Structural motifs of syringyl peroxidases predate not only the gymnosperm–angiosperm divergence but also the radiation of tracheophytes
Article first published online: 6 NOV 2006
Volume 173, Issue 1, pages 63–78, January 2007
How to Cite
Ros, L. V. G., Gabaldón, C., Pomar, F., Merino, F., Pedreño, M. A. and Barceló, A. R. (2007), Structural motifs of syringyl peroxidases predate not only the gymnosperm–angiosperm divergence but also the radiation of tracheophytes. New Phytologist, 173: 63–78. doi: 10.1111/j.1469-8137.2006.01898.x
- Issue published online: 6 NOV 2006
- Article first published online: 6 NOV 2006
- Received: 3 July 2006 Accepted: 24 August 2006
- basic peroxidases;
- lignin heterogeneity;
- syringyl moieties;
- Zinnia elegans
- • The most distinctive variation in the monomer composition of lignins in vascular land plants is that found between the two main groups of seed plants. Thus, while gymnosperm lignins are typically composed of guaiacyl (G) units, angiosperm lignins are largely composed of similar levels of G and syringyl (S) units.
- • However, and contrary to what might be expected, peroxidases isolated from basal (Cycadales and Ginkgoales) and differentially evolved (Coniferales and Gnetales) gymnosperms are also able to oxidize S moieties, and this ability is independent of the presence or absence of S-type units in their lignins.
- • The results obtained led us to look at the protein database to search for homologies between gymnosperm peroxidases and true eudicot S-peroxidases, such as the Zinnia elegans peroxidase.
- • The findings showed that certain structural motifs characteristic of eudicot S-peroxidases (certain amino acid sequences and β-sheet secondary structures) predate the gymnosperm–angiosperm divergence and the radiation of tracheophytes, since they are found not only in peroxidases from basal gymnosperms, ferns and lycopods, but also in peroxidases from the moss Physcomitrella patens (Bryopsida) and the liverwort Marchantia polymorpha (Marchantiopsida), which, as typical of bryophytes, do not have xylem tissue nor lignins.