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Updated: Jun 4, 2026

Assessment of Submitochondrial Protein Localization in Budding Yeast Saccharomyces cerevisiae
Published on: July 19, 2021
LILBID-mass spectrometry of the mitochondrial preprotein translocase TOM
Frauke Mager1, Lucie Sokolova, Julia Lintzel
1Biophysics Department, Institute of Biology, University of Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart, Germany.
Abstract:
In the present work we applied a novel mass spectrometry method termed laser-induced liquid bead ion desorption mass spectrometry (LILBID-MS) to the outer mitochondrial membrane protein translocon TOM to analyze its subunit composition and stoichiometry. With TOM core complex, purified at high pH, we demonstrate that a TOM core complex of Neurospora crassa is composed of at least two Tom40 and Tom22 molecules, respectively, and more than five small Tom subunits between 5.5 and 6.4 kDa. We show that the multiprotein complex has a total molecular mass higher than 170 depending on the number of Tom5, Tom6 and Tom7 molecules bound.
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