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Chromophore formation in DsRed occurs by a branched pathway.

ABSTRACT: 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.

SUBMITTER: Strack RL

PROVIDER: S-EPMC2891888 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature

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Chromophore formation in DsRed occurs by a branched pathway.

Strack Rita L RL Strongin Daniel E DE Mets Laurens L Glick Benjamin S BS Keenan Robert J RJ

Journal of the American Chemical Society 20100601 24

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 ...[more]

PMID: 20509651

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