Properties of the high-spin heme of MauG are altered by binding of preMADH at the protein surface 40 A away.
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ABSTRACT:
SUBMITTER: Feng M
PROVIDER: S-EPMC5905328 | biostudies-literature | 2017 Jun
REPOSITORIES: biostudies-literature
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Properties of the high-spin heme of MauG are altered by binding of preMADH at the protein surface 40 Å away.
Feng Manliang M Ma Zhongxin Z Crudup Breland F BF Davidson Victor L VL
FEBS letters 20170523 11
The diheme enzyme MauG catalyzes oxidative post-translational modifications of a protein substrate, precursor protein of methylamine dehydrogenase (preMADH), that binds to the surface of MauG. The high-spin heme iron of MauG is located 40 Å from preMADH. The ferric heme is an equilibrium of five- and six-coordinate states. PreMADH binding increases the proportion of five-coordinate heme three-fold. On reaction of MauG with H<sub>2</sub> O<sub>2</sub> both hemes become Fe<sup>IV</sup> . In the ab ...[more]
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