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5ite

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2.2-Angstrom in meso crystal structure of Haloquadratum Walsbyi Bacteriorhodopsin (HwBR) from Octylglucoside (OG) Detergent Micelles

Structural highlights

5ite is a 3 chain structure with sequence from Haloquadratum walsbyi DSM 16790. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.182Å
Ligands:	, ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

BACR1_HALWD Light-driven proton pump. The chromophore contains 78% all-trans- and 22% 13-cis-retinal in the dark and 90% all-trans- and 10% 13-cis-retinal upon illumination with >500 nm light.^[1] ^[2] ^[3]

Publication Abstract from PubMed

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-A structure of an alpha-helical seven-transmembrane microbial rhodopsin thus obtained is of high quality and virtually identical to the 2.2-A structure obtained from traditional detergent-based purification and subsequent LCP crystallization.

Crystallogenesis of Membrane Proteins Mediated by Polymer-Bounded Lipid Nanodiscs.,Broecker J, Eger BT, Ernst OP Structure. 2017 Jan 3. pii: S0969-2126(16)30394-X. doi:, 10.1016/j.str.2016.12.004. PMID:28089451^[4]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Sudo Y, Ihara K, Kobayashi S, Suzuki D, Irieda H, Kikukawa T, Kandori H, Homma M. A microbial rhodopsin with a unique retinal composition shows both sensory rhodopsin II and bacteriorhodopsin-like properties. J Biol Chem. 2011 Feb 25;286(8):5967-76. doi: 10.1074/jbc.M110.190058. Epub 2010 , Dec 6. PMID:21135094 doi:http://dx.doi.org/10.1074/jbc.M110.190058
↑ Lobasso S, Lopalco P, Vitale R, Saponetti MS, Capitanio G, Mangini V, Milano F, Trotta M, Corcelli A. The light-activated proton pump Bop I of the archaeon Haloquadratum walsbyi. Photochem Photobiol. 2012 May-Jun;88(3):690-700. doi:, 10.1111/j.1751-1097.2012.01089.x. Epub 2012 Feb 9. PMID:22248212 doi:http://dx.doi.org/10.1111/j.1751-1097.2012.01089.x
↑ Sudo Y, Okazaki A, Ono H, Yagasaki J, Sugo S, Kamiya M, Reissig L, Inoue K, Ihara K, Kandori H, Takagi S, Hayashi S. A blue-shifted light-driven proton pump for neural silencing. J Biol Chem. 2013 Jul 12;288(28):20624-32. doi: 10.1074/jbc.M113.475533. Epub, 2013 May 28. PMID:23720753 doi:http://dx.doi.org/10.1074/jbc.M113.475533
↑ Broecker J, Eger BT, Ernst OP. Crystallogenesis of Membrane Proteins Mediated by Polymer-Bounded Lipid Nanodiscs. Structure. 2017 Jan 3. pii: S0969-2126(16)30394-X. doi:, 10.1016/j.str.2016.12.004. PMID:28089451 doi:http://dx.doi.org/10.1016/j.str.2016.12.004