The Escherichia coli AmtB protein as a model system for understanding ammonium transport by Amt and Rh proteins.
The Escherichia coli ammonium transport protein (AmtB) has become the model system of choice for analysis of the process of ammonium uptake by the ubiquitous Amt family of inner membrane proteins. Over the past 6 years we have developed a range of genetic and biochemical tools in this system. These have allowed structure/function analysis to develop rapidly, offering insight initially into the membrane topology of the protein and most recently leading to the solution of high-resolution 3D structures. Genetic analysis has revealed a novel regulatory mechanism that is apparently conserved in prokaryotic Amt proteins and genetic approaches are also now being used to dissect structure/function relationships in Amt proteins. The now well-recognised homology between the Amt proteins, found in archaea, eubacteria, fungi and plants, and the Rhesus proteins, found characteristically in animals, also means that studies on E. coli AmtB can potentially shed light on structure/function relationships in the clinically important Rh proteins.
Merrick
M
M
Department of Molecular Microbiology, John Innes Centre, Colney Lane, Norwich, NR4 7UH Norwich, UK. mike.merrick@bbsrc.ac.uk
Javelle
A
A
Durand
A
A
Severi
E
E
Thornton
J
J
Avent
N D
ND
Conroy
M J
MJ
Bullough
P A
PA
D000641:Ammonia / Q000378:metabolism; D001692:Biological Transport; D001798:Blood Proteins / Q000737:chemistry / Q000502:physiology; D027682:Cation Transport Proteins / Q000737:chemistry / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000502:physiology*; D005786:Gene Expression Regulation; D006801:Humans; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000502:physiology; D008958:Models, Molecular; D009713:Nucleotidyltransferases / Q000502:physiology; D051922:PII Nitrogen Regulatory Proteins / Q000502:physiology; D011487:Protein Conformation; D000644:Quaternary Ammonium Compounds / Q000378:metabolism*; D012204:Rh-Hr Blood-Group System / Q000737:chemistry / Q000502:physiology; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000502:physiology*; D015398:Signal Transduction; D013045:Species Specificity; D013329:Structure-Activity Relationship; D013379:Substrate Specificity
C111096:AmtB protein, E coli; D001798:Blood Proteins; D027682:Cation Transport Proteins; D029968:Escherichia coli Proteins; C088951:MEP1 protein, S cerevisiae; C107270:MEP2 protein, S cerevisiae; C107271:MEP3 protein, S cerevisiae; D008562:Membrane Glycoproteins; D051922:PII Nitrogen Regulatory Proteins; D000644:Quaternary Ammonium Compounds; C498523:RHAG protein, human; C066468:RHCE protein, human; D012204:Rh-Hr Blood-Group System; D029701:Saccharomyces cerevisiae Proteins; D000641:Ammonia; C497878:glnK protein, E coli; D009713:Nucleotidyltransferases