Plant Molecular Biology

, Volume 47, Issue 5, pp 581–593

The syringaldazine-oxidizing peroxidase PXP 3-4 from poplar xylem: cDNA isolation, characterization and expression

  • Jørgen Holst Christensen
  • Serge Overney
  • Antje Rohde
  • Wilson Ardiles Diaz
  • Guy Bauw
  • Patrice Simon
  • Marc Van Montagu
  • Wout Boerjan
Article

DOI: 10.1023/A:1012271729285

Cite this article as:
Holst Christensen, J., Overney, S., Rohde, A. et al. Plant Mol Biol (2001) 47: 581. doi:10.1023/A:1012271729285

Abstract

The cell wall polymer lignin is believed to be condensed by specific cell wall-localized oxidoreductases. In many plants species, including poplar, the peroxidase-directed oxidation of the lignin analogue syringaldazine (SYR) has been localized to cells that undergo secondary wall formation, a process that includes lignification. As a first step to analyse the corresponding peroxidases, we have isolated previously two anionic isoenzymes (PXP 3-4 and PXP 5) from poplar xylem (Populustrichocarpa), which use SYR as a substrate. Here, we demonstrate that these enzymes are responsible for the visualized SYR oxidation in the developing xylem. The cDNA that corresponds to PXP 3-4 was isolated and the deduced protein was found closely related to the other SYR-oxidizing peroxidase PXP 5 (ca. 98% of identity). PXP 3-4 was expressed in a baculovirus expression system yielding high levels of active peroxidase (3 mg/l medium). The heterologously produced protein showed characteristics similar to those of the corresponding protein from poplar xylem (enzymatic properties, isoelectric point, and migration in a native gel). PXP 3-4 was expressed in the stem and in the root xylem. The data demonstrate that PXP 3-4 (and/or PXP 5) are present in differentiating xylem, supporting a function in secondary cell wall formation.

cDNA isolationexpression analysislignificationpoplar xylem peroxidasesecondary cell wall formationsyringaldazine oxidation

Copyright information

© Kluwer Academic Publishers 2001

Authors and Affiliations

  • Jørgen Holst Christensen
    • 1
  • Serge Overney
    • 2
  • Antje Rohde
    • 1
  • Wilson Ardiles Diaz
    • 1
  • Guy Bauw
    • 1
  • Patrice Simon
    • 2
  • Marc Van Montagu
    • 1
  • Wout Boerjan
    • 1
  1. 1.Vakgroep Moleculaire Genetica, Departement Plantengenetica, Vlaams Interuniversitair Instituut voor Biotechnologie (VIB)Universiteit GentGentBelgium
  2. 2.Plant Biochemistry and PhysiologyUniversity of GenevaGenève 4Switzerland