Protein dynamics enhance electronic coupling in electron transfer complexes.

K K Chohan; M Jones; J G Grossmann; F E Frerman; N S Scrutton; M J Sutcliffe

doi:10.1074/jbc.m101341200

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Protein dynamics enhance electronic coupling in electron transfer complexes.

K K Chohan·M Jones·J G Grossmann·F E Frerman·N S Scrutton·M J Sutcliffe

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Abstract

Electron-transferring flavoproteins (ETFs) from human and Paracoccus denitrificans have been analyzed by small angle x-ray scattering, showing that neither molecule exists in a rigid conformation in solution. Both ETFs sample a range of conformations corresponding to a large rotation of domain II with respect to domains I and III. A model of the human ETF.medium chain acyl-CoA dehydrogenase complex, consistent with x-ray scattering data, indicates that optimal electron transfer requires domain II of ETF to rotate by approximately 30 to 50 degrees toward domain I relative to its position in the x-ray structure. Domain motion establishes a new "robust engineering principle" for electron transfer complexes, tolerating multiple configurations of the complex while retaining efficient electron transfer.

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Electron Transport Flavoproteins Humans Oxidation-Reduction Oxidoreductases, N-Demethylating Paracoccus denitrificans Protein Binding Protein Conformation Protein Structure, Tertiary Scattering, Radiation X-Rays Journal Article Research Support, Non-U.S. Gov't

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K K Chohan, M Jones, J G Grossmann, F E Frerman, N S Scrutton, M J Sutcliffe. 2001-06-27. Protein dynamics enhance electronic coupling in electron transfer complexes.. https://doi.org/10.1074/jbc.m101341200

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