DISSERTATION RESEARCH: A phylogenetic characterization of the lichen microbiome

Duke University, Durham NC

Investigators

Abstract

Lichens are biological associations comprised of a fungus (mycobiont) and an alga and/or cyanobacterium (photobiont). Certain lichens have been shown to host diverse communities of bacteria that are not photobionts, though these communities are very poorly known. Many lichens are able to grow to large sizes in very nutrient-poor habitats such as rock outcrops. This observation supports the notion that members of the lichen-associated bacterial community may provide the lichen with crucial nutrients (e.g., fixed nitrogen) that otherwise would be unavailable. The main objectives of this study are to conduct the first large-scale survey of bacteria associated with lichens and to determine what role nitrogen requirements play in determining the composition of these bacterial communities. The data generated as part of this study will reveal additional new lineages of microorganisms and contribute to the general understanding of bacterial diversity. The examination of these microbial communities may also shed light on the evolution of interactions among bacteria and the organisms that comprise lichens. In conjunction with this project, the funded graduate student will lead local 'lichen walks' to educate the public. Additionally, websites will be generated and maintained in order to make research findings accessible to all.