Protein dynamics enhance electronic coupling in electron transfer complexes.
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.
Chohan
K K
KK
Department of Chemistry, University of Leicester, Leicester LE1 7RH, United Kingdom.
Jones
M
M
Grossmann
J G
JG
Frerman
F E
FE
Scrutton
N S
NS
Sutcliffe
M J
MJ
D004579:Electron Transport; D005420:Flavoproteins / Q000737:chemistry*; D006801:Humans; D010084:Oxidation-Reduction; D010089:Oxidoreductases, N-Demethylating / Q000737:chemistry; D010231:Paracoccus denitrificans / Q000737:chemistry; D011485:Protein Binding; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D012542:Scattering, Radiation; D014965:X-Rays
D005420:Flavoproteins; D010089:Oxidoreductases, N-Demethylating; C023186:trimethylamine dehydrogenase