EPJ E Highlight - Remote control of transport through nanopores

Dynamics of dextran sulfate transport through aerolysin nanopore.

New study outlines key factors affecting the transfer of molecules through biological channels

In our bodies, the transfer of genetic information, viral infections and protein trafficking, as well as the synthesis and the degradation of biomolecules, are all phenomena that require the transport of molecules through channels. Improving our control of these channels and the capacity of molecules to get across could have many potential applications in the fields of energy, biotechnology and medicine. These include ultra-fast DNA sequencing, detection of biological markers used in disease diagnostics, protein folding, high-resolution determination of the size of biological molecules or even the control of ion or biomolecule transport through the protein sensor. In a new study published in EPJ E, Manuela Pastoriza-Gallego from the University Paris-Seine, France, and colleagues have shown how to alter external factors, such as external voltage, to control the transport of a dextran sulfate molecule - a polyelectrolyte - through the nanopores of the aerolysin protein channel.

Molecules crossing such biological channels are often made up of a chain of atoms, which may be larger than the pore diameter, typically smaller than 2 nanometers in width and 10 nanometers in length. This means a driving force is necessary to overcome the energy barrier of the channel confining the chain to the nanopore. The level of this energy barrier also depends also on the molecule-pore interactions. The authors previously studied a different nanopore, called alpha-hemolysin.

To study the dynamics in confined medium at the single molecule level, scientists rely on electrical detection. They have identified the impact of partially folded protein chains when crossing the channel, which lead to very long blockades in nanopores. Based on a comparison with their previous work on alpha-hemolysin nanopores, they have proven that protein unfolding transition is independent of the nanopore used. For completely unfolded protein, the authors have demonstrated that the entry into the pore needs to overcome a minimum energy barrier. They have also shown that the transport time decreases exponentially with the applied voltage and increases with the protein chain length.

Dynamics of polyelectrolyte through aerolysin channel as a function of applied voltage and concentration. M. Pastoriza-Gallego, B.Thiébot, L. Bacri, L. Auvray, J. Pelta (2018), Eur. Phys. J. E 41: 58, DOI 10.1140/epje/i2018-11661-4

This was our first experience of publishing with EPJ Web of Conferences. We contacted the publisher in the middle of September, just one month prior to the Conference, but everything went through smoothly. We have had published MNPS Proceedings with different publishers in the past, and would like to tell that the EPJ Web of Conferences team was probably the best, very quick, helpful and interactive. Typically, we were getting responses from EPJ Web of Conferences team within less than an hour and have had help at every production stage.
We are very thankful to Solange Guenot, Web of Conferences Publishing Editor, and Isabelle Houlbert, Web of Conferences Production Editor, for their support. These ladies are top-level professionals, who made a great contribution to the success of this issue. We are fully satisfied with the publication of the Conference Proceedings and are looking forward to further cooperation. The publication was very fast, easy and of high quality. My colleagues and I strongly recommend EPJ Web of Conferences to anyone, who is interested in quick high-quality publication of conference proceedings.

On behalf of the Organizing and Program Committees and Editorial Team of MNPS-2019, Dr. Alexey B. Nadykto, Moscow State Technological University “STANKIN”, Moscow, Russia. EPJ Web of Conferences vol. 224 (2019)

ISSN: 2100-014X (Electronic Edition)

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