Spontaneous Binding of Molecular Oxygen at the Qo-Site of the bc1 Complex Could Stimulate Superoxide Formation

Peter Husen, Ilia A Solov'yov

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

A key part of the respiratory and photosynthetic pathways is the bc1 protein complex embedded in the inner membrane of mitochondria and the plasma membrane of photosynthetic bacteria. The protein complex pumps protons across the membrane to maintain an electrostatic potential, which is in turn used to drive ATP synthesis. This molecular machinery, however, is suspected to be a source of superoxide, which is toxic to the cell, even in minuscular quantities, and believed to be a factor in aging. Through molecular dynamics simulations, we investigate here the migration of molecular oxygen in the bc1 complex in order to identify possible reaction sites that could lead to superoxide formation. It is found, in particular, that oxygen penetrates spontaneously the Qo binding site of the bc1 complex in the presence of an intermediate semiquinone radical, thus making the Qo-site a strong candidate for being a center of superoxide production.

Original languageEnglish
JournalAmerican Chemical Society. Journal
Volume138
Issue number37
Pages (from-to)12150-12158
ISSN0002-7863
DOIs
Publication statusPublished - 4. Aug 2016

Fingerprint

Dive into the research topics of 'Spontaneous Binding of Molecular Oxygen at the Qo-Site of the bc1 Complex Could Stimulate Superoxide Formation'. Together they form a unique fingerprint.

Cite this