ID   1.11.1.29
DE   mycoredoxin-dependent peroxiredoxin.
CA   [mycoredoxin]-L-dithiol + a hydroperoxide = [mycoredoxin]-L-disulfide +
CA   an alcohol + H2O.
CC   -!- Peroxiredoxins (Prxs) are a ubiquitous family of antioxidant
CC       proteins.
CC   -!- They can be divided into three classes: typical 2-Cys, atypical 2-Cys
CC       and 1-Cys peroxiredoxins.
CC   -!- The peroxidase reaction comprises two steps centered around a redox-
CC       active cysteine called the peroxidatic cysteine.
CC   -!- All three peroxiredoxin classes have the first step in common,
CC       in which the peroxidatic cysteine attacks the peroxide substrate and
CC       is oxidized to S-hydroxycysteine (a sulfenic acid).
CC   -!- The second step of the peroxidase reaction, the regeneration of
CC       cysteine from S-hydroxycysteine, distinguishes the three
CC       peroxiredoxin classes.
CC   -!- For typical 2-Cys Prxs, in the second step, the peroxidatic
CC       S-hydroxycysteine from one subunit is attacked by the 'resolving'
CC       cysteine located in the C-terminus of the second subunit, to form an
CC       intersubunit disulfide bond, which is then reduced by one of several
CC       cell-specific thiol-containing reductants completing the catalytic
CC       cycle.
CC   -!- In the atypical 2-Cys Prxs, both the peroxidatic cysteine and its
CC       resolving cysteine are in the same polypeptide, so their reaction
CC       forms an intrachain disulfide bond.
CC   -!- The 1-Cys Prxs conserve only the peroxidatic cysteine, so its
CC       regeneration involves direct interaction with a reductant molecule.
CC   -!- Mycoredoxin-dependent enzymes are found in Mycobacteria.
CC   -!- Following the reduction of the substrate, the sulfenic acid
CC       derivative of the peroxidatic cysteine forms a protein mixed
CC       disulfide with the N-terminal cysteine of mycoredoxin, which is then
CC       reduced by the C-terminal cysteine of mycoredoxin, restoring the
CC       peroxiredoxin to active state and resulting in an intra-protein
CC       disulfide in mycoredoxin.
CC   -!- The disulfide is eventually reduced by mycothiol.
CC   -!- Formerly EC 1.11.1.15.
DR   P65689, AHPE_MYCBO ;  P9WIE2, AHPE_MYCTO ;  P9WIE3, AHPE_MYCTU ;
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