Enhanced hypocrellin production of Shiraia sp. SUPER-H168 by overexpression of alpha-amylase gene

PLoS One. 2018 May 3;13(5):e0196519. doi: 10.1371/journal.pone.0196519. eCollection 2018.

Abstract

Relative expression levels of twenty-four amylase genes in Shiraia sp. SUPER-H168 were investigated by real-time quantitative PCR when various carbohydrates, including glucose, sucrose, maltose, amylose, amylopectin and corn flour, were used as carbon source. Genes, including an α-glucosidase gene Amy33 (2997 bp), an α-amylase gene Amy365-1 (1749 bp) and a glycogen debranching enzyme gene Amy130 (2487 bp), were overexpressed, and four overexpression transformants were constructed, respectively. When Amy365-1 and Amy130 were co-overexpressed, relative expression levels of seven hypocrellin biosynthesis genes and four related genes in central carbon catabolism were all increased. Expression of Amy33 was also increased along with increase of Amy365-1 and Amy130. Under liquid state fermentation, biomasses and hypocrellin productions were both gradually increased in four overexpression strains than those of wild type strain. Under SSF, hypocrellin production of Amy365-1 and Amy130 co-expression strain reached 71.85 mg/gds, which was 2.83 fold than that of wild type strain, and residual sugar was decreased from 35.47% to 16.68%. These results can provide a practical approach for other secondary metabolites by filamentous fungi under SSF when raw starch material is used as carbon source.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ascomycota / enzymology
  • Ascomycota / genetics*
  • Ascomycota / metabolism*
  • Biosynthetic Pathways
  • Cloning, Molecular
  • DNA, Fungal / genetics
  • Fermentation
  • Fungal Proteins / genetics*
  • Fungal Proteins / metabolism*
  • Genes, Fungal
  • Glucose / metabolism
  • Perylene / analogs & derivatives*
  • Perylene / metabolism
  • Phenol
  • Photosensitizing Agents / metabolism*
  • Quinones / metabolism*
  • Up-Regulation
  • alpha-Amylases / genetics*
  • alpha-Amylases / metabolism*

Substances

  • DNA, Fungal
  • Fungal Proteins
  • Photosensitizing Agents
  • Quinones
  • Phenol
  • Perylene
  • alpha-Amylases
  • Glucose
  • hypocrellin A

Grants and funding

This work was financially supported by the National Science Foundation of China (Grant No. 21275066), fundamental research of doctor of philosophy at 2014 (Grant No. 2050205), Project of Graduate Student Scientific Research and Innovation of Jiangsu province at 2015 (Grant No. 205020502), Six Talent Peak Program at 2016 (Grant No. SWYY-126).