ISIS Neutron and Muon Source Data Journal

This is a page describing data taken during an experiment at the ISIS Neutron and Muon Source. Information about the ISIS Neutron and Muon Source can be found at https://www.isis.stfc.ac.uk.


Probing phospholipid transport by the Pqi pathway

Abstract: In Gram-negative bacteria, the cell envelope is a complex tripartite structure composed of an inner membrane (IM), outer membrane (OM), and an intervening peptidoglycan layer. These components collectively maintain cell integrity and shape. While the envelope?s structure is well characterized, replicating it in vitro remains challenging. Current models typically isolate either the OM or IM, limiting study of processes spanning the entire envelope. This is particularly problematic for studying trans-envelope transport systems?multi-protein machineries essential for processes such as OM biogenesis. These systems often include components embedded in both membranes and may physically tether the IM and OM. One example is the PqiABC complex, implicated in phospholipid transport, which spans the periplasm and links the membranes. We have developed a method to reconstitute PqiABC on a planar surface, enabling structural analysis. Using differentially deuterated inner and outer membranes, we observed lipid mixing between bilayers. However, whether this mixing is mediated by PqiABC or is an artefact of membrane deposition remains unclear. This proposal will address this via a deuterated lipid pulse-chase experiment. By comparing lipid transport in wild-type PqiABC and a non-functional mutant, we will determine whether phospholipid transfer is protein-mediated or incidental?clarifying PqiABC?s role and supporting future study of trans-envelope systems.

Principal Investigator: Professor Tim Knowles
Experimenter: Miss Hannah Johnston
Experimenter: Miss Charlotte Wilson
Experimenter: Dr Stephen Hall
Local Contact: Dr Luke Clifton
Experimenter: Mr Abdulaziz Alzahrani

DOI: 10.5286/ISIS.E.RB2520401

ISIS Experiment Number: RB2520401

Part DOI Instrument Public release date Download Link
10.5286/ISIS.E.RB2520401-1 OFFSPEC 18 March 2029 Download

Publisher: STFC ISIS Neutron and Muon Source

Data format: RAW/Nexus
Select the data format above to find out more about it.

Data Citation

The recommended format for citing this dataset in a research publication is as:
[author], [date], [title], [publisher], [doi]

For Example:
Professor Tim Knowles et al; (2026): Probing phospholipid transport by the Pqi pathway, STFC ISIS Neutron and Muon Source, https://doi.org/10.5286/ISIS.E.RB2520401

Data is released under the CC-BY-4.0 license.



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