Surface layer protein characterization by small angle x-ray scattering and a fractal mean force concept: From protein structure to nanodisk assemblies

Autor(en)

Christine Horejs, Dietmar Pum, Uwe B. Sleytr, Herwig Peterlik, Alois Jungbauer, Rupert Tscheliessnig

Abstrakt

Surface layers (S-layers) are the most commonly observed cell surface structure of prokaryotic organisms. They are made up of proteins that spontaneously self-assemble into functional crystalline lattices in solution, on various solid surfaces, and interfaces. While classical experimental techniques failed to recover a complete structural model of an unmodified S-layer protein, small angle x-ray scattering (SAXS) provides an opportunity to study the structure of S-layer monomers in solution and of self-assembled two-dimensional sheets. For the protein under investigation we recently suggested an atomistic structural model by the use of molecular dynamics simulations. This structural model is now refined on the basis of SAXS data together with a fractal assembly approach. Here we show that a nondiluted critical system of proteins, which crystallize into monomolecular structures, might be analyzed by SAXS if protein-protein interactions are taken into account by relating a fractal local density distribution to a fractal local mean potential, which has to fulfill the Poisson equation. The present work demonstrates an important step into the elucidation of the structure of S-layers and offers a tool to analyze the structure of self-assembling systems in solution by means of SAXS and computer simulations.

Organisation(en)

Dynamik Kondensierter Systeme

Externe Organisation(en)

Universität für Bodenkultur Wien

Journal

Journal of Chemical Physics

Band

133

Anzahl der Seiten

8

ISSN

0021-9606

DOI

https://doi.org/10.1063/1.3489682

Publikationsdatum

2010

Peer-reviewed

Ja

ÖFOS 2012

1030 Physik, Astronomie

Link zum Portal

https://ucris.univie.ac.at/portal/de/publications/surface-layer-protein-characterization-by-small-angle-xray-scattering-and-a-fractal-mean-force-concept-from-protein-structure-to-nanodisk-assemblies(afc066dc-c3db-4549-9206-e47047f944e3).html