Update based on the original article by Donald M. Kurtz, Jr, Encyclopedia of Inorganic Chemistry © 2005 John Wiley & Sons, Ltd
Iron: Non-Heme Proteins with Diiron-Carboxylate Active Sites
Published Online: 23 SEP 2013
Copyright © 2011 John Wiley & Sons, Ltd. All rights reserved.
Encyclopedia of Inorganic and Bioinorganic Chemistry
How to Cite
Kurtz, D. M., Boice, E., Caranto, J. D., Frederick, R. E., Masitas, C. A. and Miner, K. D. 2013. Iron: Non-Heme Proteins with Diiron-Carboxylate Active Sites. Encyclopedia of Inorganic and Bioinorganic Chemistry. 1–18.
- Published Online: 23 SEP 2013
Non-heme diiron-carboxylate (NHDC) active sites are found in several classes of monooxygenases, oxidases, and dioxygen transport or sensing proteins, as well as a few metallohydrolases. The unique and defining structural feature of NHDC sites consists of two non-heme irons bridged by at least one carboxylate-containing amino acid residue. A second characteristic feature is a bridging solvent ligand, either oxo or hydroxo in at least the diferric state. NHDC sites also feature terminal ligands derived from histidine and carboxylate residues. The hemerythrin superfamily functions have expanded from reversible dioxygen binding to include sensing of iron, dioxygen, or redox status. Substantial progress has been made in characterization of flavo-diiron enzymes, including its nitric oxide reductase mechanism. A diiron urease is a recent addition to the metallohydrolase family. The variety of characterized NHDC O2-activating enzymes has increased substantially since the previous compilation in this encyclopedia. Novel monooxygenation mechanisms have been identified.
- carboxylate bridge;
- oxo bridge;
- histidine ligand;