Journal of the American Chemical Society
Page 4 of 9
S.J.E., Department of Chemistry, Boston University, 590
Commonwealth Ave., Boston, MA 02215. Tel 617-358-2816.
FAX 617-353-6466. Email: elliott@bu.edu
becomes yet harder to reduce until products are removed.
This flexibility in terms of potential further demonstrates the
ability of the AdoMet radical cluster to modulate its potential
throughout the catalytic cycle.
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Funding Sources
Here we have directly measured the midpoint potentials of
the auxiliary and AdoMet radical clusters of BtrN using di-
rect electrochemistry. These data shed light on a potential
mechanism (shown in Supporting Information, Scheme S1)
for BtrN and other AdoMet radical dehydrogenases, suggest-
ing a potential role for the auxiliary FeS cluster: when
AdoMet and DOIA are bound, reduction of the active site
cluster in a pH dependent fashion allows for reductive cleav-
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The authors acknowledge the National Institutes of Health
(5R01-GM103268 to S.J.B and S.J.E.) and the National Science
Foundation (MCB-1122977 S.J.E.). No competing financial
interests have been declared.
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ASSOCIATED CONTENT
Pierrel, F.; Hernandez, H.; Johnson, M. K.; Fontecave, M.; Atta,
Supporting Information. Complete description of the materi-
als and methods used, equations used for fitting the pH depend-
encies, the environment of the auxiliary cluster, and a proposed
reaction mechanism. This material is available free of charge via
the Internet at http://pubs.acs.org.”
M. Journal of Biological Chemistry 2003, 278, 29515.
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The Williams & Wilkins Company: Baltimore, 1960.
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