Scripps VIVO scripps research logo

  • Index
  • Log in
  • Home
  • People
  • Organizations
  • Research
  • Events
Search form

Nucleotide dependent packing differences in helical crystals of the ABC transporter MsbA

Academic Article
uri icon
  • Overview
  • Research
  • Identity
  • Additional Document Info
  • View All
scroll to property group menus

Overview

related to degree

  • Ward, Andrew, Ph.D. in Biology, Scripps Research 2003 - 2008

authors

  • Ward, Andrew
  • Mulligan, S.
  • Carragher, Bridget
  • Chang, Geoffrey
  • Milligan, Ronald

publication date

  • March 2009

journal

  • Journal of Structural Biology  Journal

abstract

  • Bacterial ATP binding cassette (ABC) exporters fulfill a wide variety of transmembrane transport roles and are homologous to the human multidrug resistance P-glycoprotein. Recent X-ray structures of the exporters MsbA and Sav1866 have begun to describe the conformational changes that accompany the ABC transport cycle. Here we present cryo-electron microscopy structures of MsbA reconstituted into a lipid bilayer. Using ATPase inhibitors, we captured three nucleotide transition states of the transporter that were subsequently reconstituted into helical arrays. The enzyme-substrate complex (trapped by ADP-aluminum fluoride or AMPPNP) crystallized in a different helical lattice than the enzyme-product complex (trapped by ADP-vanadate). Approximately 20A resolution maps were calculated for each state and revealed MsbA to be a dimer with a large channel between the membrane spanning domains, similar to the outward facing crystal structures of MsbA and Sav1866. This suggests that while there are likely structural differences between the nucleotide transition states, membrane embedded MsbA remains in an outward facing conformation while nucleotide is bound.

subject areas

  • ATP-Binding Cassette Transporters
  • Adenine Nucleotides
  • Adenosine Diphosphate
  • Adenosine Triphosphate
  • Adenylyl Imidodiphosphate
  • Bacterial Proteins
  • Cryoelectron Microscopy
  • Crystallization
  • Crystallography
  • Image Processing, Computer-Assisted
  • Liposomes
  • Models, Molecular
  • Protein Conformation
  • Recombinant Proteins
  • Salmonella typhimurium
  • Vanadates
  • Vibrio cholerae
scroll to property group menus

Research

keywords

  • ABC transporter
  • Cryo-electron microscopy
  • Helical crystal
  • MsbA
  • Structure
scroll to property group menus

Identity

PubMed Central ID

  • PMC2703300

International Standard Serial Number (ISSN)

  • 1047-8477

Digital Object Identifier (DOI)

  • 10.1016/j.jsb.2008.11.006

PubMed ID

  • 19114108
scroll to property group menus

Additional Document Info

start page

  • 169

end page

  • 175

volume

  • 165

issue

  • 3

©2021 The Scripps Research Institute | Terms of Use | Powered by VIVO

  • About
  • Contact Us
  • Support