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Catch me if you can! Oxidative protein trapping in the intermembrane space of mitochondria

Johannes M Herrmann1, Roman Köhl

  • 1Department of Cell Biology, University of Kaiserslautern, 67663 Kaiserslautern, Germany. hannes.herrmann@biologie.uni-kl.de

The Journal of Cell Biology
|February 22, 2007
PubMed

Insights

Mitochondrial intermembrane space machinery oxidatively folds proteins, trapping them within mitochondria. This process, conserved from bacteria, drives protein translocation from the cytosol.

Area of Science:

  • Cell Biology
  • Mitochondrial Biology
  • Protein Folding

Background:

  • The mitochondrial intermembrane space (IMS) is a compartment with bacterial origins.
  • It contains essential machinery for protein oxidative folding.

Purpose of the Study:

  • To investigate the role of the IMS in protein folding and translocation.
  • To understand the evolutionary conservation of oxidative protein folding.

Main Methods:

  • Analysis of protein import and folding mechanisms in mitochondria.
  • Comparative studies of IMS machinery and bacterial periplasmic systems.

Main Results:

  • Mitochondrial IMS machinery catalyzes oxidative folding of imported proteins.
  • Disulfide bond formation in the IMS locks proteins in a folded state.
  • Folded proteins are trapped in mitochondria due to their inability to cross the outer membrane.

Conclusions:

  • The IMS oxidative folding system is conserved from the bacterial periplasm.
  • This conserved mechanism drives the vectorial translocation of proteins into mitochondria.
  • Protein oxidation in the IMS is crucial for mitochondrial protein import and function.

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