Purification, cloning, functional expression and characterization of perakine reductase: the first example from the AKR enzyme family, extending the alkaloidal network of the plant Rauvolfia

Plant Mol Biol. 2008 Jul;67(5):455-67. doi: 10.1007/s11103-008-9331-7. Epub 2008 Apr 13.


Perakine reductase (PR) catalyzes an NADPH-dependent step in a side-branch of the 10-step biosynthetic pathway of the alkaloid ajmaline. The enzyme was cloned by a "reverse-genetic" approach from cell suspension cultures of the plant Rauvolfia serpentina (Apocynaceae) and functionally expressed in Escherichia coli as the N-terminal His(6)-tagged protein. PR displays a broad substrate acceptance, converting 16 out of 28 tested compounds with reducible carbonyl function which belong to three substrate groups: benzaldehyde, cinnamic aldehyde derivatives and monoterpenoid indole alkaloids. The enzyme has an extraordinary selectivity in the group of alkaloids. Sequence alignments define PR as a new member of the aldo-keto reductase (AKR) super family, exhibiting the conserved catalytic tetrad Asp52, Tyr57, Lys84, His126. Site-directed mutagenesis of each of these functional residues to an alanine residue results in >97.8% loss of enzyme activity, in compounds of each substrate group. PR represents the first example of the large AKR-family which is involved in the biosynthesis of plant monoterpenoid indole alkaloids. In addition to a new esterase, PR significantly extends the Rauvolfia alkaloid network to the novel group of peraksine alkaloids.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alcohol Oxidoreductases / chemistry
  • Alcohol Oxidoreductases / genetics
  • Alcohol Oxidoreductases / isolation & purification*
  • Alcohol Oxidoreductases / metabolism*
  • Aldehyde Reductase
  • Aldo-Keto Reductases
  • Amino Acid Sequence
  • Base Sequence
  • Cloning, Molecular
  • DNA Primers
  • DNA, Complementary
  • Molecular Sequence Data
  • Plant Proteins / chemistry
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Rauwolfia / enzymology*
  • Rauwolfia / metabolism
  • Secologanin Tryptamine Alkaloids / metabolism*
  • Sequence Homology, Amino Acid
  • Substrate Specificity


  • DNA Primers
  • DNA, Complementary
  • Plant Proteins
  • Secologanin Tryptamine Alkaloids
  • Alcohol Oxidoreductases
  • Aldo-Keto Reductases
  • perakine reductase, Rauvolfia serpentina
  • Aldehyde Reductase

Associated data

  • GENBANK/AY766462