General diffusion porins are passive transmembrane channels. We have explored the possibility to create artificial nanopores starting from natural beta-barrel structures. Structural elements of bacterial porins were used to build a series of artificial nanopores. The basic module was selected by multi-alignment of general diffusion porins. The sequence corresponded to a highly conserved motif containing two beta-strands, which was obtained from Escherichia coli OmpF. Dimeric to octameric repeats were obtained through cDNA recombinant technology. The hexameric repeat was used to test its properties. This protein was expressed, purified and reconstituted in the planar bilayer membranes. It was able to form channels in membranes with a conductance of 300 pS in 150 mM KCl and did not show any relevant voltage-dependence.
Generation of artificial channels by multimerization of beta-strands from natural porin
Lolicato Marco;
2011-01-01
Abstract
General diffusion porins are passive transmembrane channels. We have explored the possibility to create artificial nanopores starting from natural beta-barrel structures. Structural elements of bacterial porins were used to build a series of artificial nanopores. The basic module was selected by multi-alignment of general diffusion porins. The sequence corresponded to a highly conserved motif containing two beta-strands, which was obtained from Escherichia coli OmpF. Dimeric to octameric repeats were obtained through cDNA recombinant technology. The hexameric repeat was used to test its properties. This protein was expressed, purified and reconstituted in the planar bilayer membranes. It was able to form channels in membranes with a conductance of 300 pS in 150 mM KCl and did not show any relevant voltage-dependence.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
