A new enzyme involved in the control of the stereochemistry in the decalin formation during equisetin biosynthesis

Biochem Biophys Res Commun. 2015 May 1;460(2):210-5. doi: 10.1016/j.bbrc.2015.03.011. Epub 2015 Mar 11.

Abstract

Tetramic acid containing a decalin ring such as equisetin and phomasetin is one of the characteristic scaffolds found in fungal bioactive secondary metabolites. Polyketide (PKS)-nonribosomal peptide synthetase (NRPS) hybrid enzyme is responsible for the synthesis of the polyketide scaffold conjugated with an amino acid. PKS-NRPS hybrid complex programs to create structural diversity in the polyketide backbone have begun to be investigated, yet mechanism of control of the stereochemistry in a decalin formation via a Diels-Alder cycloaddition remains uncertain. Here, we demonstrate that fsa2, which showed no homology to genes encoding proteins of known function, in the fsa cluster responsible for equisetin and fusarisetin A biosynthesis in Fusarium sp. FN080326, is involved in the control of stereochemistry in decalin formation via a Diels-Alder reaction in the equisetin biosynthetic pathway.

Keywords: Biosynthesis; Decalin; Diels-Alder cycloaddition; Fusarium PKS-NRPS hybrid; Secondary metabolite.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Fusarium / enzymology
  • Fusarium / genetics
  • Fusarium / metabolism
  • Genes, Fungal
  • Multigene Family
  • Naphthalenes / metabolism*
  • Polyketide Synthases / metabolism*
  • Pyrrolidinones / metabolism*
  • Stereoisomerism
  • Tetrahydronaphthalenes / metabolism*

Substances

  • Naphthalenes
  • Pyrrolidinones
  • Tetrahydronaphthalenes
  • equisetin
  • Polyketide Synthases
  • decalin