Proton pathways in green fluorescence protein.
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ABSTRACT:
SUBMITTER: Agmon N
PROVIDER: S-EPMC1305344 | biostudies-literature | 2005 Apr
REPOSITORIES: biostudies-literature
Publications
Proton pathways in green fluorescent protein (GFP) are more extended than previously reported. In the x-ray data of wild-type GFP, a two-step exit pathway exists from the active site to the protein surface, controlled by a threonine switch. A proton entry pathway begins at a glutamate-lysine cluster around Glu-5, and extends all the way to the buried Glu-222 near the active site. This structural evidence suggests that GFP may function as a portable light-driven proton-pump, with proton emitted i ...[more]
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