Protein folding triggered by electron transfer.

T Pascher; J P Chesick; J R Winkler; H B Gray

doi:10.1126/science.271.5255.1558

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Protein folding triggered by electron transfer.

T Pascher·J P Chesick·J R Winkler·H B Gray

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Abstract

Rapid photochemical electron injection into unfolded ferricytochrome c titrated with 2.3 to 4.6 M guanidine hydrochloride (GuHCL) at pH 7 and 40 degrees C produced unfolded ferrocytochrome, which then converted to the folded protein. Two folding phases were observed: a fast process with a time constant of 40 microseconds (4.6 M GuHCL), and a slower phase with a rate constant of 90 +/- 20 per second (2.3 M GuHCL). The activation free energy for the slow step varied linearly with GuHCL concentration; the rate constant, extrapolated to aqueous solution, was 7600 per second. Electron-transfer methods can bridge the nanosecond to millisecond measurement time gap for protein folding.

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Cytochrome c Group Electrons Guanidine Guanidines Oxidation-Reduction Photochemistry Protein Denaturation Protein Folding Temperature Thermodynamics Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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T Pascher, J P Chesick, J R Winkler, H B Gray. 1996-03-15. Protein folding triggered by electron transfer.. https://doi.org/10.1126/science.271.5255.1558

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