Detection of DOPA 4,5-dioxygenase (DOD) activity using recombinant protein prepared from Escherichia coli cells harboring cDNA encoding DOD from Mirabilis jalapa

Plant Cell Physiol. 2009 May;50(5):1012-6. doi: 10.1093/pcp/pcp053. Epub 2009 Apr 13.


Betalains are synthesized in flowers, fruits and other tissues of the plant order Caryophyllales. Betalamic acid is the chromophore of betalain pigments synthesized by a ring-cleaving enzyme reaction on l-dihydroxyphenylalanine (DOPA). Although reverse genetic evidence has proven that DOPA 4,5-dioxygenase (DOD) is a key enzyme of betalain biosynthesis, all attempts to detect recombinant plant DOD activity in vitro have failed. Here, we report on the formation of betalamic acid from DOPA under suitable assay conditions using recombinant MjDOD produced by Escherichia coli. This is the first report showing biochemical evidence for DOD activity in vitro.

MeSH terms

  • Betalains / metabolism*
  • Cloning, Molecular
  • DNA, Complementary / genetics
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Gene Expression Regulation, Plant
  • Mirabilis / enzymology*
  • Mirabilis / genetics
  • Molecular Sequence Data
  • Oxygenases / genetics
  • Oxygenases / metabolism*
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Pyridines / metabolism*
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism


  • DNA, Complementary
  • Plant Proteins
  • Pyridines
  • Recombinant Proteins
  • betalamic acid
  • Betalains
  • Oxygenases

Associated data

  • GENBANK/AB435372