Escherichia coli K-12 substr. MG1655 Enzyme: guanine deaminase

Gene: guaD Accession Numbers: G7502 (EcoCyc), b2883, ECK2879

Synonyms: ygfP

Regulation Summary Diagram: ?

Regulation summary diagram for guaD

Guanine deaminase is an aminohydrolase that converts guanine to xanthine and ammonia. This reaction removes guanine from the pool of guanine-containing metabolites, which helps to regulate cellular GTP and the guanylate nucleotide pool.

Ammeline is an intermediate in the metabolism of melamine (see the MetaCyc pathway for melamine degradation). E. coli is able to metabolize ammeline to ammelide, but does not metabolize either melamine or ammelide. A guaD deletion mutant is deficient in ammeline deaminase activity [Seffernick10].

Locations: cytosol

Map Position: [3,023,788 -> 3,025,107] (65.17 centisomes, 235°)
Length: 1320 bp / 439 aa

Molecular Weight of Polypeptide: 50.244 kD (from nucleotide sequence)

Unification Links: ASAP:ABE-0009465 , EchoBASE:EB2878 , EcoGene:EG13066 , EcoliWiki:b2883 , Entrez-gene:947366 , ModBase:P76641 , OU-Microarray:b2883 , PortEco:guaD , Pride:P76641 , Protein Model Portal:P76641 , RefSeq:NP_417359 , RegulonDB:G7502 , SMR:P76641 , String:511145.b2883 , UniProt:P76641

Relationship Links: InterPro:IN-FAMILY:IPR006680 , InterPro:IN-FAMILY:IPR011059 , InterPro:IN-FAMILY:IPR014311 , Panther:IN-FAMILY:PTHR11271:SF6 , Pfam:IN-FAMILY:PF01979

Gene-Reaction Schematic: ?

Gene-Reaction Schematic

GO Terms:

Biological Process: GO:0006147 - guanine catabolic process Inferred by computational analysis [UniProtGOA12, GOA01]
Molecular Function: GO:0008270 - zinc ion binding Inferred from experiment Inferred by computational analysis [GOA01, Maynes00]
GO:0008892 - guanine deaminase activity Inferred from experiment Inferred by computational analysis [GOA01a, GOA01, Maynes00]
GO:0018756 - ammeline aminohydrolase activity Inferred from experiment [Seffernick10]
GO:0016787 - hydrolase activity Inferred by computational analysis [UniProtGOA11, GOA01]
GO:0016810 - hydrolase activity, acting on carbon-nitrogen (but not peptide) bonds Inferred by computational analysis [GOA01]
GO:0046872 - metal ion binding Inferred by computational analysis [UniProtGOA11]
Cellular Component: GO:0005829 - cytosol Inferred by computational analysis [DiazMejia09]

MultiFun Terms: metabolism central intermediary metabolism

Essentiality data for guaD knockouts: ?

Growth Medium Growth? T (°C) O2 pH Osm/L Growth Observations
LB enriched Yes 37 Aerobic 6.95   Yes [Gerdes03, Comment 1]
LB Lennox Yes 37 Aerobic 7   Yes [Baba06, Comment 2]
M9 medium with 1% glycerol Yes 37 Aerobic 7.2 0.35 Yes [Joyce06, Comment 3]
MOPS medium with 0.4% glucose Yes 37 Aerobic 7.2 0.22 Yes [Baba06, Comment 2]
Yes [Feist07, Comment 4]

Last-Curated ? 28-Dec-2009 by Keseler I , SRI International
Reviewed 07-Feb-2010 by Sarker M

Enzymatic reaction of: guanine deaminase

Synonyms: guanase, guanine aminase, guanine aminohydrolase

EC Number:

guanine + H+ + H2O <=> ammonium + xanthine

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.

The reaction is favored in the direction shown.

In Pathways: guanosine nucleotides degradation III

Enzyme activity requires a divalent cation (Zn2+ or Mn2+) [Maynes00].

Cofactors or Prosthetic Groups: Zn2+ [Comment 5, Maynes00]

Inhibitors (Unknown Mechanism): o-phenanthroline [Maynes00]

Kinetic Parameters:

Km (μM)
[Maynes00, BRENDA14]

Sequence Features

Protein sequence of guanine deaminase with features indicated

Feature Class Location Citations Comment
Metal-Binding-Site 82
UniProt: Zinc; via tele nitrogen; Non-Experimental Qualifier: by similarity;
Metal-Binding-Site 84
UniProt: Zinc; via tele nitrogen; Non-Experimental Qualifier: by similarity;
Amino-Acid-Sites-That-Bind 87
UniProt: Substrate; Non-Experimental Qualifier: by similarity;
Amino-Acid-Sites-That-Bind 209
UniProt: Substrate; Non-Experimental Qualifier: by similarity;
Metal-Binding-Site 237
UniProt: Zinc; via tele nitrogen; Non-Experimental Qualifier: by similarity;
Amino-Acid-Sites-That-Bind 240
UniProt: Substrate; Non-Experimental Qualifier: by similarity;
Amino-Acid-Sites-That-Bind 276
UniProt: Substrate; Non-Experimental Qualifier: by similarity;
Metal-Binding-Site 327
UniProt: Zinc; Non-Experimental Qualifier: by similarity;

Gene Local Context (not to scale): ?

Gene local context diagram

Transcription Unit:

Transcription-unit diagram


Markus Krummenacker on Tue Oct 14, 1997:
Gene object created from Blattner lab Genbank (v. M52) entry.


Baba06: Baba T, Ara T, Hasegawa M, Takai Y, Okumura Y, Baba M, Datsenko KA, Tomita M, Wanner BL, Mori H (2006). "Construction of Escherichia coli K-12 in-frame, single-gene knockout mutants: the Keio collection." Mol Syst Biol 2;2006.0008. PMID: 16738554

BRENDA14: BRENDA team (2014). "Imported from BRENDA version existing on Aug 2014."

DiazMejia09: Diaz-Mejia JJ, Babu M, Emili A (2009). "Computational and experimental approaches to chart the Escherichia coli cell-envelope-associated proteome and interactome." FEMS Microbiol Rev 33(1);66-97. PMID: 19054114

Feist07: Feist AM, Henry CS, Reed JL, Krummenacker M, Joyce AR, Karp PD, Broadbelt LJ, Hatzimanikatis V, Palsson BO (2007). "A genome-scale metabolic reconstruction for Escherichia coli K-12 MG1655 that accounts for 1260 ORFs and thermodynamic information." Mol Syst Biol 3;121. PMID: 17593909

Gerdes03: Gerdes SY, Scholle MD, Campbell JW, Balazsi G, Ravasz E, Daugherty MD, Somera AL, Kyrpides NC, Anderson I, Gelfand MS, Bhattacharya A, Kapatral V, D'Souza M, Baev MV, Grechkin Y, Mseeh F, Fonstein MY, Overbeek R, Barabasi AL, Oltvai ZN, Osterman AL (2003). "Experimental determination and system level analysis of essential genes in Escherichia coli MG1655." J Bacteriol 185(19);5673-84. PMID: 13129938

GOA01: GOA, DDB, FB, MGI, ZFIN (2001). "Gene Ontology annotation through association of InterPro records with GO terms."

GOA01a: GOA, MGI (2001). "Gene Ontology annotation based on Enzyme Commission mapping." Genomics 74;121-128.

Joyce06: Joyce AR, Reed JL, White A, Edwards R, Osterman A, Baba T, Mori H, Lesely SA, Palsson BO, Agarwalla S (2006). "Experimental and computational assessment of conditionally essential genes in Escherichia coli." J Bacteriol 188(23);8259-71. PMID: 17012394

Maynes00: Maynes JT, Yuan RG, Snyder FF (2000). "Identification, expression, and characterization of Escherichia coli guanine deaminase." J Bacteriol 182(16);4658-60. PMID: 10913105

Seffernick10: Seffernick JL, Dodge AG, Sadowsky MJ, Bumpus JA, Wackett LP (2010). "Bacterial ammeline metabolism via guanine deaminase." J Bacteriol 192:1106-12. PMID: 20023034

UniProt10: UniProt Consortium (2010). "UniProt version 2010-07 released on 2010-06-15 00:00:00." Database.

UniProtGOA11: UniProt-GOA (2011). "Gene Ontology annotation based on manual assignment of UniProtKB keywords in UniProtKB/Swiss-Prot entries."

UniProtGOA12: UniProt-GOA (2012). "Gene Ontology annotation based on UniPathway vocabulary mapping."

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Please cite the following article in publications resulting from the use of EcoCyc: Nucleic Acids Research 41:D605-12 2013
Page generated by SRI International Pathway Tools version 19.0 on Thu Oct 8, 2015, biocyc14.