DB code: S00810

RLCP classification 4.12.642300.465 : Addition
5.201.1660000.464 : Elimination
CATH domain 3.40.140.10 : Cytidine Deaminase; domain 2 Catalytic domain
E.C. 3.5.4.3
CSA
M-CSA
MACiE

CATH domain Related DB codes (homologues)
3.40.140.10 : Cytidine Deaminase; domain 2 S00808 D00406

Uniprot Enzyme Name
UniprotKB Protein name Synonyms RefSeq Pfam
O34598 Guanine deaminase
GDEase
Guanase
Guanine aminase
EC 3.5.4.3
Guanine aminohydrolase
GAH
NP_389200.1 (Protein)
NC_000964.3 (DNA/RNA sequence)
PF00383 (dCMP_cyt_deam_1)
[Graphical View]

KEGG enzyme name
Guanine deaminase
Guanase
Guanine aminase
GAH

UniprotKB: Accession Number Entry name Activity Subunit Subcellular location Cofactor
O34598 GUAD_BACSU Guanine + H(2)O = xanthine + NH(3). Zinc (By similarity).

KEGG Pathways
Map code Pathways E.C.
MAP00230 Purine metabolism

Compound table
Cofactors Substrates Products Intermediates
KEGG-id C00038 C00242 C00001 C00385 C00014 I00149
E.C.
Compound Zinc guanine H2O xanthine NH3 2-hydroxy-guanine
Type heavy metal amide group,amine group,aromatic ring (with nitrogen atoms) H2O amide group,aromatic ring (with nitrogen atoms) amine group,organic ion
ChEBI 29105
 29105
 		16235
 16235
 		15377
 15377
 		17712
 48517
 17712
 48517
 		16134
 16134
PubChem 32051
 32051
 		764
 764
 		22247451
 962
 22247451
 962
 		1188
 1188
 		222
 222
1tiyA00 Bound:_ZN Unbound Unbound Unbound Unbound
1tiyB00 Bound:_ZN Unbound Unbound Unbound Unbound
1wkqA00 Bound:_ZN Unbound Unbound Unbound Unbound
1wkqB00 Bound:_ZN Unbound Unbound Unbound Unbound

Reference for Active-site residues
resource references E.C.
PDB;1wkq & literature[5]

Active-site residues
PDB Catalytic residues Cofactor-binding residues Modified residues Main-chain involved in catalysis Comment
1tiyA00 GLU 55 HIS 53;CYS 83;CYS 86 GLU 81
1tiyB00 GLU 55 HIS 53;CYS 83;CYS 86 GLU 81
1wkqA00 GLU 55 HIS 53;CYS 83;CYS 86 GLU 81
1wkqB00 GLU 55 HIS 53;CYS 83;CYS 86 GLU 81

References for Catalytic Mechanism
References Sections No. of steps in catalysis
[4]
Scheme 1, p.35481-35483
[5]
Fig. 4, Fig. 6, p. 4200, p. 4203-4209

References
[1]
Resource
Comments
Medline ID
PubMed ID 8289286
Journal J Mol Biol
Year 1994
Volume 235
Pages 635-56
Authors Betts L, Xiang S, Short SA, Wolfenden R, Carter CW Jr
Title Cytidine deaminase. The 2.3 A crystal structure of an enzyme: transition-state analog complex.
Related PDB
Related UniProtKB
[2]
Resource
Comments
Medline ID
PubMed ID 11101664
Journal Microbiology
Year 2000
Volume 146 Pt 12
Pages 3061-9
Authors Nygaard P, Bested SM, Andersen KA, Saxild HH
Title Bacillus subtilis guanine deaminase is encoded by the yknA gene and is induced during growth with purines as the nitrogen source.
Related PDB
Related UniProtKB O34598
[3]
Resource
Comments
Medline ID
PubMed ID 12637534
Journal J Biol Chem
Year 2003
Volume 278
Pages 19111-7
Authors Ko TP, Lin JJ, Hu CY, Hsu YH, Wang AH, Liaw SH
Title Crystal structure of yeast cytosine deaminase. Insights into enzyme mechanism and evolution.
Related PDB
Related UniProtKB
[4]
Resource
Comments X-RAY CRYSTALLOGRAPHY (1.17 ANGSTROMS) IN COMPLEX WITH ZINC IONS.
Medline ID
PubMed ID 15180998
Journal J Biol Chem
Year 2004
Volume 279
Pages 35479-85
Authors Liaw SH, Chang YJ, Lai CT, Chang HC, Chang GG
Title Crystal structure of Bacillus subtilis guanine deaminase: the first domain-swapped structure in the cytidine deaminase superfamily.
Related PDB 1wkq
Related UniProtKB O34598
[5]
Resource
Comments
Medline ID
PubMed ID 17394305
Journal J Phys Chem B
Year 2007
Volume 111
Pages 4200-10
Authors Yao L, Cukier RI, Yan H
Title Catalytic mechanism of guanine deaminase: an ONIOM and molecular dynamics study.
Related PDB
Related UniProtKB
[6]
Resource
Comments
Medline ID
PubMed ID 17803218
Journal Proteins
Year 2008
Volume 70
Pages 873-81
Authors Fernandez JR, Welsh WJ, Firestein BL
Title Structural characterization of the zinc binding domain in cytosolic PSD-95 interactor (cypin): Role of zinc binding in guanine deamination and dendrite branching.
Related PDB
Related UniProtKB

Comments
This enzyme is homologous to cytidine deaminase (EC 3.5.4.5; D00406 in EzCatDB) and deoxycytidylate deaminase (EC 3.5.4.12; S00808 in EzCatDB), sharing a similar active site with them.
According to the literature [4], this enzyme seems to have a similar reaction mechanism to those by the homolgous enzymes. This enzyme catalyzes two successive reactions (rather than hydrolysis) as follows:

Created Updated
2008-07-04 2012-10-16