Upregulation of MAP kinase HOG1 gene of white-rot fungus Phlebia sp. MG-60 inhibits the ethanol fermentation and mycelial growth

Biosci Biotechnol Biochem. 2023 Jan 24;87(2):217-227. doi: 10.1093/bbb/zbac203.

Abstract

Wood biomass conversion for fossil resource replacement could result in the sustainable production of chemicals, although lignin represents an obstacle to efficient polysaccharide use. White-rot fungus Phlebia sp. MG-60 reportedly selectively and aerobically degrades lignin in hardwood, then it begins cellulose saccharification from the delignified wood to produce ethanol. Environmental conditions might change white-rot fungi-driven biomass conversion. However, how the environmental response sensor affects ethanol fermentation in white-rot fungi remains elusive. In this study, we focused on MGHOG1, the yeast Hog1 homolog in Phlebia sp. MG-60, a presumably important player in osmoresponse. We generated MGHOG1 overexpressing (OE) transformants in Phlebia sp. MG-60, exhibiting slower mycelial growth compared with the wild-type under salinity stress. MGHOG1 overexpressing liquid cultures displayed suppressed mycelial growth and ethanol fermentation. Therefore, MGHOG1 potentially influences ethanol fermentation and mycelial growth in Phlebia sp. MG-60. This study provides novel insights into the regulation of white-rot fungi-mediated biomass conversion.

Keywords: Hog1; TCA cycle; ethanol fermentation; metabolic change; white-rot fungi.

MeSH terms

  • Basidiomycota* / metabolism
  • Ethanol / metabolism
  • Fermentation
  • Lignin
  • Mitogen-Activated Protein Kinases / metabolism
  • Polyporales*
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins* / genetics
  • Up-Regulation

Substances

  • Lignin
  • Ethanol
  • HOG1 protein, S cerevisiae
  • Mitogen-Activated Protein Kinases
  • Saccharomyces cerevisiae Proteins

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