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The ABC exporter MsbA probed by solid state NMR – challenges and opportunities

  • Hundeep Kaur , Andrea Lakatos , Roberta Spadaccini , Ramona Vogel , Christian Hoffmann , Johanna Becker-Baldus , Olivier Ouari , Paul Tordo , Hassane Mchaourab and Clemens Glaubitz EMAIL logo
Published/Copyright: April 3, 2015
Biological Chemistry
From the journal Biological Chemistry Volume 396 Issue 9-10

Abstract

ATP binding cassette (ABC) transporters form a superfamily of integral membrane proteins involved in translocation of substrates across the membrane driven by ATP hydrolysis. Despite available crystal structures and extensive biochemical data, many open questions regarding their transport mechanisms remain. Therefore, there is a need to explore spectroscopic techniques such as solid state NMR in order to bridge the gap between structural and mechanistic data. In this study, we investigate the feasibility of using Escherichia coli MsbA as a model ABC transporter for solid state NMR studies. We show that optimised solubilisation and reconstitution procedures enable preparing stable and homogenous protein samples. Depending on the duration of solubilisation, MsbA can be obtained in either an apo- or in a native lipid A bound form. Building onto these optimisations, the first promising MAS-NMR spectra with narrow lines have been recorded. However, further sensitivity improvements are required so that complex NMR experiments can be recorded within a reasonable amount of time. We therefore demonstrate the usability of paramagnetic doping for rapid data acquisition and explore dynamic nuclear polarisation as a method for general signal enhancement. Our results demonstrate that solid state NMR provides an opportunity to address important biological questions related to complex mechanisms of ABC transporters.

Keywords: ATP binding cassette (ABC) transporter; dynamic nuclear polarisation (DNP); lipid A; MAS-NMR; MsbA; paramagnetic relaxation enhancement (PRE)
Corresponding author: Clemens Glaubitz, Institute for Biophysical Chemistry and Centre for Biomolecular Magnetic Resonance, Goethe University Frankfurt, Max-von-Laue-Str. 9, D-60438 Frankfurt/Main, Germany, e-mail:

Acknowledgments

The work was supported by a DFG research grant through SFB 807 ‘Transport and communication across membranes’ and by a DFG equipment grant (GL 307/4–1) to C.G. H.M. acknowledges support by NIH grant U54-GM087519. MALDI-MS data were kindly provided by Dr. Ute Bahr (Institute for Pharmaceutical Chemistry, Goethe University Frankfurt).

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Received: 2015-2-4
Accepted: 2015-3-26
Published Online: 2015-4-3
Published in Print: 2015-9-1

©2015 by De Gruyter

Articles in the same Issue

  1. Frontmatter
  2. Meeting Report
  3. Membrane Transport and Communication in Frankfurt: Speakers’ Summary – Highlights
  4. HIGHLIGHT: MEMBRANE TRANSPORT AND COMMUNICATION
  5. Structure, function, evolution, and application of bacterial Pnu-type vitamin transporters
  6. Team work at its best – TAPL and its two domains
  7. The volume-regulated anion channel is formed by LRRC8 heteromers – molecular identification and roles in membrane transport and physiology
  8. Extending native mass spectrometry approaches to integral membrane proteins
  9. Functional diversity of the superfamily of K+ transporters to meet various requirements
  10. The structure of Na+-translocating of NADH:ubiquinone oxidoreductase of Vibrio cholerae: implications on coupling between electron transfer and Na+ transport
  11. Hybrid rotors in F1Fo ATP synthases: subunit composition, distribution, and physiological significance
  12. Homeostatic control of biological membranes by dedicated lipid and membrane packing sensors
  13. The transporter associated with antigen processing: a key player in adaptive immunity
  14. The pseudo-atomic structure of an RND-type tripartite multidrug efflux pump
  15. The assembly and disassembly of the AcrAB-TolC three-component multidrug efflux pump
  16. A universal mechanism for transport and regulation of CPA sodium proton exchangers
  17. Biosynthesis of membrane dependent proteins in insect cell lysates: identification of limiting parameters for folding and processing
  18. Fluorescence and excited state dynamics of the deprotonated Schiff base retinal in proteorhodopsin
  19. Regulatory role of charged clusters in the N-terminal domain of BetP from Corynebacterium glutamicum
  20. The contribution of methionine to the stability of the Escherichia coli MetNIQ ABC transporter-substrate binding protein complex
  21. The ABC exporter MsbA probed by solid state NMR – challenges and opportunities
  22. Functional properties of LptA and LptD in Anabaena sp. PCC 7120
https://doi.org/10.1515/hsz-2015-0119
Keywords for this article
ATP binding cassette (ABC) transporter; dynamic nuclear polarisation (DNP); lipid A; MAS-NMR; MsbA; paramagnetic relaxation enhancement (PRE)

Articles in the same Issue

  1. Frontmatter
  2. Meeting Report
  3. Membrane Transport and Communication in Frankfurt: Speakers’ Summary – Highlights
  4. HIGHLIGHT: MEMBRANE TRANSPORT AND COMMUNICATION
  5. Structure, function, evolution, and application of bacterial Pnu-type vitamin transporters
  6. Team work at its best – TAPL and its two domains
  7. The volume-regulated anion channel is formed by LRRC8 heteromers – molecular identification and roles in membrane transport and physiology
  8. Extending native mass spectrometry approaches to integral membrane proteins
  9. Functional diversity of the superfamily of K+ transporters to meet various requirements
  10. The structure of Na+-translocating of NADH:ubiquinone oxidoreductase of Vibrio cholerae: implications on coupling between electron transfer and Na+ transport
  11. Hybrid rotors in F1Fo ATP synthases: subunit composition, distribution, and physiological significance
  12. Homeostatic control of biological membranes by dedicated lipid and membrane packing sensors
  13. The transporter associated with antigen processing: a key player in adaptive immunity
  14. The pseudo-atomic structure of an RND-type tripartite multidrug efflux pump
  15. The assembly and disassembly of the AcrAB-TolC three-component multidrug efflux pump
  16. A universal mechanism for transport and regulation of CPA sodium proton exchangers
  17. Biosynthesis of membrane dependent proteins in insect cell lysates: identification of limiting parameters for folding and processing
  18. Fluorescence and excited state dynamics of the deprotonated Schiff base retinal in proteorhodopsin
  19. Regulatory role of charged clusters in the N-terminal domain of BetP from Corynebacterium glutamicum
  20. The contribution of methionine to the stability of the Escherichia coli MetNIQ ABC transporter-substrate binding protein complex
  21. The ABC exporter MsbA probed by solid state NMR – challenges and opportunities
  22. Functional properties of LptA and LptD in Anabaena sp. PCC 7120
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