Spectroscopic and Computational Studies of Ni3+Complexes with Mixed S/N Ligation:  Implications for the Active Site of Nickel Superoxide Dismutase

2007 ◽  
Vol 46 (21) ◽  
pp. 8511-8523 ◽  
Author(s):  
Adam T. Fiedler ◽  
Thomas C. Brunold
Keyword(s):  
Superoxide Dismutase ◽  
Active Site ◽  
Computational Studies ◽  
Nickel Superoxide Dismutase

Synthesis and Characterization of NiIIIN3S2 Complexes as Active Site Models for the Oxidized Form of Nickel Superoxide Dismutase

2014 ◽  
Vol 20 (21) ◽  
pp. 6283-6286 ◽  
Author(s):  
Chien-Wei Chiang ◽  
Yun-Li Chu ◽  
Hong-Ling Chen ◽  
Ting-Shen Kuo ◽  
Way-Zen Lee
Keyword(s):  
Superoxide Dismutase ◽  
Active Site ◽  
Synthesis And Characterization ◽  
Nickel Superoxide Dismutase

A shared mechanistic pathway for pyridoxal phosphate–dependent arginine oxidases

2021 ◽  
Vol 118 (40) ◽  
pp. e2012591118
Author(s):  
Elesha R. Hoffarth ◽  
Kersti Caddell Haatveit ◽  
Eugene Kuatsjah ◽  
Gregory A. MacNeil ◽  
Simran Saroya ◽  
...  
Keyword(s):  
Active Site ◽  
Evolutionary History ◽  
Pyridoxal Phosphate ◽  
Computational Studies ◽  
Single Electron Transfer ◽  
Oxidation Reactions ◽  
Unified Framework ◽  
Precise Positioning ◽  
X Ray ◽  
Mechanistic Pathway

The mechanism by which molecular oxygen is activated by the organic cofactor pyridoxal phosphate (PLP) for oxidation reactions remains poorly understood. Recent work has identified arginine oxidases that catalyze desaturation or hydroxylation reactions. Here, we investigate a desaturase from the Pseudoalteromonas luteoviolacea indolmycin pathway. Our work, combining X-ray crystallographic, biochemical, spectroscopic, and computational studies, supports a shared mechanism with arginine hydroxylases, involving two rounds of single-electron transfer to oxygen and superoxide rebound at the 4′ carbon of the PLP cofactor. The precise positioning of a water molecule in the active site is proposed to control the final reaction outcome. This proposed mechanism provides a unified framework to understand how oxygen can be activated by PLP-dependent enzymes for oxidation of arginine and elucidates a shared mechanistic pathway and intertwined evolutionary history for arginine desaturases and hydroxylases.

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