Eur. Phys. J. E (2018) 41: 78
https://doi.org/10.1140/epje/i2018-11686-7

Regular Article

Translocation of polyampholytes and intrinsically disordered proteins^⋆

¹ Institut Charles Sadron CNRS-Unistra, 6 rue Boussingault, 67083, Strasbourg Cedex, France
² ESPCI Paris, PSL University, 10 rue Vauquelin, 75005, Paris, France

^* e-mail: albert.johner@ics-cnrs.unistra.fr

Received: 15 April 2018
Accepted: 29 May 2018
Published online: 21 June 2018

Abstract

Polyampholytes are polymers carrying electrical charges of both signs along their backbone. We consider synthetic polyampholytes with a quenched random charge sequence and intrinsically disordered proteins, which have a well-defined charge sequence and behave like polyampholytes in the denaturated state. We study their translocation driven by an electric field through a pore. The role of disorder along the charge sequence of synthetic polyampholytes is analyzed. We show how disorder slows down the translocation dynamics. For intrinsically disordered proteins, the translocation vs. rejection rates by the pore depends on which end is engaged in the translocation channel. We discuss the rejection time, the blockade time distributions and the translocation speed for the charge sequence of two specific intrinsically disordered proteins differing in length and structure.