Cloning and Characterization of Filamentous Fungal S-Nitrosoglutathione Reductase from Aspergillus nidulans.
S-Nitrosoglutathione reductase (GSNOR) metabolizes S-nitrosoglutathione (GSNO) and has been shown to play important roles in regulating cellular signaling and formulating host defense by modulating intracellular nitric oxide levels. The enzyme has been found in bacterial, yeast, mushroom, plant, and mammalian cells. However, to date, there is still no evidence of its occurrence in filamentous fungi. In this study, we cloned and investigated a GSNOR-like enzyme from the filamentous fungus Aspergillus nidulans. The enzyme occurred in native form as a homodimer and exhibited low thermal stability. GSNO was an ideal substrate for the enzyme. The apparent Km and kcat values were 0.55 mM and 34,100 min(-1), respectively. Substrate binding sites and catalytic center amino acid residues based on those from known GSNORs were conserved in this enzyme, and the corresponding roles were verified using site-directed mutagenesis. Therefore, we demonstrated the presence of GSNOR in a filamentous fungus for the first time.
['Zhou|Yao|Y|', 'Zhou|Shengmin|S|', 'Yu|Haijun|H|', 'Li|Jingyi|J|', 'Xia|Yang|Y|', 'Li|Baoyi|B|', 'Wang|Xiaoli|X|', 'Wang|Ping|P|']
D000445:Aldehyde Oxidoreductases D000595:Amino Acid Sequence D001233:Aspergillus nidulans D001483:Base Sequence D001665:Binding Sites D003001:Cloning, Molecular D018076:DNA, Complementary D004926:Escherichia coli D016297:Mutagenesis, Site-Directed D009569:Nitric Oxide D015538:Nitrosation D010802:Phylogeny D011994:Recombinant Proteins D026422:S-Nitrosoglutathione D017422:Sequence Analysis, DNA
S-nitrosoglutathione reductase Aspergillus nidulans nitric oxide denitrosation nitrosation