Conservation of fungal and animal nicotinamide adenine dinucleotide phosphate oxidase complexes. Issue 6 (23rd February 2015)

• Record Type: Journal Article
• Authors: Scott, Barry
• Is Part Of: Molecular microbiology. Volume 95:Issue 6(2015)
• Page Start: 910
• Page End: 913
• Publication Date: 2015-02-23
• Subjects: Molecular microbiology -- Periodicals; 572.829
• DOI: 10.1111/mmi.12946
• Languages: English
• ISSNs: 0950-382X

Abstract

<abstract abstract-type="main"> <title>Summary</title> <p>Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (Nox) are a group of eukaryotic flavoenzymes that catalyse the reduction of dioxygen to the superoxide anion using electrons provided by NADPH. An integral membrane flavocytochrome b558 heterodimer, composed of the catalytic subunit gp91<italic><sup>phox</sup></italic> and the adaptor protein p22<italic><sup>phox</sup></italic>, is essential for catalytic activity of the mammalian Nox2 complex. Two homologues of the mammalian gp91<italic><sup>phox</sup></italic>, NoxA and NoxB, have been identified in fungi and shown to be crucial for distinct fungal cell differentiation and developmental processes, but to date, no homologue of the p22<italic><sup>phox</sup></italic> adaptor protein has been identified. Isolation of a mutant from <italic>P</italic><italic>odospora anserina</italic> with a phenotype identical to a previously characterised <italic>PaNox1</italic> mutant, combined with phylogenetic analysis, identified a fungal homologue of p22<italic><sup>phox</sup></italic> called <italic>PaNoxD</italic>. The same adaptor protein was shown to be a component of the <italic>B</italic><italic>otrytis cinerea</italic> NoxA complex as supported by the identical phenotypes of the <italic>bcnoxA</italic> and <italic>bcnoxD</italic> mutants and direct physical interaction between BcNoxA and BcNoxD. These results suggest that NoxA/NoxD is the fungal equivalent of the mammalian gp91<italic><sup>phox</sup></italic>/p22<italic><sup>phox</sup></italic> flavocytochrome complex. Tetraspanin (Pls1) mutants of <italic>P</italic><italic>. anserina</italic> and <italic>B</italic><italic>. cinerea</italic> have identical phenotypes to <italic>noxB</italic> mutants, suggesting that Pls1 is the corresponding integral membrane adaptor for assembly of the NoxB complex.</p> </abstract>