[Export of metabolites by the proteins of the DMT and RhtB families and its possible role in intercellular communication].
The earlier published and new experimental data are summarized on the properties of the genes encoding the membrane proteins of the DMT family (RhtA (YbiF), EamA (YdeD), YijE, YddG, YedA, PecM, eukaryotic nucleoside phosphate sugar and hexose phosphate transporters), the RhtB/LysE family (RhtB, RhtC, LeuE, YahN, EamB (YfiK), ArgO (YggA), CmaU), as well as some other families (YicM, YdhC, YdeAB, YdhE (NorE)). These proteins are involved in the export of amino acids, purines, and other metabolites from the cell. The expression of most of the genes encoding these proteins is not induced by the substrates they transport but is controlled by the global regulation systems, such as the Lrp protein, and activated by the signal compounds involved in the intracellular communication. The level of expression, assessed in experiments on translational fusion of the corresponding bacterial genes with the beta-galactosidase gene, depends on the growth phase of the bacterial culture, composition of the medium, and some stress factors, such as pH osmolarity or decreased aeration. The efflux of normal cell metabolites is assumed to be the natural function of these proteins. This function may play a role in density-dependent behavior of cell populations (quorum sensing). It may have been enhanced in the course of evolution via specialization of these proteins in the efflux of compounds derived from metabolic intermediates and adjusted to the role of transmitters.
Zakataeva
N P
NP
Kutukova
E A
EA
Gronskiĭ
S V
SV
Troshin
P V
PV
Livshits
V A
VA
Aleshin
V V
VV
D000596:Amino Acids / Q000378:metabolism; D001419:Bacteria / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D018407:Bacterial Physiological Phenomena; D001426:Bacterial Proteins / Q000235:genetics / Q000502:physiology*; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology*; D003470:Culture Media; D029968:Escherichia coli Proteins / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial; D006863:Hydrogen-Ion Concentration; D051756:Leucine-Responsive Regulatory Protein / Q000235:genetics / Q000502:physiology; D008565:Membrane Proteins / Q000502:physiology*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000502:physiology; D009994:Osmolar Concentration; D010100:Oxygen / Q000378:metabolism; D011687:Purines / Q000378:metabolism; D015398:Signal Transduction; D001616:beta-Galactosidase / Q000235:genetics
D000596:Amino Acids; D001426:Bacterial Proteins; D002352:Carrier Proteins; D003470:Culture Media; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D011687:Purines; C475818:RhtA protein, E coli; C000603332:YijE protein, E coli; D051756:Leucine-Responsive Regulatory Protein; D001616:beta-Galactosidase; D010100:Oxygen