Skip to main content
Article thumbnail
Location of Repository

Structure, Binding, and Activity of Syd, a SecY-interacting Protein*S⃞

By Kush Dalal, Nham Nguyen, Meriem Alami, Jennifer Tan, Trevor F. Moraes, Woo Cheol Lee, Robert Maurus, Stephen S. Sligar, Gary D. Brayer and Franck Duong

Abstract

The Syd protein has been implicated in the Sec-dependent transport of polypeptides across the bacterial inner membrane. Using Nanodiscs, we here provide direct evidence that Syd binds the SecY complex, and we demonstrate that interaction involves the two electropositive and cytosolic loops of the SecY subunit. We solve the crystal structure of Syd and together with cysteine cross-link analysis, we show that a conserved concave and electronegative groove constitutes the SecY-binding site. At the membrane, Syd decreases the activity of the translocon containing loosely associated SecY-SecE subunits, whereas in detergent solution Syd disrupts the SecYEG heterotrimeric associations. These results support the role of Syd in proofreading the SecY complex biogenesis and point to the electrostatic nature of the Sec channel interaction with its cytosolic partners

Topics: Membrane Transport, Structure, Function, and Biogenesis
Publisher: American Society for Biochemistry and Molecular Biology
OAI identifier: oai:pubmedcentral.nih.gov:2658082
Provided by: PubMed Central
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • http://www.pubmedcentral.nih.g... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.