Acireductone dioxygenase

Exceptionally, in Escherichia coli acireductone dioxygenase (enediol dioxygenase) carries out two enzymatic activities that are responsible for the salvage of methionine, but are encoded by the same gene. Whereas one enzyme is dependent on Fe and produces the ketoacid and formate (Figure 3.34a), the other that is nickel-dependent produces the carboxylic acid, formate, and CO (Figure 3.34b) (Dai et al. 1999). 

ARD Acute respiratory disease acireductone dioxygenase automatic relevance... 

FIGURE 26. Mechanism of acireductone oxidation catalyzed by acireductone dioxygenase, with the atoms from O2 in boldface... 

Ferredoxins. - Kostic and Popchapsky have reviewed the approaches used in their laboratory for stud3ring Cys4Fe2S2 ferredoxins and Ni(II)-contain-ing acireductone dioxygenase. They emphasize the utility of C-detected 2D... 

The only known Ni(ii)-containing dioxygenase ARD (acireducton dioxygenase), which catalyzes the oxidative decomposition of yS-diketones, operates in the analogous way [40], This applies to the functional enzyme models, namely, Cu(ii)- and Fe(ii)-containing quercetin 2,3-dioxygenases, which catalyze the decomposition of yS-diketones in the enol form to carbonyl compounds with CO evolution [41-42],... 

Acireductone dioxygenase (ARD) is a widely spread enzyme, found in bacteria and in eukaryotic organisms, which catalyzes the incorporation of two oxygen... 

Fig. 8. Structural scheme of the active site of Ni-acireductone dioxygenase.

SCHEME 5.1 The reaction of acac-ligand oxygenation in Ni(aoac)2 follows a mechanism analogous to those of Nill-containing Acireductone Dioxygenase (ARD). 

SCHEME 5.3 Acireductone Dioxygenases Ni-ARD and Fe-ARD (a)25 are involved in the methionine recycle pathway (b). 

Chai, S.C. Ju, T Dang, M Goldsmith, R.B. Maroney, M.J. Pochapsky,Th.C. Characterization of Metal Binding in the Active Sites of Acireductone Dioxygenase Isoforms from Klebsiella ATCC 8724. Biochemistry 2008, 47, 2428-2435. 

Allpress, C.J. GrubeL K. Szajna-FuUer, E. Arif, A.M. Berreau, L.M. Regioselec-tive Aliphatic Carbon-Carbon Bond Cleavage by Model System of Relevance to Iron-Contaning Acireductone Dioxygenase. J. Am. Chem. Soc. 2013,135, 659-668. 

The methionine salvage pathway (MSP) plays a critical role in regulating a munber of important metabolites in prokaryotes and eukaryotes. Acireductone dioxygenases (ARDs) Ni(Fe)ARD are enz mies involved in the methionine recycle pathway, which regulates aspects of the cell cycle. The relatively subtle differences between the two metal protein complexes are amplified by the surrounding protein stmcture, giving two enzymes of different stmctures and activities from a single pol eptide [2-5]. 

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