title: Involvements of S-nitrosylation and denitrosylation in the production of polyphenols by Inonotus obliquus.
abstract: Nitric oxide (NO) has been evidenced to mediate biosynthesis of polyphenols in Inonotus obliquus. However, it remains unknown how NO regulates their biosynthesis. Here we show that higher cellular NO levels coincided with higher accumulation of S-nitrosothiols (SNO; the products of NO combined with a specific residue in glutathione or proteins) and polyphenols, and higher activity of denitrosylated S-nitrosoglutathione reductase (GSNOR) and thioredoxin reductase (TrxR). This homeostasis was breached by GSNOR or TrxR inhibitors. Inhibiting GSNOR boosted TrxR activity, but reduced SNO formation, coinciding with an enhanced production of polyphenols. Likewise, inhibiting TrxR increased GSNOR activity and SNO production, but downregulated accumulation of polyphenols. Inhibiting GSNOR or TrxR also modified the polyphenolic profiles of I. obliquus. Suppressing GSNOR-enhanced biosynthesis of phelligridins C and H, inoscavin C and methyl inoscavin B, but reduced that of phelligridin D, methyl inoscavin A, davallialactone and methyl davallialactone, the typical polyphenols in I. obliquus. Similarly, downregulating TrxR increased production of phelligridin D, methyl inoscavin A, davallialactone, and methyl davallialactone, but shrinking that of phelligridins C and H, methyl inoscavin B and inoscavin C. Thus, in I. obliquus, the state of S-nitrosylation and denitrosylation affects not only the accumulation of polyphenols, but also their metabolic profiles.
authors.affiliation: Key Laboratory for Biotechnology on Medicinal Plants of Jiangsu Province, Xuzhou Normal University, Xuzhou, China. yyzw@xznu.edu.cn
authors.forename: Weifa
authors.initials: W
authors.lastname: Zheng
authors.forename: Yubing
authors.initials: Y
authors.lastname: Liu
authors.forename: Shenyuan
authors.initials: S
authors.lastname: Pan
authors.forename: Weihua
authors.initials: W
authors.lastname: Yuan
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Dai
authors.forename: Jiangchun
authors.initials: J
authors.lastname: Wei
mesh_terms: D000445:Aldehyde Oxidoreductases / Q000235:genetics / Q000378:metabolism; D001487:Basidiomycota / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D005419:Flavonoids / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D010636:Phenols / Q000378:metabolism*; D059808:Polyphenols; D026403:S-Nitrosothiols / Q000378:metabolism*; D013880:Thioredoxin-Disulfide Reductase / Q000235:genetics / Q000378:metabolism
chemical_list: D005419:Flavonoids; D005656:Fungal Proteins; D010636:Phenols; D059808:Polyphenols; D026403:S-Nitrosothiols; D009569:Nitric Oxide; D000445:Aldehyde Oxidoreductases; C087006:formaldehyde dehydrogenase, glutathione-independent; D013880:Thioredoxin-Disulfide Reductase