}

== External links ==
* {{UCSC genome browser|CDO1}}
* {{UCSC gene details|CDO1}}

{{Amino acid metabolism enzymes}}
{{Monooxygenases}}
{{Enzymes}}
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[[Category:EC 1.13.11]]


{{1.13-enzyme-stub}}