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The DOI matches its Crossref record; 64 of the 64 references it cites were found in a registry or an index.

Flexibility in the ABC transporter MsbA: Alternating access with a twist

Open access
Ward, Andrew, Reyes, Christopher L., Yu, Jodie, Roth, Christopher B., Chang, Geoffrey·2007·Proceedings of the National Academy of Sciences

Abstract

ATP-binding cassette (ABC) transporters are integral membrane proteins that translocate a wide variety of substrates across cellular membranes and are conserved from bacteria to humans. Here we compare four x-ray structures of the bacterial ABC lipid flippase, MsbA, trapped in different conformations, two nucleotide-bound structures and two in the absence of nucleotide. Comparison of the nucleotide-free conformations of MsbA reveals a flexible hinge formed by extracellular loops 2 and 3. This hinge allows the nucleotide-binding domains to disassociate while the ATP-binding half sites remain facing each other. The binding of the nucleotide causes a packing rearrangement of the transmembrane helices and changes the accessibility of the transporter from cytoplasmic (inward) facing to extracellular (outward) facing. The inward and outward openings are mediated by two different sets of transmembrane helix interactions. Altogether, the conformational changes between these structures suggest that large ranges of motion may be required for substrate transport.

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Crossref · 10.1073/pnas.0709388104

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Metadata

Authors
Ward, A., Reyes, C. L., Yu, J., Roth, C. B., & Chang, G.
Venue
Proceedings of the National Academy of Sciences
Published
2007-11-27
Volume
104
Issue
48
Pages
19005-19010
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
OpenAlex
W2111935912
Cited by
771
References
64
FWCI
22.34
Type
journal article
Language
en
Open access
green

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CoChat. (2026). Citation check: Flexibility in the ABC transporter MsbA: Alternating access with a twist. https://app.cochat.ai/papers/10.1073/pnas.0709388104
The paper
Ward, A., Reyes, C. L., Yu, J., Roth, C. B., & Chang, G. (2007). Flexibility in the ABC transporter MsbA: Alternating access with a twist. Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.0709388104

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