Reconstitution of the SecY Translocon in Nanodiscs

  • Kush Dalal
  • Franck Duong
Part of the Methods in Molecular Biology book series (MIMB, volume 619)


Secretory proteins are transported across the bacterial envelope using a membrane protein complex called the SecY channel or translocon. Major advances in understanding this transporter have been accomplished with methods including purification, crystallization, and reconstitution of the translocation reaction in vitro. We here describe the incorporation of the SecY complex into supported nanometer scale lipid bilayers called Nanodiscs. These nanoparticles mimic a membrane environment and circumvent many of the technical problems typically observed with liposomes and detergent micelles. The technology is simple, yet should lead to additional new progresses in the field of membrane protein transport.

Key words

Translocon SecY complex detergent lipids nanodiscs nanolipoprotein particles membrane scaffold protein 



The authors thank Dr. Stephen Sligar for providing samples of membrane scaffold protein. KD was supported by the Pacific Century Graduate Scholarship from the BC provincial government. The laboratory is funded by the Canadian Institutes for Health Research (CIHR).


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Kush Dalal
    • 1
  • Franck Duong
    • 1
  1. 1.Department of Biochemistry and Molecular Biology, Life Sciences Institute, Faculty of MedicineUniversity of British ColumbiaVancouverCanada

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