Novel regulatory mechanism of serine biosynthesis associated with 3-phosphoglycerate dehydrogenase in Arabidopsis thaliana

Sci Rep. 2017 Jun 14;7(1):3533. doi: 10.1038/s41598-017-03807-5.


The proteinogenic amino acid L-serine is a precursor for various essential biomolecules in all organisms. 3-Phosphoglycerate dehydrogenase (PGDH) is the first committed enzyme of the phosphorylated pathway of L-serine biosynthesis, and is regulated by negative feedback from L-serine in bacteria and plants. In the present study, two Arabidopsis PGDH isoforms were inhibited by L-serine but were activated by L-amino acids such as L-homocysteine in vitro. Activation and inhibition by these amino acids was cooperative, suggesting an allosteric mechanism. Moreover, the half maximal effective concentration of L-homocysteine was 2 orders of magnitude lower than that of L-serine, suggesting greater regulatory potency. These are the first data to show that PGDH is activated by various biomolecules and indicate that serine biosynthesis is regulated by multiple pathways.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Allosteric Regulation
  • Arabidopsis / enzymology*
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / metabolism*
  • Enzyme Activators / metabolism
  • Enzyme Inhibitors / metabolism
  • Gene Expression Regulation, Enzymologic*
  • Gene Expression Regulation, Plant*
  • Phosphoglycerate Dehydrogenase / metabolism*
  • Serine / biosynthesis*


  • Arabidopsis Proteins
  • Enzyme Activators
  • Enzyme Inhibitors
  • Serine
  • D-3-phosphoglycerate dehydrogenase, Arabidopsis
  • Phosphoglycerate Dehydrogenase