Related Experiment Videos
Ultrafast haem-haem electron transfer in cytochrome c oxidase
M I Verkhovsky1, A Jasaitis, M Wikström
1Helsinki Bioenergetics Group, Institute of Biotechnology and Biocentrum Helsinki, Biocenter 2, Room 2011, P.O. Box 56, University of Helsinki, FI-00014 Helsinki, Finland. marten.wikstrom@helsinki.fi
Abstract:
Electron transfer between the redox centres is essential for the function of the haem-copper oxidases. To date, the fastest rate of electron transfer between the haem groups has been determined to be ca. 3 x 10(5) s(-1). Here, we show by optical spectroscopy that about one half of this electron transfer actually occurs at least three orders of magnitude faster, after photolysis of carbon monoxide from the half-reduced bovine heart enzyme. We ascribe this to the true haem-haem electron tunnelling rate between the haem groups.