Bacterial Microbiome GG 2017
Lichens are among the few organisms capable of thriving in extreme environments, forming miniature ecosystems composed of diverse fungal, algal, and bacterial communities. To under-stand their adaptation mechanisms along climatic gradients, the composition, distribution, and interactions of their primary symbiotic partners (mycobiont [fungus]/ photobiont [algae]) and the bacterial microbiomes were studied. Using molecular techniques, including Sanger and high-throughput amplicon sequencing, we analyzed saxicolous lichens along an elevational gradient (1168-2562 m a.s.l.) in the Grossglockner region, Salzburg, Austria. The following research questions were addressed: (i) Do the symbiotic partners of lichens – mycobionts, photobionts, and bacterial communities – vary in composition and diversity along an elevational gradient? (ii) Do the neighboring lichens share locally available symbiotic part-ners, such as photobionts, and bacterial microbiomes? All three partners of lichen communities, i.e. mycobionts, photobionts, and bacteria, varied in diversity and composition along the elevational gradient. Neighboring lichens within microhabi-tats shared photobionts, indicating local availability as a key factor in partner selection. Howev-er, bacterial microbiomes showed substantial heterogeneity across and within sites, influenced by mycobiont-photobiont interactions. The formation of local guilds drives new symbiotic com-binations that may improve the adaptability of lichens to environmental changes and the coloni-zation of new niches.