TY - JOUR
T1 - EPR study of 1Asp-3Cys ligated 4Fe-4S iron-sulfur cluster in NB-protein (BchN-BchB) of a dark-operative protochlorophyllide reductase complex
AU - Kondo, Toru
AU - Nomata, Jiro
AU - Fujita, Yuichi
AU - Itoh, Shigeru
N1 - Funding Information:
We thank Tadashi Mizoguchi and Hitoshi Tamiaki for their kind donation of Chl c and Hiroyuki Mino for helpful discussions for the EPR measurement. This work was supported by Grants-in-Aid from the Japanese Society for the Promotion of Science (JSPS) for Scientific Research (B) (No. 19370064 ) to S.I. and (No. 20200063) to Y.F ., Precursory Research for Embryonic Science and Technology of the Japan Science and Technology Agency (JST) to Y.F., and a JSPS research fellowship for young scientists (No. 21008983 ) to T.K. S. I. thanks Dr. Masahiro Ishiura in Center for Gene Research in Nagoya University for kind discussion and providing facilities.
PY - 2011/1/3
Y1 - 2011/1/3
N2 - Dark-operative protochlorophyllide oxidoreductase, a nitrogenase-like enzyme, contains two [4Fe-4S] clusters, one in the L-protein ((BchL) 2) and the other in the NB-protein ((BchN-BchB)2). The reduced NB-cluster in the NB-protein, which is ligated by 1Asp/3Cys residues, showed a broad S = 3/2 electron paramagnetic resonance signal that is rather rare in [4Fe-4S] clusters. A 4Cys-ligated NB-cluster in the mutated variant BchB-D36C protein, in which the Asp36 was replaced by a Cys, gave a rhombic normal S = 1/2 signal and lost the catalytic activity. The results suggest that Asp36 contributes to the low redox potential necessary to reduce protochlorophyllide.
AB - Dark-operative protochlorophyllide oxidoreductase, a nitrogenase-like enzyme, contains two [4Fe-4S] clusters, one in the L-protein ((BchL) 2) and the other in the NB-protein ((BchN-BchB)2). The reduced NB-cluster in the NB-protein, which is ligated by 1Asp/3Cys residues, showed a broad S = 3/2 electron paramagnetic resonance signal that is rather rare in [4Fe-4S] clusters. A 4Cys-ligated NB-cluster in the mutated variant BchB-D36C protein, in which the Asp36 was replaced by a Cys, gave a rhombic normal S = 1/2 signal and lost the catalytic activity. The results suggest that Asp36 contributes to the low redox potential necessary to reduce protochlorophyllide.
KW - Bacteriochlorophyll biosynthesis
KW - BchB
KW - BchN
KW - Electron paramagnetic resonance
KW - Iron-sulfur cluster
KW - Protochlorophyllide
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U2 - 10.1016/j.febslet.2010.11.044
DO - 10.1016/j.febslet.2010.11.044
M3 - Article
C2 - 21126521
AN - SCOPUS:78650912337
SN - 0014-5793
VL - 585
SP - 214
EP - 218
JO - FEBS Letters
JF - FEBS Letters
IS - 1
ER -