| Literature DB >> 19942137 |
Hidekazu Tsutsui1, Hideaki Shimizu, Hideaki Mizuno, Nobuyuki Nukina, Toshiaki Furuta, Atsushi Miyawaki.
Abstract
KikGR is a fluorescent protein engineered to display green-to-red photoconvertibility that is induced by irradiation with ultraviolet or violet light. Similar to Kaede and EosFP, two naturally occurring photoconvertible proteins, KikGR contains a His(62)-Tyr(63)-Gly(64) tripeptide sequence, which forms a green chromophore that can be photoconverted to a red one via formal beta-elimination and subsequent extension of a pi-conjugated system. Using a crystallizable variant of KikGR, we determined the structures of both the green and red state at 1.55 A resolution. The double bond between His(62)-C(alpha) and His(62)-C(beta) in the red chromophore is in a cis configuration, indicating that rotation along the His(62) C(alpha)-C(beta) bond occurs following cleavage of the His(62) N(alpha)-C(alpha) bond. This structural rearrangement provides evidence that the beta-elimination reaction governing the green-to-red photoconversion of KikGR follows an E1 (elimination, unimolecular) mechanism.Entities:
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Year: 2009 PMID： 19942137 DOI： 10.1016/j.chembiol.2009.10.010
Source DB: PubMed Journal: Chem Biol ISSN： 1074-5521