Progress 10/01/20 to 09/30/21
Outputs
Target Audience:The target audience is the general research community including NC members and participants at the Asilomar Fungal Genetics and American Phytopathological Society meetings. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?This was the second year of the COVID-19 pandemic, which still precluded travel to meetings. Still, all of my students presented their work at a local meeting in person. Also, my student Nandhitha Venkatesh graduated in August 2021 and has started a job with industry, Mycoworks. How have the results been disseminated to communities of interest?We submitted three manuscripts last year and all are now accepted What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
We have had major advances in our work with the publication/acceptance of three manuscripts. We have focused on the interaction of the wilt bacteriums Ralstonia solanacearum with mycotoxigenic fungi. In a paper published in Microorganisms, we explored the consequences of mixed infection in tomato disease by the wilt pathogens R. solanacearum and Fusarium oxysporum f. sp. lycopersici. Although both pathogens occupy the xylem, the costs of mixed infections on wilt disease are unknown. Our results demonstrate that bacterial wilt severity is reduced in co-infections, that synthesis of the mycotoxin bikaverin by Fusarium contributes to bacterial wilt reduction and that the arrival time of each microbe at the infection court is important in driving severity of wilt disease. Further, analysis of the co-infection root secretome identified previously uncharacterized secreted metabolites that reduce R. solanacearum growth in vitro and provide protection to tomato seedlings against bacterial wilt disease. Taken together, these results highlight the need to understand the consequences of mixed infections in plant disease. In a manuscript published in Current Biology, we examined the hypothesis that specialized fungal survival structures, chlamydospores, induced by bacterial lipopeptides serve as bacterial reservoirs. We find that symbiotic and pathogenic gram-negative bacteria from non-endosymbiotic taxa enter and propagate in chlamydospores. Internalized bacteria have higher fitness than planktonic bacteria when challenged with abiotic stress. Further, tri-cultures ofRalstonia solanacearum, Pseudomonas aeruginosa,and Aspergillus flavus reveal the unprecedented finding that chlamydospores are colonized by endofungal bacterial communities. Our work identifies a previously unknown ecological role of chlamydospores, provides an expanded view of microbial niches, and presents significant implications forthe persistence of pathogenic and beneficial bacteria.
Publications
- Type:
Journal Articles
Status:
Accepted
Year Published:
2022
Citation:
Eagan JL, Steffan BN, Ortiz SC, Drott M, Goldman GH, Hull CM, Keller NP and Bastos RW. (2022) Inadvertent selection of a pathogenic fungus highlights areas of concern in human clinical practices. J. Fungi. 8(2), 157; https://doi.org/10.3390/jof8020157
- Type:
Journal Articles
Status:
Accepted
Year Published:
2022
Citation:
Venkatesh N, Greco C, Drott MT, Koss MJ, Ludwikoski L, Keller NM, Keller NP (2022) Bacterial hitchhikers derive benefits from fungal housing. Current Biol. Accepted
- Type:
Journal Articles
Status:
Published
Year Published:
2021
Citation:
Venkatesh N, Koss MJ, Greco C, Nickles G, Wiemann P, Keller NP (2021) Secreted secondary metabolites reduce bacterial wilt severity of tomato in bacterial-fungal co-infections. Microorganisms 9(10):2123. doi: 10.3390/microorganisms9102123.
|