BAmSA: Visualising transmembrane regions in protein complexes using biotinylated amphipols and electron microscopy
Thomas Noe Perry1, Hager Souabni2, Chiara Rapisarda1
1CNRS/Université de Bordeaux UMR 5234, European Institute of Chemistry and Biology, 2 rue Robert Escarpit, 33607 Pessac, France; G5 Biologie Structurale de la Sécrétion Bactérienne, UMR 3528, CNRS, Institut Pasteur, 25-28 rue du Docteur Roux, 75015 Paris, France.
Biochimica Et Biophysica Acta. Biomembranes
|November 17, 2018
Summary
We developed BAmSA, a new method to locate transmembrane regions in membrane protein complexes. This technique aids in understanding complex organization using electron microscopy without genetic or chemical modifications.
Area of Science:
- Structural biology
- Biochemistry
- Microscopy
Background:
- Membrane proteins (MPs) are crucial in cellular functions.
- Characterizing MP complexes is challenging due to purification and crystallization difficulties.
- Electron microscopy (EM) has advanced MP structural determination.
Purpose of the Study:
- To present BAmSA, a novel method for localizing transmembrane (TM) regions in MP complexes.
- To provide a general procedure for tagging TM regions without genetic or chemical modification.
- To offer a new strategy for exploring MP complex organization.
Main Methods:
- BAmSA method for localizing transmembrane regions.
- Labeling of TM regions without genetic or chemical modification.
- Direct visualization of labels on EM images and reconstructions.
Main Results:
- BAmSA enables direct visualization of labeled TM regions.
- The method is applicable to raw negative-stain EM images, class averages, and 3D reconstructions.
- Facilitates the study of challenging MP complexes like bacterial secretion systems.
Conclusions:
- BAmSA offers a novel strategy for investigating MP complex organization.
- The method overcomes limitations in structural characterization of MPs.
- Provides valuable insights into the arrangement of transmembrane regions within protein complexes.
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