Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Conformational Dynamics of the Lipopolysaccharide from Escherichia coli O91 Revealed by Nuclear Magnetic Resonance Spectroscopy and Molecular Simulations
Stockholm University, Faculty of Science, Department of Organic Chemistry.
Stockholm University, Faculty of Science, Department of Organic Chemistry.
Show others and affiliations
Number of Authors: 52017 (English)In: Biochemistry, ISSN 0006-2960, E-ISSN 1520-4995, Vol. 56, no 29, p. 3826-3839Article in journal (Refereed) Published
Abstract [en]

The outer leaflet of the outer membrane in Gram-negative bacteria contains lipopolysaccharides (LPS) as a major component, and the outer membrane provides a physical barrier and protection against hostile environments. The enterohemorrhagic Escherichia coli of serogroup O91 has an O-antigen polysaccharide (PS) with five sugar residues in the repeating unit (RU), and the herein studied O-antigen PS contains similar to 10 RUs. H-1-C-13 HSQC-NOESY experiments on a 1-C-13-labeled PS were employed to deduce H-1-H-1 cross-relaxation rates and transglycosidic (3)J(CH) related to the psi torsional angles were obtained by H-1-H-1 NOESY experiments. Dynamical parameters were calculated from the molecular dynamics (MD) simulations of the PS in solution and compared to those from C-13 nuclear magnetic resonance (NMR) relaxation studies. Importantly, the MD simulations can reproduce the dynamical behavior of internal correlation times along the PS chain. Two-dimensional free energy surfaces of glycosidic torsion angles delineate the conformational space available to the O-antigen. Although similar with respect to populated states in solution, the O-antigen in LPS bilayers has more extended chains as a result of spatial limitations due to close packing. Calcium ions are highly abundant in the phosphate-containing core region mediating LPS LPS association that is crucial for maintaining bilayer integrity, and the negatively charged O-antigen promotes a high concentration of counterbalancing potassium ions. The ensemble of structures present for the PS in solution is captured by the NMR experiments, and the similarities between the O-antigen on its own and as a constituent of the full LPS in a bilayer environment make it possible to realistically describe the LPS conformation and dynamics from the MD simulations.

Place, publisher, year, edition, pages
2017. Vol. 56, no 29, p. 3826-3839
National Category
Biological Sciences Chemical Sciences
Identifiers
URN: urn:nbn:se:su:diva-147164DOI: 10.1021/acs.biochem.7b00106ISI: 000406573100016PubMedID: 28609625OAI: oai:DiVA.org:su-147164DiVA, id: diva2:1143741
Available from: 2017-09-22 Created: 2017-09-22 Last updated: 2017-09-22Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textPubMed

Search in DiVA

By author/editor
Widmalm, Göran
By organisation
Department of Organic Chemistry
In the same journal
Biochemistry
Biological SciencesChemical Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 30 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf