Campus Units

Biochemistry, Biophysics and Molecular Biology

Document Type

Article

Publication Version

Published Version

Publication Date

4-2017

Journal or Book Title

Molecular Plant-Microbe Interactions

Volume

30

Issue

4

First Page

343

Last Page

349

DOI

10.1094/MPMI-01-17-0001-R

Abstract

Certain plant-associated microbes can produce gibberellin (GA) phytohormones, as first described for the rice fungal pathogen Gibberella fujikuroi and, more recently, for bacteria, including several rhizobia and the rice bacterial pathogen Xanthomonas oryzae pv. oryzicola. The relevant enzymes are encoded by a biosynthetic operon that exhibits both a greater phylogenetic range and scattered distribution among plant-associated bacteria. Here, the phylogenetic distribution of this operon was investigated. To demonstrate conserved functionality, the enzymes encoded by the disparate operon from X. translucens pv. translucens, along with those from the most divergent example, found in Erwinia tracheiphila, were biochemically characterized. In both of these phytopathogens, the operon leads to production of the bioactive GA4. Based on these results, it seems that this operon is widely dedicated to GA biosynthesis. However, there is intriguing variation in the exact product. In particular, although all plant pathogens seem to produce bioactive GA4, rhizobia generally only produce the penultimate hormonal precursor GA9. This is suggested to reflect their distinct interactions with plants, because production of GA4 counteracts the jasmonic-acid-mediated defense response, reflecting the importance of wounds as the entry point for these phytopathogens, whereas such suppression presumably is detrimental in the rhizobial symbiotic relationship.

Comments

This article is published as Nagel, Raimund, and Reuben J. Peters. "Investigating the Phylogenetic Range of Gibberellin Biosynthesis in Bacteria." Molecular Plant-Microbe Interactions 30, no. 4 (2017): 343-349. doi: 10.1094/MPMI-01-17-0001-R. Posted with permission.

Copyright Owner

The American Phytopathological Society

Language

en

File Format

application/pdf

Available for download on Sunday, April 01, 2018

Share

COinS