Recycling of the high valence States of heme proteins by cysteine residues of THIMET-oligopeptidase.
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ABSTRACT:
SUBMITTER: Ferreira JC
PROVIDER: S-EPMC3815109 | biostudies-literature | 2013
REPOSITORIES: biostudies-literature
Publications
Recycling of the high valence States of heme proteins by cysteine residues of THIMET-oligopeptidase.
Ferreira Juliana C JC Icimoto Marcelo Y MY Marcondes Marcelo F MF Oliveira Vitor V Nascimento Otaciro R OR Nantes Iseli L IL
PloS one 20131101 11
The peptidolytic enzyme THIMET-oligopeptidase (TOP) is able to act as a reducing agent in the peroxidase cycle of myoglobin (Mb) and horseradish peroxidase (HRP). The TOP-promoted recycling of the high valence states of the peroxidases to the respective resting form was accompanied by a significant decrease in the thiol content of the peptidolytic enzyme. EPR (electron paramagnetic resonance) analysis using DBNBS spin trapping revealed that TOP also prevented the formation of tryptophanyl radica ...[more]
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