A kinetic model for molecular diffusion through pores

Copyright © 2016 Elsevier B.V. All rights reserved..

The number of pathogens developing multiple drug resistance is ever increasing. The impact on healthcare systems is huge and the need for novel antibiotics as well a new way to develop them is urgent, especially against Gram-negative bacteria. The first defense of these bacteria is the outer membrane, where unspecific protein channels (porins) modulate nutrients passive diffusion. Also polar antibiotics enter through this path and down-regulation and/or mutation of porins are very common in drug resistant strains. Our inability to come up with novel effective antibiotics mostly relies upon the insufficient comprehension of the key molecular features enabling better penetration through porins. Molecular dynamics simulations offer an extraordinary tool in the study of the dynamics of biological systems; however, one of the major drawbacks of this method is that its use is currently restricted to study time scales of the order of microsecond. Enhanced sampling methods like Metadynamics have been recently used to investigate the diffusion of antibiotics through bacterial porins. The main limitation is that dynamical properties cannot be estimated because of the different potential that the systems under study are experiencing. Recently, the scope of Metadynamics has been extended. By applying an a posteriori analysis one can obtain rates of transitions and rate-limiting steps of the process under study, directly comparable with kinetic data extracted from electrophysiology experiments. In this work, we apply this method to the study of the permeability of Escherichia coli's OmpF with respect to Meropenem, finding good agreement with the residence time obtained analyzing experimental current noise. This article is part of a Special Issue entitled: Membrane Proteins edited by J.C. Gumbart and Sergei Noskov.

Medienart:

E-Artikel

Erscheinungsjahr:

2016

Erschienen:

2016

Enthalten in:

Zur Gesamtaufnahme - volume:1858

Enthalten in:

Biochimica et biophysica acta - 1858(2016), 7 Pt B vom: 17. Juli, Seite 1772-7

Sprache:

Englisch

Beteiligte Personen:

D'Agostino, Tommaso [VerfasserIn]
Salis, Samuele [VerfasserIn]
Ceccarelli, Matteo [VerfasserIn]

Links:

Volltext

Themen:

Anti-Bacterial Agents
Bacterial Outer Membrane Proteins
Ion Channels
Journal Article
Kinetics
Lipid Bilayers
Molecular dynamics
Porins
Research Support, Non-U.S. Gov't
Transport

Anmerkungen:

Date Completed 13.09.2016

Date Revised 26.11.2016

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.bbamem.2016.01.004

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM256715211