4fpd: Difference between revisions
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== Function == | == Function == | ||
[https://www.uniprot.org/uniprot/BACR_HALSA BACR_HALSA] Light-driven proton pump. | [https://www.uniprot.org/uniprot/BACR_HALSA BACR_HALSA] Light-driven proton pump. | ||
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== Publication Abstract from PubMed == | |||
Despite extensive investigation, the precise mechanism controlling the opening of the cytoplasmic proton uptake pathway in bacteriorhodopsin (bR) has remained a mystery. From an analysis of the X-ray structure of the D96G/F171C/F219L triple mutant of bR and 60 independent molecular dynamics simulations of bR photointermediates, we report that the deprotonation of D96, a key residue in proton transfer reactions, serves two roles that occur sequentially. First, D96 donates a proton to the Schiff base. Subsequently, the deprotonation of D96 serves to "unlatch" the cytoplasmic side. The latching function of D96 appears to be remarkably robust, functioning to open hydration channels in all photointermediate structures. These results suggest that the protonation state of D96 may be the critical biophysical cue controlling the opening and closing of the cytoplasmic half-channel in bR. We suspect that this protonation-switch mechanism could also be utilized in other proton pumps to minimize backflow and reinforce directionality. | |||
Deprotonation of d96 in bacteriorhodopsin opens the proton uptake pathway.,Wang T, Sessions AO, Lunde CS, Rouhani S, Glaeser RM, Duan Y, Facciotti MT Structure. 2013 Feb 5;21(2):290-7. doi: 10.1016/j.str.2012.12.018. PMID:23394942<ref>PMID:23394942</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
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<div class="pdbe-citations 4fpd" style="background-color:#fffaf0;"></div> | |||
==See Also== | ==See Also== | ||
*[[Bacteriorhodopsin 3D structures|Bacteriorhodopsin 3D structures]] | *[[Bacteriorhodopsin 3D structures|Bacteriorhodopsin 3D structures]] | ||
== References == | |||
<references/> | |||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
Latest revision as of 09:31, 17 October 2024
Deprotonation of D96 in bacteriorhodopsin opens the proton uptake pathwayDeprotonation of D96 in bacteriorhodopsin opens the proton uptake pathway
Structural highlights
FunctionBACR_HALSA Light-driven proton pump. Publication Abstract from PubMedDespite extensive investigation, the precise mechanism controlling the opening of the cytoplasmic proton uptake pathway in bacteriorhodopsin (bR) has remained a mystery. From an analysis of the X-ray structure of the D96G/F171C/F219L triple mutant of bR and 60 independent molecular dynamics simulations of bR photointermediates, we report that the deprotonation of D96, a key residue in proton transfer reactions, serves two roles that occur sequentially. First, D96 donates a proton to the Schiff base. Subsequently, the deprotonation of D96 serves to "unlatch" the cytoplasmic side. The latching function of D96 appears to be remarkably robust, functioning to open hydration channels in all photointermediate structures. These results suggest that the protonation state of D96 may be the critical biophysical cue controlling the opening and closing of the cytoplasmic half-channel in bR. We suspect that this protonation-switch mechanism could also be utilized in other proton pumps to minimize backflow and reinforce directionality. Deprotonation of d96 in bacteriorhodopsin opens the proton uptake pathway.,Wang T, Sessions AO, Lunde CS, Rouhani S, Glaeser RM, Duan Y, Facciotti MT Structure. 2013 Feb 5;21(2):290-7. doi: 10.1016/j.str.2012.12.018. PMID:23394942[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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