Size-dependent forced PEG partitioning into channels: VDAC, OmpC, and α-hemolysin

Journal Article · 26 July 2016 · Proceedings of the National Academy of Sciences of the United States of America

DOI: https://doi.org/10.1073/pnas.1602716113 · OSTI ID:1274822

Aksoyoglu, M. Alphan ^[1]; Podgornik, Rudolf ^[2]; Bezrukov, Sergey M. ^[3]; Gurnev, Philip A. ^[4]; Muthukumar, Murugappan ^[5]; Parsegian, V. Adrian ^[1]

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1. Department of Physics, University of Massachusetts, Amherst, MA 01003,
2. Department of Physics, University of Massachusetts, Amherst, MA 01003,, Department of Physics, Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana, Slovenia,, Department of Theoretical Physics, J. Stefan Institute, 1000 Ljubljana, Slovenia,
3. Section on Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892,
4. Department of Physics, University of Massachusetts, Amherst, MA 01003,, Section on Molecular Transport, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892,
5. Department of Polymer Science and Engineering, University of Massachusetts, Amherst, MA 01003

Significance With consequences for the selective partitioning of large molecules in cells, polymer partitioning into nanopores is instructive for single-molecule sensing as well as for polymer-assisted transport and packaging. Here we detect and analyze not only passive but also forced size-dependent partitioning of binary mixtures of differently sized PEGs. We probe three structurally different channels exhibiting forced partitioning that can be understood conceptually as well as quantitatively within a “polymers-pushing-polymers” model, allowing good estimates for the size-dependent pore penetration energy differences. Beyond proof of concept, forced partitioning in cells can now be recognized and used as a new tool for molecule-selective transport and active osmotically regulated packaging.

• Research Organization: Univ. of Massachusetts, Amherst, MA (United States)
• Sponsoring Organization: USDOE; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division
• Grant/Contract Number: SC0008176
• OSTI ID: 1274822
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Journal Issue: 32 Vol. 113; ISSN 0027-8424
• Publisher: Proceedings of the National Academy of SciencesCopyright Statement
• Country of Publication: United States
• Language: English