Activation of the Class Ib Ribonucleotide Reductase
by a Flavodoxin Reductase in <i>Bacillus cereus</i>
Marie Lofstad
Ingvild Gudim
Marta Hammerstad
Åsmund
Kjendseth Røhr
Hans-Petter Hersleth
10.1021/acs.biochem.6b00699.s001
https://acs.figshare.com/articles/journal_contribution/Activation_of_the_Class_Ib_Ribonucleotide_Reductase_by_a_Flavodoxin_Reductase_in_i_Bacillus_cereus_i_/3793542
To reduce ribonucleotides to deoxyribonucleotides,
the manganese-bound
form of class Ib ribonucleotide reductase (RNR) must be activated
via a pathway that involves redox protein(s). The reduced flavoprotein
NrdI is an important protein in this pathway, as it reduces dioxygen
to superoxide. Superoxide then reacts with the RNR Mn<sup>II</sup><sub>2</sub> site to generate a tyrosyl radical that is required
for catalysis. A native NrdI reductase has not yet been identified.
We herein demonstrate through kinetic and spectroscopic studies that
an endogenous flavodoxin reductase can function as the NrdI reductase
in <i>Bacillus cereus</i>. When the flavodoxin reductase
reduces NrdI, tyrosyl radical formation in RNR is promoted under aerobic
conditions, significantly increasing the radical yield. Thus, a missing
piece of the class Ib RNR NrdI redox pathway has finally been identified.
2016-08-25 00:00:00
flavodoxin reductase
tyrosyl
protein
NrdI reductase
Bacillus cereus
class Ib RNR NrdI redox pathway
RNR Mn II 2 site
class Ib ribonucleotide reductase
Class Ib Ribonucleotide Reductase