ISIS Neutron and Muon Source Data Journal

Pumping lipids across the gram-negative envelope

Abstract: The PqiABC complex has been implicated in phospholipid (PL) transport between the inner and outer membrane of gram-negative bacteria. This one complex spans the periplasm with components in both membranes, tethering them together. In a recent experiment, RB2220703, we proposed utilising this trans-envelope complex as a scaffold to create a planar double membrane architecture, providing a unique gram-negative envelope mimetic to probe envelope biology. Our Preliminary Neutron Reflectometry (NR) experiments confirmed its successful creation. Furthermore, we predicted PqiABC to be a proton motive force (PMF) driven PL pump based on structural homology. By altering the buffer pH, we were able to emulate the PMF leading to a time dependent drop in the Scattering Length Density of the bilayer attached to the solid support. Suggestive of influx of hydrogenous material into the membrane, consistent with PMF driven PL transport. We have known for 40 years that PLs are transported to the outer membrane via a PMF mediated process. However, to date, no process has been identified. Our results provide tentative clues that PqiABC may be responsible. We already have complimentary QCMD, FTIR and cell based assays. NR is the last critical experiment required to complete this story. Rapid access will allow us to complete this research in a timely manner, whilst the importance of the field, means that this work is likely to have significant impact

Experimenter: Miss Hannah Johnston
Experimenter: Dr Tim Knowles
Experimenter: Miss Rachel Holyfield
Experimenter: Mr William Chatterton
Local Contact: Dr Luke Clifton

DOI: 10.5286/ISIS.E.RB2300004

ISIS Experiment Number: RB2300004

Publisher: STFC ISIS Neutron and Muon Source

Data format: RAW/Nexus
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Data Citation

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

For Example:
Miss Hannah Johnston et al; (2023): Pumping lipids across the gram-negative envelope, STFC ISIS Neutron and Muon Source, https://doi.org/10.5286/ISIS.E.RB2300004

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