Official websites use. Share sensitive information only on official, secure websites. Crude aqueous extracts from Arabidopsis leaves were subjected to chromatographic separations, after which the different fractions were monitored for antimicrobial activity using the fungus Neurospora crassa as a test organism.
Two major fractions were obtained that appeared to have the same abundance in leaves from untreated plants versus leaves from plants challenge inoculated with the fungus Alternaria brassicicola. This compound has previously been described as a product of myrosinase-mediated breakdown of glucoraphanin, the predominant glucosinolate in Arabidopsis leaves.
A previously identified glucosinolate biosynthesis mutant, gsm , was found to be largely deficient in either of the two major antimicrobial compounds, including 4-methylsulphinylbutyl ITC. The resistance of gsm was compared with that of wild-type plants after challenge with the fungi A. Of the tested pathogens, only F.
Taken together, our data suggest that glucosinolate-derived antimicrobial ITCs can play a role in the protection of Arabidopsis against particular pathogens. Living plants are under constant assault by microbial pathogens trying to gain access to the nutrients sequestered in plant tissues. To deter such potential pathogens, plants have evolved a complex set of defense mechanisms, of which some are preformed and others inducible.
The former mechanisms are in place irrespective of whether or not the plant tissue is challenged by microorganisms, whereas the latter are activated in response to microbial attack. Arabidopsis has emerged since the early s as the leading model for the study of plant defense responses at the molecular level Buell, In this plant three different genetic programs have been identified that are activated upon pathogen recognition leading to the production of inducible antimicrobial compounds.
