RRC ID 35255
Author Radchenko MV, Thornton J, Merrick M.
Title Control of AmtB-GlnK complex formation by intracellular levels of ATP, ADP, and 2-oxoglutarate.
Journal J Biol Chem
Abstract P(II) proteins are one of the most widespread families of signal transduction proteins in nature, being ubiquitous throughout bacteria, archaea, and plants. They play a major role in coordinating nitrogen metabolism by interacting with, and regulating the activities of, a variety of enzymes, transcription factors, and membrane transport proteins. The regulatory properties of P(II) proteins derive from their ability to bind three effectors: ATP, ADP, and 2-oxoglutarate. However, a clear model to integrate physiological changes with the consequential structural changes that mediate P(II) interaction with a target protein has so far not been developed. In this study, we analyzed the fluctuations in intracellular effector pools in Escherichia coli during association and dissociation of the P(II) protein GlnK with the ammonia channel AmtB. We determined that key features promoting AmtB-GlnK complex formation are the rapid drop in the 2-oxoglutarate pool upon ammonium influx and a simultaneous, but transient, change in the ATP/ADP ratio. We were also able to replicate AmtB-GlnK interactions in vitro using the same effector combinations that we observed in vivo. This comprehensive data set allows us to propose a model that explains the way in which interactions between GlnK and its effectors influence the conformation of GlnK and thereby regulate its interaction with AmtB.
Volume 285(40)
Pages 31037-45
Published 2010-10-1
DOI 10.1074/jbc.M110.153908
PII S0021-9258(19)88991-3
PMID 20639578
PMC PMC2945594
MeSH Adenosine Diphosphate / metabolism* Adenosine Triphosphate / metabolism* Cation Transport Proteins / metabolism* Escherichia coli / metabolism* Escherichia coli Proteins / metabolism* Ion Transport / physiology Ketoglutaric Acids / metabolism* Models, Biological* Multiprotein Complexes / metabolism* Nucleotidyltransferases / metabolism* PII Nitrogen Regulatory Proteins / metabolism* Quaternary Ammonium Compounds / metabolism
IF 4.238
Times Cited 56
Prokaryotes E. coli JW3841