TY - JOUR
T1 - Crystal Structures of [NiFe] Hydrogenase Maturation Proteins HypC, HypD, and HypE
T2 - Insights into Cyanation Reaction by Thiol Redox Signaling
AU - Watanabe, Satoshi
AU - Matsumi, Rie
AU - Arai, Takayuki
AU - Atomi, Haruyuki
AU - Imanaka, Tadayuki
AU - Miki, Kunio
PY - 2007/7/6
Y1 - 2007/7/6
N2 - [NiFe] hydrogenase maturation proteins HypC, HypD, and HypE catalyze the insertion and cyanation of the iron center of [NiFe] hydrogenases by an unknown mechanism. We have determined the crystal structures of HypC, HypD, and HypE from Thermococcus kodakaraensis KOD1 at 1.8 Å, 2.07 Å, and 1.55 Å resolution, respectively. The structure of HypD reveals its probable iron binding and active sites for cyanation. An extended conformation of each conserved motif of HypC and HypE allows the essential cysteine residues of both proteins to interact with the active site of HypD. Furthermore, the C-terminal tail of HypE is shown to exist in an ATP-dependent dynamic equilibrium between outward and inward conformations. Unexpectedly, the [4Fe-4S] cluster environment of HypD is quite similar to that of ferredoxin:thioredoxin reductase (FTR), indicating the existence of a redox cascade similar to the FTR system. These results suggest a cyanation reaction mechanism via unique thiol redox signaling in the HypCDE complex.
AB - [NiFe] hydrogenase maturation proteins HypC, HypD, and HypE catalyze the insertion and cyanation of the iron center of [NiFe] hydrogenases by an unknown mechanism. We have determined the crystal structures of HypC, HypD, and HypE from Thermococcus kodakaraensis KOD1 at 1.8 Å, 2.07 Å, and 1.55 Å resolution, respectively. The structure of HypD reveals its probable iron binding and active sites for cyanation. An extended conformation of each conserved motif of HypC and HypE allows the essential cysteine residues of both proteins to interact with the active site of HypD. Furthermore, the C-terminal tail of HypE is shown to exist in an ATP-dependent dynamic equilibrium between outward and inward conformations. Unexpectedly, the [4Fe-4S] cluster environment of HypD is quite similar to that of ferredoxin:thioredoxin reductase (FTR), indicating the existence of a redox cascade similar to the FTR system. These results suggest a cyanation reaction mechanism via unique thiol redox signaling in the HypCDE complex.
KW - SIGNALING
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U2 - 10.1016/j.molcel.2007.05.039
DO - 10.1016/j.molcel.2007.05.039
M3 - Article
C2 - 17612488
AN - SCOPUS:34250874525
VL - 27
SP - 29
EP - 40
JO - Molecular Cell
JF - Molecular Cell
SN - 1097-2765
IS - 1
ER -