Ionophore

An ionophore is a molecule which ions are transported through a membrane.

Some bacteria produce ionophores, ie molecules that increase the permeability of membranes for ions. Often, such molecules have an antibiotic effect, as it should reduce ion concentration gradient. Some ionophores are used by bacteria, as a pore -forming toxin. A distinction Carrier ionophores and channel-forming ionophores:

  • Carrier ionophores bind ions diffuse through the cell membrane and put the ions on the other side again.
  • Channel-forming ionophores are small proteins (peptides ), which form pores or transmembrane channels, through which, the respective ions diffuse (ion channels).
  • Chromoionophores wear chromophoric groups and include Crown ethers, which result in complexation with metal ions in a color change.

Examples

  • 2,4-dinitrophenol (H carriers, protonophore )
  • Calixarenes ( Pb2 ), s.a. Examples chromoionophores
  • Fusafungine ( alkali - cation transport )
  • Gramicidin A ( K channel ) (H , Na )
  • Ionomycin (Ca2 - Carrier)
  • Crown ethers (Na , K )
  • Nystatin (K channel )
  • Porphyrin ( NO2 )
  • Salinomycin (K )
  • Valinomycin (K carrier )

Examples chromoionophores

  • Calixarenes (Cs, Rb ), for example a bis ( arylazo ) calixarene - crown ether derivative
  • Diaza -18- kron - 6 ether chromoionophores (Ca)

Examples of other ionophores

  • Calcimycin ( A23187 ) (Ca2 )
  • Beauvericin (Ca2 , Ba2 )
  • Enniatin ( ammonium )
  • FCCP ( Carbonylcyanide -p- trifluoromethoxyphenylhydrazon ) (H carriers, protonophore ) and CCCP ( carbonyl cyanide m- chlorophenylhydrazon ) (H carriers, protonophore )
  • Lasalocid
  • Macro Cycle ( NO3- )
  • Monensin (Na / H exchanger)
  • Nigericin (K , H , Pb2 )
  • Nonactin ( ammonium ionophore I)
  • Perfluorooctanesulfonamide (H )
Tetrahedron (journal) Digital Object Identifier Tetrahedron Letters
416231
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