Mass spectrometry profiles superoxide-induced intramolecular disulfide in the FMN-binding subunit of mitochondrial Complex I.

ABSTRACT: Protein thiols with regulatory functions play a critical role in maintaining the homeostasis of the redox state in mitochondria. One major host of regulatory cysteines in mitochondria is Complex I, with the thiols primarily located on its 51 kDa FMN-binding subunit. In response to oxidative stress, these thiols are expected to form intramolecular disulfide bridges as one of their oxidative post-translational modifications. Here, to test this hypothesis and gain insights into the molecular pattern of disulfide in Complex I, the isolated bovine Complex I was prepared. Superoxide (O(2)(.-)) is generated by Complex I under the conditions of enzyme turnover. O(2)(.-)-induced intramolecular disulfide formation at the 51, kDa subunit was determined by tandem mass spectrometry and database searchi

SUBMITTER: Zhang L 

PROVIDER: S-EPMC2614441 | biostudies-literature | 2008 Dec

REPOSITORIES: biostudies-literature