Disulfide Formation in the ER and Mitochondria: Two Solutions to a Common Process
Jan Riemer,1
Neil Bulleid,2
Johannes M. Herrmann1,*
The endoplasmic reticulum (ER) was long considered to be the
only compartment of the eukaryotic cell in which protein folding
is accompanied by enzyme-catalyzed disulfide bond formation.
However, it has recently become evident that cells harbor a
second oxidizing compartment, the mitochondrial intermembrane
space, where disulfide formation facilitates protein translocation
from the cytosol. Moreover, protein oxidation has been implicated
in many mitochondria-associated processes central for human
health such as apoptosis, aging, and regulation of the respiratory
chain. Whereas the machineries of ER and mitochondria both form
disulfides between cysteine residues, they do not share evolutionary
origins and exhibit distinct mechanistic properties. Here, we
summarize the current knowledge of these oxidation systems and
discuss their functional similarities and differences.
2 Faculty of Life Sciences, The Michael Smith Building, University of Manchester, Oxford Road, Manchester M13 9PT, UK.
* To whom correspondence should be addressed. E-mail: hannes.herrmann{at}biologie.uni-kl.de
