Abstract
AbstractThe specific association of the potentially plant-pathogenicPseudomonas syringaewithPeltigeralichens raises questions about the factors driving this host specificity. To explore this, the metabolic profile of seven lichen species belonging to three genera (Cladonia, Peltigera, andStereocaulon) was analysed using LC-MSMS. Additionally, we assessed the growth ofP. syringaestrains in media supplemented with extracts from each lichen species. This revealed thatPeltigeraexhibits lower metabolite richness compared to other genera, but shows a higher chemical investment in specific compounds. Growth kinetics showed comparableP. syringaegrowth across lichen-supplemented media, except forC. arbusculaandCladoniasp., where the former exhibited lower growth rates. Inhibition assays with lichen extracts showed no inhibition ofP. syringae. The lichen metabolome is predominantly composed of lipids and organic acids. Furthermore, specific compounds, such as aminoglycosides, may facilitateP. syringaepresence inPeltigeraby inhibitingBacillus subtilisand other antagonists. Additionally, compounds absent inPeltigera, like anthracene, might serve as a carbon source inhibitors likeB. velezensis.
Publisher
Cold Spring Harbor Laboratory