Format

Send to

Choose Destination
Biochim Biophys Acta Biomembr. 2018 Nov;1860(11):2436-2445. doi: 10.1016/j.bbamem.2018.07.003. Epub 2018 Jul 18.

How to minimize dye-induced perturbations while studying biomembrane structure and dynamics: PEG linkers as a rational alternative.

Author information

1
Department of Physics, University of Helsinki, P. O. Box 64, FI-00014 Helsinki, Finland; Laboratory of Physics, Tampere University of Technology, P. O. Box 692, FI-33101 Tampere, Finland.
2
Department of Physics, University of Helsinki, P. O. Box 64, FI-00014 Helsinki, Finland; Laboratory of Physics, Tampere University of Technology, P. O. Box 692, FI-33101 Tampere, Finland; Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
3
Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstr. 108, 01307 Dresden, Germany.
4
MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, United Kingdom.
5
Department of Physics, University of Helsinki, P. O. Box 64, FI-00014 Helsinki, Finland.
6
MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, United Kingdom; Institute of Applied Optics Friedrich-Schiller-University Jena, Max-Wien Platz 4, 07743 Jena, Germany; Leibniz Institute of Photonic Technology e.V., Albert-Einstein-Straße 9, 07745 Jena, Germany.
7
Department of Physics, University of Helsinki, P. O. Box 64, FI-00014 Helsinki, Finland; Laboratory of Physics, Tampere University of Technology, P. O. Box 692, FI-33101 Tampere, Finland; MEMPHYS - Center for Biomembrane Physics (www.memphys.dk). Electronic address: Ilpo.Vattulainen@helsinki.fi.

Abstract

Organic dye-tagged lipid analogs are essential for many fluorescence-based investigations of complex membrane structures, especially when using advanced microscopy approaches. However, lipid analogs may interfere with membrane structure and dynamics, and it is not obvious that the properties of lipid analogs would match those of non-labeled host lipids. In this work, we bridged atomistic simulations with super-resolution imaging experiments and biomimetic membranes to assess the performance of commonly used sphingomyelin-based lipid analogs. The objective was to compare, on equal footing, the relative strengths and weaknesses of acyl chain labeling, headgroup labeling, and labeling based on poly-ethyl-glycol (PEG) linkers in determining biomembrane properties. We observed that the most appropriate strategy to minimize dye-induced membrane perturbations and to allow consideration of Brownian-like diffusion in liquid-ordered membrane environments is to decouple the dye from a membrane by a PEG linker attached to a lipid headgroup. Yet, while the use of PEG linkers may sound a rational and even an obvious approach to explore membrane dynamics, the results also suggest that the dyes exploiting PEG linkers interfere with molecular interactions and their dynamics. Overall, the results highlight the great care needed when using fluorescent lipid analogs, in particular accurate controls.

KEYWORDS:

Atomistic simulation; Fluorescent probe; Lipid membrane; Molecular dynamics simulation; PEG linker; Super-resolution microscopy

PMID:
30028957
DOI:
10.1016/j.bbamem.2018.07.003
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center