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Escherichia coli K-12 substr. MG1655 Transporter: ammonia / ammonium transporter



Gene: amtB Accession Numbers: EG11821 (EcoCyc), b0451, ECK0445

Synonyms: ybaG, AmtB ammonium Amt transporter

Regulation Summary Diagram: ?

Subunit composition of ammonia / ammonium transporter = [AmtB]3

Summary:
AmtB, a member of the Amt family of ammonium/ammonia transporters, is responsible for the bidirectional diffusion of ammonia/ammonium across the membrane and is necessary for growth only at low ammonium concentrations. Under nitrogen rich conditions transport of ammonia/ammonium by AmtB is blocked by the deuridylylated form of PII-2, the product of the glnK gene cotranscribed with amtB. The specific substrate of the AmtB transporter is controversial - it has been variously proposed that AmtB transports uncharged ammonia (NH3), cationic ammonium (NH4+) and that NH4+ deprotonation takes place at the periplasmic binding site prior to NH3 conduction through the pore (reviewed by [Winkler06]. Imported ammonium is rapidly metabolized to glutamine.

Disruption of the amtB gene impaired growth on ammonium only under acidic growth conditions, and this defect could be complemented by the cloned amtB gene [Soupene98]. Whole cell transport experiments have shown that AmtB mediates transport of the ammonium analogue, methylammonium, and have suggested that transport is dependent on rapid metabolism of the transported substrate [Soupene98]. AmtB mediates ammonium uniport in an energy independent, non-concentrative process [Soupene98, Javelle05], but homologues of AmtB in other organisms may function as ammonium/proton symporters [Siewe96].

The crystal structure has been resolved at 1.8 Å, 2.1 Å [Zheng04b], and 1.35 Å resolutions [Khademi04, Knepper04], as well as to 2.0 - 2.2 Å resolutions for 5 mutant variants [Javelle06]. A 12 Å resolution projection map of AmtB was determined by cryoelectron microscopy, and high-resolution topographs were acquired using atomic force microscopy [Conroy04]. AmtB has 11 membrane spanning segments and is trimeric in the native cell membrane [Blakey02]. AmtB has an ammonium binding site within the periplasmic vestibule [Liu06], a hydrophobic pore for ammonia conductance [Khademi04], and a cytoplasmic reprotonation site [Bostick07], though molecular dynamics simulations suggest the pore may also contain water raising the possibility of ammonium conductance as well [Lamoureux07]. Residues important in substrate binding, deprotonation and channel gating have been identified [Javelle08, Lin09]. Molecular dynamics simulations indicate that the AmtB pore is hydrophilic and may be occupied by both water and ammonia [Baday13].

Phosphatidylglycerol binding to AmtB results in increased stability of the protein structure as measured by its resistance to unfolding. X-ray crystallography of AmtB purified in the presence of phosphatidylglycerol suggested a distinct conformational change in a loop (residues 70-81) which constitutes a lipid binding site [Laganowsky14].

The amtB gene forms an operon with the glnK gene, and expression of this operon occurs under nitrogen-limiting conditions and is dependent on the NtrC regulatory protein [vanHeeswijk96]. GlnK and AmtB have been shown to quickly and reversibly interact after ammonium shock [Coutts02]. This reversible sequestration of GlnK by AmtB is rapidly responsive to μM concentrations of ammonia and requires the C-terminal cytoplasmic domain of AmtB [Coutts02]. The 1:1 interaction is dependent upon ATP and is sensitive to 2-oxoglutarate when MgCl2 is present [Durand06]. Deuridylylated GlnK is sequestered by AmtB; deuridylylated GlnK inhibits ammonium flux through AmtB by protein-protein interaction [Coutts02]. Deletion or mutation of amtB prevents deuridylylation of GlnK due to decreased intracellular glutamine levels - intracellular glutamine levels being the main effector of the uridyltransferase activity of GlnD. Deuridylylation of GlnK and subsequent GlnK-AmtB association is due to increased intracellular glutamine levels [Javelle04].

Crystal structures of the AmtB-GlnK complex have been determined to resolutions of 1.96 Å [Gruswitz07] and 2.5 Å [Conroy07]. A GlnK trimer, along with its associated 3 molecules of ADP, associates with the cytoplasmic face of the AmtB trimer by inserting the T-loop of each GlnK subunit into the cytoplasmic pore exit of the adjacent AmtB subunit [Conroy07].

E.coli amtB expressed in Xenopus oocytes is active as both a CO2 and NH3 channel [MusaAziz09].

Reviews: [Javelle05a, Winkler06]
Comment: [Knepper04]

Citations: [Li06d, Merrick06, Ludewig06, Lin06a, Luzhkov06, Nygaard06, Khademi06, Ishikita07, Tondervik06, Yang07b, Severi07, Wang13, Wang12a]

Locations: inner membrane

Map Position: [472,190 -> 473,476] (10.18 centisomes)
Length: 1287 bp / 428 aa

Molecular Weight of Polypeptide: 44.515 kD (from nucleotide sequence)

Unification Links: ASAP:ABE-0001564 , DIP:DIP-29874N , EchoBASE:EB1768 , EcoGene:EG11821 , EcoliWiki:b0451 , OU-Microarray:b0451 , PortEco:amtB , PR:PRO_000022100 , Pride:P69681 , Protein Model Portal:P69681 , RefSeq:NP_414985 , RegulonDB:EG11821 , SMR:P69681 , String:511145.b0451 , UniProt:P69681

Relationship Links: InterPro:IN-FAMILY:IPR001905 , InterPro:IN-FAMILY:IPR018047 , InterPro:IN-FAMILY:IPR024041 , Panther:IN-FAMILY:PTHR11730 , PDB:Structure:1U77 , PDB:Structure:1U7C , PDB:Structure:1U7G , PDB:Structure:1XQE , PDB:Structure:1XQF , PDB:Structure:2NMR , PDB:Structure:2NOP , PDB:Structure:2NOW , PDB:Structure:2NPC , PDB:Structure:2NPD , PDB:Structure:2NPE , PDB:Structure:2NPG , PDB:Structure:2NPJ , PDB:Structure:2NPK , PDB:Structure:2NS1 , PDB:Structure:2NUU , PDB:Structure:3C1G , PDB:Structure:3C1H , PDB:Structure:3C1I , PDB:Structure:3C1J , Pfam:IN-FAMILY:PF00909 , Prosite:IN-FAMILY:PS01219

Gene-Reaction Schematic: ?

Genetic Regulation Schematic: ?

GO Terms:

Biological Process: GO:0015670 - carbon dioxide transport Inferred from experiment [MusaAziz09]
GO:0015696 - ammonium transport Inferred from experiment Inferred by computational analysis [UniProtGOA11, GOA01, MusaAziz09, Soupene98]
GO:0006810 - transport Inferred by computational analysis [UniProtGOA11]
GO:0072488 - ammonium transmembrane transport Inferred by computational analysis [GOA01]
Molecular Function: GO:0008519 - ammonium transmembrane transporter activity Inferred from experiment Inferred by computational analysis [GOA01, MusaAziz09]
GO:0015292 - uniporter activity Inferred from experiment [Soupene98]
Cellular Component: GO:0005886 - plasma membrane Inferred from experiment Inferred by computational analysis [UniProtGOA11a, UniProtGOA11, DiazMejia09, Zhang07, Daley05]
GO:0005887 - integral component of plasma membrane Inferred from experiment [Thornton06]
GO:0016020 - membrane Inferred by computational analysis [UniProtGOA11, GOA01]
GO:0016021 - integral component of membrane Inferred by computational analysis [UniProtGOA11]

MultiFun Terms: cell structure membrane
transport Electrochemical potential driven transporters Porters (Uni-, Sym- and Antiporters)

Essentiality data for amtB 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]

Credits:
Created 11-Apr-2007 by Johnson A , TIGR
Curated 12-Oct-2007 by Johnson A , JCVI
Last-Curated ? 10-Jul-2014 by Mackie A , Macquarie University


Enzymatic reaction of: transport of ammonium (ammonia / ammonium transporter)

Alternative Substrates for ammonium: methylamine [Wang10 , Wang13 ]


Sequence Features

Feature Class Location Common Name Citations Comment
Signal-Sequence 1 -> 22  
[Khademi04, Thornton06]
 
Chain 23 -> 428  
[UniProt09]
UniProt: Ammonia channel;
Transmembrane-Region 29 -> 55  
[UniProt10a]
UniProt: Helical; Name=1;
Transmembrane-Region 29 -> 57 TM1
[Zheng04b]
 
Transmembrane-Region 60 -> 90  
[UniProt10a]
UniProt: Helical; Name=2;
Transmembrane-Region 64 -> 83 TM2a
[Zheng04b]
 
Transmembrane-Region 86 -> 90 TM2b
[Zheng04b]
 
Protein-Binding-Region 92 -> 103 phosphatidylglycerol binding site
[Laganowsky14]
 
Transmembrane-Region 119 -> 141 TM3
[Zheng04b]
 
Transmembrane-Region 147 -> 170 TM4
[Zheng04b]
 
Transmembrane-Region 185 -> 203  
[UniProt10a]
UniProt: Helical; Name=5;
Transmembrane-Region 190 -> 204 TM5
[Zheng04b]
 
Transmembrane-Region 216 -> 242  
[UniProt10a]
UniProt: Helical; Name=6;
Transmembrane-Region 220 -> 241 TM6
[Zheng04b]
 
Transmembrane-Region 246 -> 275  
[UniProt10a]
UniProt: Helical; Name=7;
Transmembrane-Region 247 -> 275 TM7
[Zheng04b]
 
Transmembrane-Region 280 -> 294  
[UniProt10a]
UniProt: Helical; Name=8;
Transmembrane-Region 282 -> 294 TM8
[Zheng04b]
 
Transmembrane-Region 303 -> 328  
[UniProt10a]
UniProt: Helical; Name=9;
Transmembrane-Region 311 -> 322 TM9
[Zheng04b]
 
Transmembrane-Region 333 -> 354  
[UniProt10a]
UniProt: Helical; Name=10;
Transmembrane-Region 336 -> 354 TM10
[Zheng04b]
 
Transmembrane-Region 370 -> 402  
[UniProt10a]
UniProt: Helical; Name=11;
Transmembrane-Region 371 -> 403 TM11
[Zheng04b]
 
Sequence-Conflict 377 -> 382  
[Naggert91, UniProt10a]
Alternate sequence: QLESIA → SWKASP; UniProt: (in Ref. 5);


Gene Local Context (not to scale): ?

Transcription Unit:

Notes:

History:
10/20/97 Gene b0451 from Blattner lab Genbank (v. M52) entry merged into EcoCyc gene EG11821; confirmed by SwissProt match.


References

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

Baday13: Baday S, Wang S, Lamoureux G, Berneche S (2013). "Different hydration patterns in the pores of AmtB and RhCG could determine their transport mechanisms." Biochemistry 52(40);7091-8. PMID: 24021113

Blakey02: Blakey D, Leech A, Thomas GH, Coutts G, Findlay K, Merrick M (2002). "Purification of the Escherichia coli ammonium transporter AmtB reveals a trimeric stoichiometry." Biochem J 364(Pt 2);527-35. PMID: 12023896

Bostick07: Bostick DL, Brooks CL (2007). "Deprotonation by dehydration: the origin of ammonium sensing in the AmtB channel." PLoS Comput Biol 3(2);e22. PMID: 17291160

Conroy04: Conroy MJ, Jamieson SJ, Blakey D, Kaufmann T, Engel A, Fotiadis D, Merrick M, Bullough PA (2004). "Electron and atomic force microscopy of the trimeric ammonium transporter AmtB." EMBO Rep 5(12);1153-8. PMID: 15568015

Conroy07: Conroy MJ, Durand A, Lupo D, Li XD, Bullough PA, Winkler FK, Merrick M (2007). "The crystal structure of the Escherichia coli AmtB-GlnK complex reveals how GlnK regulates the ammonia channel." Proc Natl Acad Sci U S A 104(4);1213-8. PMID: 17220269

Coutts02: Coutts G, Thomas G, Blakey D, Merrick M (2002). "Membrane sequestration of the signal transduction protein GlnK by the ammonium transporter AmtB." EMBO J 21(4);536-45. PMID: 11847102

Daley05: Daley DO, Rapp M, Granseth E, Melen K, Drew D, von Heijne G (2005). "Global topology analysis of the Escherichia coli inner membrane proteome." Science 308(5726);1321-3. PMID: 15919996

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

Durand06: Durand A, Merrick M (2006). "In vitro analysis of the Escherichia coli AmtB-GlnK complex reveals a stoichiometric interaction and sensitivity to ATP and 2-oxoglutarate." J Biol Chem 281(40);29558-67. PMID: 16864585

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."

Gruswitz07: Gruswitz F, O'Connell J, Stroud RM (2007). "Inhibitory complex of the transmembrane ammonia channel, AmtB, and the cytosolic regulatory protein, GlnK, at 1.96 A." Proc Natl Acad Sci U S A 104(1);42-7. PMID: 17190799

Ishikita07: Ishikita H, Knapp EW (2007). "Protonation states of ammonia/ammonium in the hydrophobic pore of ammonia transporter protein AmtB." J Am Chem Soc 129(5);1210-5. PMID: 17263403

Javelle04: Javelle A, Severi E, Thornton J, Merrick M (2004). "Ammonium sensing in Escherichia coli. Role of the ammonium transporter AmtB and AmtB-GlnK complex formation." J Biol Chem 279(10);8530-8. PMID: 14668330

Javelle05: Javelle A, Thomas G, Marini AM, Kramer R, Merrick M (2005). "In vivo functional characterization of the Escherichia coli ammonium channel AmtB: evidence for metabolic coupling of AmtB to glutamine synthetase." Biochem J 390(Pt 1);215-22. PMID: 15876187

Javelle05a: Javelle A, Merrick M (2005). "Complex formation between AmtB and GlnK: an ancestral role in prokaryotic nitrogen control." Biochem Soc Trans 33(Pt 1);170-2. PMID: 15667297

Javelle06: Javelle A, Lupo D, Zheng L, Li XD, Winkler FK, Merrick M (2006). "An unusual twin-his arrangement in the pore of ammonia channels is essential for substrate conductance." J Biol Chem 281(51);39492-8. PMID: 17040913

Javelle08: Javelle A, Lupo D, Ripoche P, Fulford T, Merrick M, Winkler FK (2008). "Substrate binding, deprotonation, and selectivity at the periplasmic entrance of the Escherichia coli ammonia channel AmtB." Proc Natl Acad Sci U S A 105(13);5040-5. PMID: 18362341

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

Khademi04: Khademi S, O'Connell J, Remis J, Robles-Colmenares Y, Miercke LJ, Stroud RM (2004). "Mechanism of ammonia transport by Amt/MEP/Rh: structure of AmtB at 1.35 A." Science 305(5690);1587-94. PMID: 15361618

Khademi06: Khademi S, Stroud RM (2006). "The Amt/MEP/Rh family: structure of AmtB and the mechanism of ammonia gas conduction." Physiology (Bethesda) 21;419-29. PMID: 17119155

Knepper04: Knepper MA, Agre P (2004). "Structural biology. The atomic architecture of a gas channel." Science 305(5690);1573-4. PMID: 15361612

Laganowsky14: Laganowsky A, Reading E, Allison TM, Ulmschneider MB, Degiacomi MT, Baldwin AJ, Robinson CV (2014). "Membrane proteins bind lipids selectively to modulate their structure and function." Nature 510(7503);172-5. PMID: 24899312

Lamoureux07: Lamoureux G, Klein ML, Berneche S (2007). "A stable water chain in the hydrophobic pore of the AmtB ammonium transporter." Biophys J 92(9);L82-4. PMID: 17351012

Li06d: Li XD, Lupo D, Zheng L, Winkler F (2006). "Structural and functional insights into the AmtB/Mep/Rh protein family." Transfus Clin Biol 13(1-2);65-9. PMID: 16564194

Lin06a: Lin Y, Cao Z, Mo Y (2006). "Molecular dynamics simulations on the Escherichia coli ammonia channel protein AmtB: mechanism of ammonia/ammonium transport." J Am Chem Soc 128(33);10876-84. PMID: 16910683

Lin09: Lin Y, Cao Z, Mo Y (2009). "Functional role of Asp160 and the deprotonation mechanism of ammonium in the Escherichia coli ammonia channel protein AmtB." J Phys Chem B 113(14);4922-9. PMID: 19278252

Liu06: Liu Y, Hu X (2006). "Molecular determinants for binding of ammonium ion in the ammonia transporter AmtB-A quantum chemical analysis." J Phys Chem A Mol Spectrosc Kinet Environ Gen Theory 110(4);1375-81. PMID: 16435797

Ludewig06: Ludewig U (2006). "Ion transport versus gas conduction: function of AMT/Rh-type proteins." Transfus Clin Biol 13(1-2);111-6. PMID: 16563830

Luzhkov06: Luzhkov VB, Almlof M, Nervall M, Aqvist J (2006). "Computational study of the binding affinity and selectivity of the bacterial ammonium transporter AmtB." Biochemistry 45(36);10807-14. PMID: 16953566

Merrick06: Merrick M, Javelle A, Durand A, Severi E, Thornton J, Avent ND, Conroy MJ, Bullough PA (2006). "The Escherichia coli AmtB protein as a model system for understanding ammonium transport by Amt and Rh proteins." Transfus Clin Biol 13(1-2);97-102. PMID: 16563828

MusaAziz09: Musa-Aziz R, Chen LM, Pelletier MF, Boron WF (2009). "Relative CO2/NH3 selectivities of AQP1, AQP4, AQP5, AmtB, and RhAG." Proc Natl Acad Sci U S A 106(13);5406-11. PMID: 19273840

Naggert91: Naggert J, Narasimhan ML, DeVeaux L, Cho H, Randhawa ZI, Cronan JE, Green BN, Smith S (1991). "Cloning, sequencing, and characterization of Escherichia coli thioesterase II." J Biol Chem 1991;266(17);11044-50. PMID: 1645722

Nygaard06: Nygaard TP, Rovira C, Peters GH, Jensen MO (2006). "Ammonium recruitment and ammonia transport by E. coli ammonia channel AmtB." Biophys J 91(12);4401-12. PMID: 17012311

Severi07: Severi E, Javelle A, Merrick M (2007). "The conserved carboxy-terminal region of the ammonia channel AmtB plays a critical role in channel function." Mol Membr Biol 24(2);161-71. PMID: 17453422

Siewe96: Siewe RM, Weil B, Burkovski A, Eikmanns BJ, Eikmanns M, Kramer R (1996). "Functional and genetic characterization of the (methyl)ammonium uptake carrier of Corynebacterium glutamicum." J Biol Chem 1996;271(10);5398-403. PMID: 8621394

Soupene98: Soupene E, He L, Yan D, Kustu S (1998). "Ammonia acquisition in enteric bacteria: physiological role of the ammonium/methylammonium transport B (AmtB) protein." Proc Natl Acad Sci U S A 1998;95(12);7030-4. PMID: 9618533

Stevenson77: Stevenson R, Silver S (1977). "Methylammonium uptake by Escherichia coli: evidence for a bacterial NH4+ transport system." Biochem Biophys Res Commun 75(4);1133-9. PMID: 16600

Thornton06: Thornton J, Blakey D, Scanlon E, Merrick M (2006). "The ammonia channel protein AmtB from Escherichia coli is a polytopic membrane protein with a cleavable signal peptide." FEMS Microbiol Lett 258(1);114-20. PMID: 16630265

Tondervik06: Tondervik A, Torgersen HR, Botnmark HK, Strom AR (2006). "Transposon mutations in the 5' end of glnD, the gene for a nitrogen regulatory sensor, that suppress the osmosensitive phenotype caused by otsBA lesions in Escherichia coli." J Bacteriol 188(12);4218-26. PMID: 16740928

UniProt09: UniProt Consortium (2009). "UniProt version 15.8 released on 2009-10-01 00:00:00." Database.

UniProt10a: UniProt Consortium (2010). "UniProt version 2010-11 released on 2010-11-02 00:00:00." Database.

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

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

vanHeeswijk96: van Heeswijk WC, Hoving S, Molenaar D, Stegeman B, Kahn D, Westerhoff HV (1996). "An alternative PII protein in the regulation of glutamine synthetase in Escherichia coli." Mol Microbiol 1996;21(1);133-46. PMID: 8843440

Wang10: Wang J, Yang H, Zuo Z, Yan X, Wang Y, Luo X, Jiang H, Chen K, Zhu W (2010). "Molecular dynamics simulations on the mechanism of transporting methylamine and ammonia by ammonium transporter AmtB." J Phys Chem B 114(46);15172-9. PMID: 20973592

Wang12a: Wang S, Orabi EA, Baday S, Berneche S, Lamoureux G (2012). "Ammonium transporters achieve charge transfer by fragmenting their substrate." J Am Chem Soc 134(25);10419-27. PMID: 22631217

Wang13: Wang J, Fulford T, Shao Q, Javelle A, Yang H, Zhu W, Merrick M (2013). "Ammonium transport proteins with changes in one of the conserved pore histidines have different performance in ammonia and methylamine conduction." PLoS One 8(5);e62745. PMID: 23667517

Winkler06: Winkler FK (2006). "Amt/MEP/Rh proteins conduct ammonia." Pflugers Arch 451(6);701-7. PMID: 16273393

Yang07b: Yang H, Xu Y, Zhu W, Chen K, Jiang H (2007). "Detailed mechanism for AmtB conducting NH4+/NH3: molecular dynamics simulations." Biophys J 92(3);877-85. PMID: 17098799

Zhang07: Zhang N, Chen R, Young N, Wishart D, Winter P, Weiner JH, Li L (2007). "Comparison of SDS- and methanol-assisted protein solubilization and digestion methods for Escherichia coli membrane proteome analysis by 2-D LC-MS/MS." Proteomics 7(4);484-93. PMID: 17309111

Zheng04b: Zheng L, Kostrewa D, Berneche S, Winkler FK, Li XD (2004). "The mechanism of ammonia transport based on the crystal structure of AmtB of Escherichia coli." Proc Natl Acad Sci U S A 101(49):17090-5. PMID: 15563598

Other References Related to Gene Regulation

Barrios99: Barrios H, Valderrama B, Morett E (1999). "Compilation and analysis of sigma(54)-dependent promoter sequences." Nucleic Acids Res 27(22);4305-13. PMID: 10536136

Hommais04: Hommais F, Krin E, Coppee JY, Lacroix C, Yeramian E, Danchin A, Bertin P (2004). "GadE (YhiE): a novel activator involved in the response to acid environment in Escherichia coli." Microbiology 150(Pt 1);61-72. PMID: 14702398

Kumar11: Kumar R, Shimizu K (2011). "Transcriptional regulation of main metabolic pathways of cyoA, cydB, fnr, and fur gene knockout Escherichia coli in C-limited and N-limited aerobic continuous cultures." Microb Cell Fact 10;3. PMID: 21272324

Reitzer01: Reitzer L, Schneider BL (2001). "Metabolic context and possible physiological themes of sigma(54)-dependent genes in Escherichia coli." Microbiol Mol Biol Rev 65(3);422-44, table of contents. PMID: 11528004


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Please cite the following article in publications resulting from the use of EcoCyc: Nucleic Acids Research 41:D605-12 2013
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