Electrostatic interactions drive the nonsteric directional block of OmpF channel by La3+
Ion channels regulate the transport of molecules and the electric signal transduction in living cells by means of complex and even highly sophisticated mechanisms. We focus here on the crucial role that polyvalent ions, well-known modulators of many biological nanosystems, play in ion channel functi...
Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 29(2013), 49 vom: 10. Dez., Seite 15320-7 |
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Weitere Verfasser: | , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2013
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Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't OmpF protein Porins Lanthanum 6I3K30563S |
Zusammenfassung: | Ion channels regulate the transport of molecules and the electric signal transduction in living cells by means of complex and even highly sophisticated mechanisms. We focus here on the crucial role that polyvalent ions, well-known modulators of many biological nanosystems, play in ion channel function. In particular, we show that trace amounts of lanthanum are able to block the bacterial porin OmpF, a large biological pore of Escherichia coli wide enough to exchange antibiotics and other larger molecules. The underlying mechanism has a strong directional character: it is sensitive to the sign of the applied voltage and to the side of the blocker addition. We explore these channel features by combining planar lipid bilayer electrophysiology at the single channel level, site-directed mutagenesis, and inductively coupled plasma mass spectrometry (ICP-MS). In contrast to other well-described channel blockers, which seem to occlude the narrower part of the pore, we envisage a nonsteric mechanism based on electrostatic interactions |
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Beschreibung: | Date Completed 24.07.2014 Date Revised 10.12.2013 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1520-5827 |
DOI: | 10.1021/la402700m |