Flavodiiron protein

It has been suggested that an FeS flavoprotein with presumed electron transporting function may be involved in the reduction of the flavodiiron protein in Methanosarcina acetivorans (Saraiva et al. 2004). Since putative FeS flavoproteins with predicted hydrogenosomal target peptides have also... 

Saraiva LM, Vicente JB, Teixeira M (2004) The role of the flavodiiron proteins in microbial nitric oxide detoxification. Adv Microb Physiol 49 77-129 Schirch V, Szebenyi DME (2005) Serine hydroxymethyltransferase revisited. Curr Opin Chem Biol 9 482-487... 

Another novel candidate with NO reductase activity is a flavodiiron protein from Moorella thermoacetica [114]. Two genes of this strictly anaerobic, aceto-genic bacterium, namely and hrb, have no known function. FprA contains flavin mononucleotide (FMN) and a non-heme diiron site while Hrb contains FMN and a rubredoxin-like [Fe(SCys)4] site. The combination of Hrb and FprA exhibits NADH NO oxidoreductase activity. 

Figure 7 Structures of the active site of flavodiiron proteins that act as NO reductases (left) and the [ FeNOl b model complex [Fe2(BPMP)(OPr)(NO)2l(BPh4)2 (dication of 18) (right).

Rodrigues R, Vicente JB, Felix R, Oliveira S, Teixeira M, Rodrigues-Pousada C. 2006. Desulfovibrio gigas flavodiiron protein affords protection against nitrosative stress in vivo. J Bacterial 188 2745-2751. 

Silaghi-Dumitrescu R, Coulter ED, Das A, Ljungdahl LG, Jameson GNL, Huynh BH, Kurtz Jr DM. 2003. A flavodiiron protein and high molecular weight mbredoxin from Moorella thermoacetica with nitric oxide reductase activity. Biochemistry 42 2806-2815. 

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