Selective inhibition of Erwinia amylovora by the herbicidally active germination-arrest factor (GAF) produced by Pseudomonas bacteria
Article first published online: 4 AUG 2011
Journal of Applied Microbiology © 2011 The Society for Applied Microbiology. No claim to US Government works
Journal of Applied Microbiology
Volume 111, Issue 4, pages 949–959, October 2011
How to Cite
Halgren, A., Azevedo, M., Mills, D., Armstrong, D., Thimmaiah, M., McPhail, K. and Banowetz, G. (2011), Selective inhibition of Erwinia amylovora by the herbicidally active germination-arrest factor (GAF) produced by Pseudomonas bacteria. Journal of Applied Microbiology, 111: 949–959. doi: 10.1111/j.1365-2672.2011.05098.x
- Issue published online: 13 SEP 2011
- Article first published online: 4 AUG 2011
- Accepted manuscript online: 4 JUL 2011 12:39PM EST
- 2011/0485: received 22 March 2011, revised 27 June 2011 and accepted 28 June 2011
- aminooxyacetic acid;
- Erwinia amylovora;
- fire blight;
- germination-arrest factor;
- Pseudomonas fluorescens WH6
Aims: The germination-arrest factor (GAF) produced by Pseudomonas fluorescens WH6, and identified as 4-formylaminooxyvinylglycine, specifically inhibits the germination of a wide range of grassy weeds. This study was undertaken to determine whether GAF has antimicrobial activity in addition to its inhibitory effects on grass seed germination.
Methods and Results: Culture filtrate from Ps. fluorescens WH6 had little or no effect on 17 species of bacteria grown in Petri dish lawns, but the in vitro growth of Erwinia amylovora, the causal agent of the disease of orchard crops known as fire blight, was strongly inhibited by the filtrate. The anti-Erwinia activity of WH6 culture filtrate was shown to be due to its GAF content, and a commercially available oxyvinylglycine, 4-aminoethoxyvinylglycine (AVG), exhibited anti-Erwinia activity similar to that of GAF. The effects of GAF on Erwinia were reversed by particular amino acids.
Conclusions: The biological properties of GAF include a rather specific antimicrobial activity against Erw. amylovora. This may be a general property of oxyvinylglycines as AVG exhibited similar activity. The ability of particular amino acids to reverse GAF inhibition is consistent with a potential effect of this compound on the activity of aminotransferases.
Significance and Impact of the Study: The results presented here demonstrate a novel antimicrobial activity of oxyvinylglycines and suggest that GAF and/or GAF-producing bacteria may have potential for the control of fire blight.