Abstract
We performed a growth inhibition assay to test antibacterial compounds in leaf extracts from transgenic rice plants. The assay is based on over-night co-incubation of a defined concentration of colony forming units (cfu) of the respective bacteria together with aqueous extracts of ground leaf tissue.
Keywords: Crop plant, Rice, Pathogen, Bacteria, Antimicrobial, Jacalin, Lectin, Dirigent
Background
Defense of plants against harmful organisms can be specific against particular pathogen species or groups of pathogens. Aiming at increasing pathogen resistance of crop plants, breeding for resistance against particular diseases can be useful but the ultimate goal is to implement broad-spectrum disease resistance. The rice protein OsJAC1 is a modular protein consisting of a jacalin-related lectin domain predicted to bind to sugar residues and a dirigent domain that might act during coupling of monolignols. This fusion protein is specific to Poaceae and represents a novel type of resistance protein. The protocol described here was used to assess the antimicrobial capabilities of leaf extracts from transgenic rice plants overexpressing the OsJAC1 cDNA (Weidenbach et al., 2016). For this assay, the bacterial lab strain Escherichia coli K12 and the bacterial rice pathogen Xanthomonas oryzae pv. oryzae PXO86, causing bacterial blight, were used.
Materials and Reagents
Equipment
Procedure
Notes:
Data analysis
Calculate mean value and standard deviation of the number of cfu on the triplicate plates. The number of cfu of the wild-type sample is set to 100%. Test for significant reduction of bacterial growth in sample compared to control by applying Student’s t-test.
Notes
Recipes
Acknowledgments
Protocol based on methods described in Weidenbach et al. (2016). DW was funded in the framework of the BMBF funding activity ‘Plant Biotechnology for the future, PLANT 2030’ within the project ‘BarleyFortress’.
References
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