A molecular switch and electronic circuit modulate catalase activity in catalase-peroxidases.
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ABSTRACT:
SUBMITTER: Carpena X
PROVIDER: S-EPMC1369206 | biostudies-other | 2005 Dec
REPOSITORIES: biostudies-other
Publications
A molecular switch and electronic circuit modulate catalase activity in catalase-peroxidases.
Carpena Xavier X Wiseman Ben B Deemagarn Taweewat T Singh Rahul R Switala Jacek J Ivancich Anabella A Fita Ignacio I Loewen Peter C PC
EMBO reports 20051201 12
The catalase reaction of catalase-peroxidases involves catalase-specific features built into a peroxidase core. An arginine, 20 A from the active-site heme, acts as a molecular switch moving between two conformations, one that activates heme oxidation and one that activates oxoferryl heme reduction by H(2)O(2), facilitating the catalatic pathway in a peroxidase. The influence of the arginine is imparted to the heme through its association with or dissociation from a tyrosinate that modulates rea ...[more]
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