Escherichia coli K-12 substr. MG1655 Enzyme: adenosine-3'(2'),5'-bisphosphate nucleotidase

Gene: cysQ Accession Numbers: EG10043 (EcoCyc), b4214, ECK4210

Synonyms: amt, amtA

Regulation Summary Diagram: ?

Regulation summary diagram for cysQ

CysQ is an adenosine-3',5'-bisphosphate nucleotidase which recycles adenosine-3',5'-bisphosphate (PAP) that is generated during sulfate assimilation (see sulfate reduction I (assimilatory)) and holo-ACP synthesis for the biosynthesis of fatty acids (see holo-[acyl-carrier-protein] synthase and holo-[acyl carrier protein] synthase 2). CysQ is inhibited by Li+, and the enzyme is the main target for lithium toxicity in E. coli [Mechold06]. The protein is similar to SuhB and mammalian inositol monophosphatase [Neuwald92].

cysQ mutants require cysteine or sulfite to grow under aerobic conditions, though they continue to carry out normal uptake of sulfate [Neuwald92]. A cysQ mutation can be complemented with the rice gene RHL, which encodes an enzyme catalyzing the conversion of adenosine 3'-phosphate 5'-phosphosulfate (PAPS) to adenosine 5'-phosphosulfate (APS) [Peng95]. The cysQ mutant phenotype is likely due to inhibition of 3'-phospho-adenylylsulfate reductase by accumulating adenosine-3',5'-bisphosphate.

CysQ was initially identified as a putative ammonium transporter [Jayakumar89, Jayakumar91, Fabiny91]. This functional assignment was later shown to be incorrect [Neuwald92].

CysQ is found in the inner membrane fraction [LopezCampistrou05].

Locations: inner membrane, cytosol

Map Position: [4,434,778 -> 4,435,518] (95.58 centisomes, 344°)
Length: 741 bp / 246 aa

Molecular Weight of Polypeptide: 27.176 kD (from nucleotide sequence), 28.0 kD (experimental) [Fukuda07 ]

Unification Links: ASAP:ABE-0013786 , CGSC:34409 , DIP:DIP-9385N , EchoBASE:EB0041 , EcoGene:EG10043 , EcoliWiki:b4214 , Mint:MINT-1300047 , ModBase:P22255 , OU-Microarray:b4214 , PortEco:cysQ , PR:PRO_000022386 , Pride:P22255 , Protein Model Portal:P22255 , RefSeq:NP_418635 , RegulonDB:EG10043 , SMR:P22255 , String:511145.b4214 , UniProt:P22255

Relationship Links: InterPro:IN-FAMILY:IPR000760 , InterPro:IN-FAMILY:IPR006240 , InterPro:IN-FAMILY:IPR020550 , InterPro:IN-FAMILY:IPR020583 , Panther:IN-FAMILY:PTHR20854 , Pfam:IN-FAMILY:PF00459 , Prosite:IN-FAMILY:PS00629 , Prosite:IN-FAMILY:PS00630

In Paralogous Gene Group: 580 (2 members)

Gene-Reaction Schematic: ?

Gene-Reaction Schematic

GO Terms:

Biological Process: GO:0000103 - sulfate assimilation Inferred from experiment [Neuwald92]
GO:0016311 - dephosphorylation Inferred from experiment Inferred by computational analysis [GOA01, Mechold06]
GO:0046854 - phosphatidylinositol phosphorylation Inferred by computational analysis [GOA01a]
Molecular Function: GO:0000287 - magnesium ion binding Inferred from experiment Inferred by computational analysis [GOA01a, Mechold06]
GO:0008441 - 3'(2'),5'-bisphosphate nucleotidase activity Inferred from experiment Inferred by computational analysis [GOA01, Mechold06]
GO:0016787 - hydrolase activity Inferred by computational analysis [UniProtGOA11a]
GO:0046872 - metal ion binding Inferred by computational analysis [UniProtGOA11a]
Cellular Component: GO:0005737 - cytoplasm Inferred by computational analysis [UniProtGOA11, UniProtGOA11a]
GO:0005886 - plasma membrane Inferred by computational analysis [UniProtGOA11, UniProtGOA11a]
GO:0016020 - membrane Inferred by computational analysis [UniProtGOA11a, GOA01a]

MultiFun Terms: metabolism biosynthesis of building blocks fatty acids and phosphatidic acid
metabolism metabolism of other compounds sulfur metabolism

Essentiality data for cysQ 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 No 37 Aerobic 7.2 0.35 No [Joyce06]
MOPS medium with 0.4% glucose Yes 37 Aerobic 7.2 0.22 Yes [Baba06, Comment 2]

Curated 01-Feb-2006 by Shearer A , SRI International
Last-Curated ? 15-Jul-2008 by Keseler I , SRI International

Enzymatic reaction of: adenosine-3'(2'),5'-bisphosphate nucleotidase

EC Number:

adenosine 3',5'-bisphosphate + H2O <=> AMP + phosphate

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction in which it was curated.

The reaction is physiologically favored in the direction shown.

Alternative Substrates for adenosine 3',5'-bisphosphate: adenosine-2',5'-bisphosphate [Fukuda07 ]

The enzyme catalyzes hydrolysis of inositol 1,4-bisphosphate with 1000-fold lower catalytic efficiency [Spiegelberg99]. A range of possible substrates was tested in [Fukuda07].

Cofactors or Prosthetic Groups: Mg2+ [Mechold06]

Inhibitors (Unknown Mechanism): Li+ [Mechold06] , Ca2+ [Mechold06]

Kinetic Parameters:

Km (μM)
kcat (sec-1)
kcat/Km (sec-1 μM-1)
adenosine 3',5'-bisphosphate
[Fukuda07, BRENDA14]

pH(opt): 6.4 [Fukuda07]

Sequence Features

Protein sequence of adenosine-3'(2'),5'-bisphosphate nucleotidase with features indicated

Feature Class Location Citations Comment
Metal-Binding-Site 64
UniProt: Magnesium 1; Non-Experimental Qualifier: by similarity;
Metal-Binding-Site 83
UniProt: Magnesium 1; Non-Experimental Qualifier: by similarity;
Metal-Binding-Site 85
UniProt: Magnesium 1; via carbonyl oxygen; Non-Experimental Qualifier: by similarity;
Protein-Segment 85 -> 88
UniProt: Substrate binding; Sequence Annotation Type: region of interest; Non-Experimental Qualifier: by similarity;
Metal-Binding-Site 86
UniProt: Magnesium 2; Non-Experimental Qualifier: by similarity;
Sequence-Conflict 193 -> 194
[Neuwald92, Fabiny91, UniProt10]
UniProt: (in Ref. 1 and 2);
Metal-Binding-Site 205
UniProt: Magnesium 2; Non-Experimental Qualifier: by similarity;

Gene Local Context (not to scale): ?

Gene local context diagram

Transcription Unit:

Transcription-unit diagram


10/20/97 Gene b4214 from Blattner lab Genbank (v. M52) entry merged into EcoCyc gene EG10043; confirmed by SwissProt match.


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."

Fabiny91: Fabiny JM, Jayakumar A, Chinault AC, Barnes EM (1991). "Ammonium transport in Escherichia coli: localization and nucleotide sequence of the amtA gene." J Gen Microbiol 137(4);983-9. PMID: 1856684

Fukuda07: Fukuda C, Kawai S, Murata K (2007). "NADP(H) phosphatase activities of archaeal inositol monophosphatase and eubacterial 3'-phosphoadenosine 5'-phosphate phosphatase." Appl Environ Microbiol 73(17);5447-52. PMID: 17616624

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

GOA01a: GOA, DDB, FB, MGI, ZFIN (2001). "Gene Ontology annotation through association of InterPro records with GO terms."

Jayakumar89: Jayakumar A, Hwang SJ, Fabiny JM, Chinault AC, Barnes EM (1989). "Isolation of an ammonium or methylammonium ion transport mutant of Escherichia coli and complementation by the cloned gene." J Bacteriol 171(2);996-1001. PMID: 2536689

Jayakumar91: Jayakumar A, Rudd KE, Fabiny JM, Barnes EM (1991). "Localization of the Escherichia coli amtA gene to 95.8 minutes." J Bacteriol 173(5);1572-3. PMID: 1999381

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

LopezCampistrou05: Lopez-Campistrous A, Semchuk P, Burke L, Palmer-Stone T, Brokx SJ, Broderick G, Bottorff D, Bolch S, Weiner JH, Ellison MJ (2005). "Localization, annotation, and comparison of the Escherichia coli K-12 proteome under two states of growth." Mol Cell Proteomics 4(8);1205-9. PMID: 15911532

Mechold06: Mechold U, Ogryzko V, Ngo S, Danchin A (2006). "Oligoribonuclease is a common downstream target of lithium-induced pAp accumulation in Escherichia coli and human cells." Nucleic Acids Res 34(8);2364-73. PMID: 16682444

Neuwald92: Neuwald AF, Krishnan BR, Brikun I, Kulakauskas S, Suziedelis K, Tomcsanyi T, Leyh TS, Berg DE (1992). "cysQ, a gene needed for cysteine synthesis in Escherichia coli K-12 only during aerobic growth." J Bacteriol 1992;174(2);415-25. PMID: 1729235

Peng95: Peng Z, Verma DP (1995). "A rice HAL2-like gene encodes a Ca(2+)-sensitive 3'(2'),5'-diphosphonucleoside 3'(2')-phosphohydrolase and complements yeast met22 and Escherichia coli cysQ mutations." J Biol Chem 270(49);29105-10. PMID: 7493934

Spiegelberg99: Spiegelberg BD, Xiong JP, Smith JJ, Gu RF, York JD (1999). "Cloning and characterization of a mammalian lithium-sensitive bisphosphate 3'-nucleotidase inhibited by inositol 1,4-bisphosphate." J Biol Chem 274(19);13619-28. PMID: 10224133

UniProt10: UniProt Consortium (2010). "UniProt version 2010-11 released on 2010-11-02 00:00:00." Database.

UniProt10a: 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 the manual assignment of UniProtKB Subcellular Location terms in UniProtKB/Swiss-Prot entries."

UniProtGOA11a: UniProt-GOA (2011). "Gene Ontology annotation based on manual assignment of UniProtKB keywords in UniProtKB/Swiss-Prot entries."

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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 Tue Oct 13, 2015, biocyc13.