Structural highlights
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Monomeric Kusabira Orange (mKO) is a green fluorescent protein (GFP)-like protein that emits orange light at a peak of 559 nm. We analyzed its X-ray structure at 1.65 A and found a novel three-ring chromophore that developed autocatalytically from a Cys65-Tyr66-Glu67 tripeptide in which the side chain of Cys65 formed the third 2-hydroxy-3-thiazoline ring. As a result, the chromophore contained the CNCOH group at the 2-position of the imidazolinone moiety such that the conjugated pi-electron system of the chromophore was more extended than that of GFP but less extended than that of the Discosoma sp. red fluorescent protein (DsRed). Since a sulfur atom has potent nucleophilic character, the third 3-thiazoline ring is rapidly and completely cyclized. Furthermore, our structure reveals the presence of a pi-pi stacking interaction between His197 and the chromophore as well as a pi-cation interaction between Arg69 and the chromophore. These structural findings are sufficient to account for the orange emission, pH tolerance, and photostability of mKO.
Structural Characterization of a Thiazoline-Containing Chromophore in an Orange Fluorescent Protein, Monomeric Kusabira Orange.,Kikuchi A, Fukumura E, Karasawa S, Mizuno H, Miyawaki A, Shiro Y Biochemistry. 2008 Oct 10. PMID:18844376[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Kikuchi A, Fukumura E, Karasawa S, Mizuno H, Miyawaki A, Shiro Y. Structural Characterization of a Thiazoline-Containing Chromophore in an Orange Fluorescent Protein, Monomeric Kusabira Orange. Biochemistry. 2008 Oct 10. PMID:18844376 doi:10.1021/bi800727v
