View source for Blasticidin-S deaminase

{{enzyme
| Name = creatinase
| EC_number = 3.5.3.3
| CAS_number = 37340-58-2
| IUBMB_EC_number = 3/5/3/3
| GO_code = 0016980
| image = 
| width = 
| caption = 
}}
{{Pfam_box 
| Symbol = Creatinase_N 
| Name = Creatinase/Prolidase N-terminal domain 
| image = 3O5V.pdb.jpg
| width = 
| caption = The Crystal Structure of the Creatinase/Prolidase N-terminal domain of an X-PRO dipeptidase from Streptococcus pyogenes to 1.85A <ref name="urlRCSB Protein Data Bank - Structure Summary for 3O5V - The Crystal Structure of the Creatinase/Prolidase N-terminal domain of an X-PRO dipeptidase from Streptococcus pyogenes to 1.85A">{{cite web |url=http://www.rcsb.org/pdb/explore/explore.do?structureId=3O5V |title=RCSB Protein Data Bank - Structure Summary for 3O5V - The Crystal Structure of the Creatinase/Prolidase N-terminal domain of an X-PRO dipeptidase from Streptococcus pyogenes to 1.85A |format= |work= |accessdate=}}</ref>
| Pfam= PF01321
| InterPro= IPR000587
| SMART= 
| Prosite =          
| SCOP = 1chm
| TCDB = 
| OPM family= 
| OPM protein= 
| PDB= 
{{PDB3|1wn1}}B:2-131     {{PDB3|1chm}}A:27-158    {{PDB3|1kp0}}B:27-157    
{{PDB3|1pv9}}B:4-124     {{PDB3|1wy2}}B:7-127     
}} 
In [[enzymology]], a '''creatinase''' ({{EC number|3.5.3.3}}) is an [[enzyme]] that [[catalysis|catalyzes]] the [[chemical reaction]]

:creatine + H<sub>2</sub>O <math>\rightleftharpoons</math> sarcosine + urea

Thus, the two [[substrate (biochemistry)|substrates]] of this enzyme are [[creatine]] and [[water|H<sub>2</sub>O]], whereas its two [[product (chemistry)|products]] are [[sarcosine]] and [[urea]].

The native enzyme was shown to be made up of two subunit monomers via SDS-polyacrylamide gel electrophoresis. The molecular weights of these subunits was estimated to be 47,000 g/mol.<ref name="pmid8443">{{cite journal |author=Yoshimoto T, Oka I, Tsuru D |title=Purification, crystallization, and some properties of creatine amidinohydrolase from Pseudomonas putida |journal=J. Biochem. |volume=79 |issue=6 |pages=1381–3 |year=1976 |month=June |pmid=8443 |doi= |url=}}</ref> The enzyme works as a homodimer, and is induced by choline chloride. Each monomer of creatinase has two clearly defined domains, a small N-terminal domain, and a large C-terminal domain. Each of the two active sites is made by residues of the large domain of one monomer and some residues of the small domain of the other monomer. It's been suggested that a sulfhydryl group is located on or near the active site of the enzyme following inhibition experiments.<ref name="pmid8443" /> Creatinase has been found to be most active at pH 8 and is most stable between ph 6-8 for 24 hrs. at 37 degrees.<ref name="pmid8443" />

This enzyme belongs to the family of [[hydrolase]]s, those acting on carbon-nitrogen bonds other than peptide bonds, specifically in linear amidines.  The systematic name of this enzyme class is '''creatine amidinohydrolase'''. This enzyme participates in [[arginine and proline metabolism]].

==Structural studies==

As of late 2007, two [[tertiary structure|structures]] have been solved for this class of enzymes, with [[Protein Data Bank|PDB]] accession codes {{PDB link|1CHM}} and {{PDB link|1KP0}}.

==References==
{{cite web |url=http://www.rcsb.org/pdb/explore/explore.do?structureId=3O5V |title=RCSB Protein Data Bank - Structure Summary for 3O5V - The Crystal Structure of the Creatinase/Prolidase N-terminal domain of an X-PRO dipeptidase from Streptococcus pyogenes to 1.85A |format= |work= |accessdate=}}
{{reflist|1}}
* {{cite journal | author = ROCHE J, LACOMBE G, GIRARD H | year = 1950 | title = [On the specificity of certain bacterial deguanidases generating urea and on arginindihydrolase.] | journal = Biochim. Biophys. Acta.  | volume = 6 | pages = 210&ndash;6  | pmid = 14791411 | issue = 1 }}
* {{cite journal | author = Yoshimoto T, Oka I, Tsuru D | date = Tokyo | title = Purification, crystallization, and some properties of creatine amidinohydrolase from Pseudomonas putida | journal = J.  | volume = Biochem. | pages = 1381&ndash;3  | pmid = 8443 | issue = 6 }}

[[Category:EC 3.5.3]]
[[Category:Enzymes of known structure]]


{{hydrolase-stub}}