Gene Symbol: glnK
Description: nitrogen assimilation regulatory protein for GlnL, GlnE, and AmtB
Alias: ECK0444, JW0440, ybaI
Species: Escherichia coli str. K-12 substr. MG1655

Top Publications

  1. Atkinson M, Ninfa A. Characterization of the GlnK protein of Escherichia coli. Mol Microbiol. 1999;32:301-13 pubmed
    The GlnK and PII signal transduction proteins are paralogues that play distinct roles in nitrogen regulation...
  2. Forchhammer K, Hedler A, Strobel H, Weiss V. Heterotrimerization of PII-like signalling proteins: implications for PII-mediated signal transduction systems. Mol Microbiol. 1999;33:338-49 pubmed
    ..coli PII paralogues GlnB and GlnK. This led to the discovery that GlnK and GlnB of E. coli also form heterotrimers with each other...
  3. van Heeswijk W, Molenaar D, Hoving S, Westerhoff H. The pivotal regulator GlnB of Escherichia coli is engaged in subtle and context-dependent control. FEBS J. 2009;276:3324-40 pubmed publisher
    ..Neither glnB expression nor P(II)* (i.e. the sum of the concentration of the P(II)-like proteins GlnB and GlnK) had control over the steady-state adenylylation level of GS when cells were grown in the presence of ammonia, in ..
  4. Javelle A, Merrick M. Complex formation between AmtB and GlnK: an ancestral role in prokaryotic nitrogen control. Biochem Soc Trans. 2005;33:170-2 pubmed
    ..In Escherichia coli, the AmtB protein and the associated P(II) signal transduction protein (GlnK) have recently been recognized as an ammonium sensory system that effectively couples the intracellular nitrogen ..
  5. Maheswaran M, Forchhammer K. Carbon-source-dependent nitrogen regulation in Escherichia coli is mediated through glutamine-dependent GlnB signalling. Microbiology. 2003;149:2163-72 pubmed
    The P(II) signal transduction proteins GlnB and GlnK are uridylylated/deuridylylated in response to the intracellular glutamine level, the primary signal of the cellular nitrogen status...
  6. Reitzer L. Nitrogen assimilation and global regulation in Escherichia coli. Annu Rev Microbiol. 2003;57:155-76 pubmed
    ..Guanosine tetraphosphate appears to control Lrp synthesis. In summary, a network of interacting global regulators that senses different aspects of metabolism integrates nitrogen assimilation with other metabolic processes. ..
  7. Gruswitz F, O Connell J, Stroud R. 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. 2007;104:42-7 pubmed
    Ammonia conductance is highly regulated. A P(II) signal transduction protein, GlnK, is the final regulator of transmembrane ammonia conductance by the ammonia channel AmtB in Escherichia coli...
  8. van Heeswijk W, Wen D, Clancy P, Jaggi R, Ollis D, Westerhoff H, et al. The Escherichia coli signal transducers PII (GlnB) and GlnK form heterotrimers in vivo: fine tuning the nitrogen signal cascade. Proc Natl Acad Sci U S A. 2000;97:3942-7 pubmed
    ..Through these two routes, PII regulates both amount and activity of glutamine synthetase. GlnK is the recently discovered paralogue of PII, with a similar trimeric x-ray structure...
  9. Boogerd F, Ma H, Bruggeman F, van Heeswijk W, García Contreras R, Molenaar D, et al. AmtB-mediated NH3 transport in prokaryotes must be active and as a consequence regulation of transport by GlnK is mandatory to limit futile cycling of NH4(+)/NH3. FEBS Lett. 2011;585:23-8 pubmed publisher
    ..We hypothesize that the regulatory protein GlnK is required to fine-tune the active transport of ammonium in order to limit futile cycling whilst enabling an ..

More Information


  1. Radchenko M, Thornton J, Merrick M. P(II) signal transduction proteins are ATPases whose activity is regulated by 2-oxoglutarate. Proc Natl Acad Sci U S A. 2013;110:12948-53 pubmed publisher
    ..We have now shown that the Escherichia coli P(II) protein, GlnK, has an ATPase activity that is inhibited by 2-OG...
  2. van Heeswijk W, Hoving S, Molenaar D, Stegeman B, Kahn D, Westerhoff H. An alternative PII protein in the regulation of glutamine synthetase in Escherichia coli. Mol Microbiol. 1996;21:133-46 pubmed
    ..We describe a new operon, glnK amtB, which encodes a homologue of PII and a putative ammonia transporter...
  3. Allikmets R, Gerrard B, Court D, Dean M. Cloning and organization of the abc and mdl genes of Escherichia coli: relationship to eukaryotic multidrug resistance. Gene. 1993;136:231-6 pubmed
    ..9 of the chromosome, encodes a single ATP-binding domain, and is most homologous to ftsE, a cell division control gene of E. coli. The abc gene product also shows aa sequence homology to several E. coli permeases...
  4. Conroy M, Durand A, Lupo D, Li X, Bullough P, Winkler F, et al. The crystal structure of the Escherichia coli AmtB-GlnK complex reveals how GlnK regulates the ammonia channel. Proc Natl Acad Sci U S A. 2007;104:1213-8 pubmed
    ..In Escherichia coli, previous studies have indicated that binding of the PII signal transduction protein GlnK to the ammonia channel AmtB regulates the channel thereby controlling ammonium influx in response to the ..
  5. Atkinson M, Blauwkamp T, Ninfa A. Context-dependent functions of the PII and GlnK signal transduction proteins in Escherichia coli. J Bacteriol. 2002;184:5364-75 pubmed
    Two closely related signal transduction proteins, PII and GlnK, have distinct physiological roles in the regulation of nitrogen assimilation...
  6. van Heeswijk W, Stegeman B, Hoving S, Molenaar D, Kahn D, Westerhoff H. An additional PII in Escherichia coli: a new regulatory protein in the glutamine synthetase cascade. FEMS Microbiol Lett. 1995;132:153-7 pubmed
    ..coli PII. It contains the conserved tyrosine residue which is known to be the site of uridylylation in PII. E. coli is the first organism in which two different PII proteins have been detected. ..
  7. Atkinson M, Ninfa A. Role of the GlnK signal transduction protein in the regulation of nitrogen assimilation in Escherichia coli. Mol Microbiol. 1998;29:431-47 pubmed
    Two structurally similar but functionally distinct PII-like proteins, PII and GlnK, regulate nitrogen assimilation in Escherichia coli...
  8. Tøndervik A, Torgersen H, Botnmark H, Strøm A. 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. 2006;188:4218-26 pubmed
    ..g., the glnK-amtB operon...
  9. Gosztolai A, Schumacher J, Behrends V, Bundy J, Heydenreich F, Bennett M, et al. GlnK Facilitates the Dynamic Regulation of Bacterial Nitrogen Assimilation. Biophys J. 2017;112:2219-2230 pubmed publisher
    Ammonium assimilation in Escherichia coli is regulated by two paralogous proteins (GlnB and GlnK), which orchestrate interactions with regulators of gene expression, transport proteins, and metabolic pathways...
  10. Durand A, Merrick M. In vitro analysis of the Escherichia coli AmtB-GlnK complex reveals a stoichiometric interaction and sensitivity to ATP and 2-oxoglutarate. J Biol Chem. 2006;281:29558-67 pubmed
    In Escherichia coli, the ammonia channel AmtB and the P(II) signal transduction protein GlnK constitute an ammonium sensory system that effectively couples the intracellular nitrogen regulation system to external changes in ammonium ..
  11. Blauwkamp T, Ninfa A. Antagonism of PII signalling by the AmtB protein of Escherichia coli. Mol Microbiol. 2003;48:1017-28 pubmed
    ..In prokaryotes, AmtB homologues are co-transcribed with a PII paralogue, GlnK, in response to nitrogen limitation...
  12. Coutts G, Thomas G, Blakey D, Merrick M. Membrane sequestration of the signal transduction protein GlnK by the ammonium transporter AmtB. EMBO J. 2002;21:536-45 pubmed
    ..In bacteria and archaea, the Amt structural genes (amtB) are invariably linked to glnK, which encodes a member of the P(II) signal transduction protein family, proteins that regulate enzyme activity and ..
  13. MacPherson K, Xu Y, Cheah E, Carr P, van Heeswijk W, Westerhoff H, et al. Crystallization and preliminary X-ray analysis of Escherichia coli GlnK. Acta Crystallogr D Biol Crystallogr. 1998;54:996-8 pubmed
    The trimeric signal-transduction protein GlnK, from Escherichia coli, has been over-expressed, purified to homogeneity and crystallized. The crystals belong to space group P213 with a = 85.53 A and have two subunits in the asymmetric unit...
  14. Burillo S, Luque I, Fuentes I, Contreras A. Interactions between the nitrogen signal transduction protein PII and N-acetyl glutamate kinase in organisms that perform oxygenic photosynthesis. J Bacteriol. 2004;186:3346-54 pubmed
  15. Javelle A, Severi E, Thornton J, Merrick M. Ammonium sensing in Escherichia coli. Role of the ammonium transporter AmtB and AmtB-GlnK complex formation. J Biol Chem. 2004;279:8530-8 pubmed
    ..In bacteria and archaea the Amt structural genes (amtB) are invariably linked to glnK, which encodes a member of the P(II) signal transduction protein family, proteins that regulate many facets of ..
  16. Blauwkamp T, Ninfa A. Physiological role of the GlnK signal transduction protein of Escherichia coli: survival of nitrogen starvation. Mol Microbiol. 2002;46:203-14 pubmed
    Escherichia coli contains two PII-like signal trans-duction proteins, PII and GlnK, involved in nitrogen assimilation...
  17. Ishikita H. Modulation of the protein environment in the hydrophilic pore of the ammonia transporter protein AmtB upon GlnK protein binding. FEBS Lett. 2007;581:4293-7 pubmed
    ..NH3/NH4(+)) through the channel protein AmtB is inhibited by the binding of the signal transduction protein GlnK. In the AmtB-GlnK binding interface, there exists an NH3/NH4(+) binding site--Am6...
  18. Ma H, Boogerd F, Goryanin I. Modelling nitrogen assimilation of Escherichia coli at low ammonium concentration. J Biotechnol. 2009;144:175-83 pubmed publisher
    ..on a previously published model, the new model included AmtB mediated ammonium transport and AmtB regulation by GlnK. Protein concentrations and several parameter values were determined or refined based on new experimental data...
  19. Thomas G, Coutts G, Merrick M. The glnKamtB operon. A conserved gene pair in prokaryotes. Trends Genet. 2000;16:11-4 pubmed
  20. Salinas P, Contreras A. Identification and analysis of Escherichia coli proteins that interact with the histidine kinase NtrB in a yeast two-hybrid system. Mol Genet Genomics. 2003;269:574-81 pubmed
    ..Three different genes, encoding GlnB, GlnK and AspA, respectively, were found among 64 positive clones identified from E...
  21. Ninfa A, Atkinson M. PII signal transduction proteins. Trends Microbiol. 2000;8:172-9 pubmed
  22. Xu Y, Cheah E, Carr P, van Heeswijk W, Westerhoff H, Vasudevan S, et al. GlnK, a PII-homologue: structure reveals ATP binding site and indicates how the T-loops may be involved in molecular recognition. J Mol Biol. 1998;282:149-65 pubmed publisher
    b>GlnK is a recently discovered homologue of the PII signal protein, an indicator of the nitrogen status of bacteria...