TITLE:
The PafR Gene Is Required for Antifungal Activity of Strain MS82 against Mycogone perniciosa
AUTHORS:
Lin Ma, Xiaoqiang Wang, Peng Deng, Sonya M. Baird, Youzhou Liu, Shaoxuan Qu, Shi-En Lu
KEYWORDS:
Pseudomonas fluorescens, Antifungal Activity, Mycogone perniciosa, Mutagenesis
JOURNAL NAME:
Advances in Microbiology,
Vol.7 No.4,
April
14,
2017
ABSTRACT: Bacterial strain MS82, isolated from the rhizosphere of a soybean plant, belongs to the species Pseudomonas fluorescens. The most important feature of strain MS82 is the production of antifungal activity against the mushroom pathogenic fungus Mycogone perniciosa but not against the mushroom fungus Agaricus bisporus. In this study, the mutant MS82MT19 generated with the EZ-Tn5 transposon system completely lost the antifungal activity against M. perniciosa. An open-reading frame named as PafR and predicted to code for a sensory box GGDEF/EAL domain protein, was disrupted in MS82MT19. To further confirm the function of this gene, site-directed mutagenesis with insertion of the terminatorless nptII cassette into the PafR gene was used to generate the mutant MS82SD19. As expected, there was no detectable antifungal activity of mutant MS82SD19 against M. perniciosa. These results suggest that the PafR gene plays an important role in the production of antifungal activity of P. fluorescens strain MS82.