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2-Hydroxy Fatty Acid Enantiomers of Gb3 Impact Shiga Toxin Binding and Membrane Organization.

ABSTRACT: Shiga toxin subunit B (STxB) binding to its cellular receptor Gb3 leads to the formation of protein-lipid clusters and bending of the membrane. A newly developed synthetic route allowed synthesizing the biologically most relevant Gb3-C24:1 2OH species with both, the natural (Gb3-R) as well as the unnatural (Gb3-S) configuration of the 2OH group. The derivatives bind STxB with identical nanomolar affinity, while the propensity to induce membrane tubules in giant unilamellar vesicles is more pronounced for Gb3-S. Fluorescence and atomic force microscopy images of phase-separated supported membranes revealed differences in the lateral organization of the protein on the membrane. Gb3-R favorably induces large and tightly packed protein clusters, while a lower protein density is found on Gb3-S doped membranes.

SUBMITTER: Schutte OM

PROVIDER: S-EPMC4472219 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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2-Hydroxy Fatty Acid Enantiomers of Gb3 Impact Shiga Toxin Binding and Membrane Organization.

Schütte Ole M OM Patalag Lukas J LJ Weber Lucas M C LM Ries Annika A Römer Winfried W Werz Daniel B DB Steinem Claudia C

Biophysical journal 20150601 12

Shiga toxin subunit B (STxB) binding to its cellular receptor Gb3 leads to the formation of protein-lipid clusters and bending of the membrane. A newly developed synthetic route allowed synthesizing the biologically most relevant Gb3-C24:1 2OH species with both, the natural (Gb3-R) as well as the unnatural (Gb3-S) configuration of the 2OH group. The derivatives bind STxB with identical nanomolar affinity, while the propensity to induce membrane tubules in giant unilamellar vesicles is more prono ...[more]

PMID: 26083916

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