Chromophore formation in DsRed occurs by a branched pathway.
Like GFP, the fluorescent protein DsRed has a chromophore that forms autocatalytically within the folded protein, but the mechanism of DsRed chromophore formation has been unclear. It was proposed that an initial oxidation generates a green chromophore, and that a final oxidation yields the red chromophore. However, this model does not adequately explain why a mature DsRed sample contains a mixture of green and red chromophores. We present evidence that the maturation pathway for DsRed branches upstream of chromophore formation. After an initial oxidation step, a final oxidation to form the acylimine of the red chromophore is in kinetic competition with a dehydration to form the green chromophore. This scheme explains why green and red chromophores are alternative end points of the maturation pathway.
Strack
Rita L
RL
Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois 60637, USA.
Strongin
Daniel E
DE
Mets
Laurens
L
Glick
Benjamin S
BS
Keenan
Robert J
RJ
D003116:Color; D006861:Hydrogen Peroxide / Q000737:chemistry; D007700:Kinetics; D008164:Luminescent Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008956:Models, Chemical; D009154:Mutation; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D012995:Solubility
D008164:Luminescent Proteins; C413663:fluorescent protein 583; D006861:Hydrogen Peroxide; D010100:Oxygen