5ITC

2.2-Angstrom in meso crystal structure of Haloquadratum Walsbyi Bacteriorhodopsin (HwBR) from Styrene Maleic Acid (SMA) Polymer Nanodiscs

Summary for 5ITC

• Entry DOI: 10.2210/pdb5itc/pdb
• Related: 5ITE
• Descriptor: Bacteriorhodopsin-I, RETINAL, (2R)-2,3-dihydroxypropyl (9Z)-octadec-9-enoate, ... (5 entities in total)
• Functional Keywords: bacteriorhodopsin from haloquadratum walsbyi, lipidic cubic phase, styrene maleic acid (sma) polymer nanodisc, detergent-free, membrane protein
• Biological source: Haloquadratum walsbyi
• Cellular location: Cell membrane ; Multi-pass membrane protein : Q18DH8
• Total number of polymer chains: 3
• Total formula weight: 92375.59

Authors

Broecker, J.,Eger, B.T.,Ernst, O.P. (deposition date: 2016-03-16, release date: 2017-01-25, Last modification date: 2024-11-06)

Primary citation

Broecker, J.,Eger, B.T.,Ernst, O.P.
Crystallogenesis of Membrane Proteins Mediated by Polymer-Bounded Lipid Nanodiscs.
Structure, 25:384-392, 2017

PubMed Abstract: For some membrane proteins, detergent-mediated solubilization compromises protein stability and functionality, often impairing biophysical and structural analyses. Hence, membrane-protein structure determination is a continuing bottleneck in the field of protein crystallography. Here, as an alternative to approaches mediated by conventional detergents, we report the crystallogenesis of a recombinantly produced membrane protein that never left a lipid bilayer environment. We used styrene-maleic acid (SMA) copolymers to solubilize lipid-embedded proteins into SMA nanodiscs, purified these discs by affinity and size-exclusion chromatography, and transferred proteins into the lipidic cubic phase (LCP) for in meso crystallization. The 2.0-Å structure of an α-helical seven-transmembrane microbial rhodopsin thus obtained is of high quality and virtually identical to the 2.2-Å structure obtained from traditional detergent-based purification and subsequent LCP crystallization.

PubMed: 28089451
DOI: 10.1016/j.str.2016.12.004

Experimental method

X-RAY DIFFRACTION (1.999 Å)