Geosciences Dept. Seminar: Combining Disciplines for Understanding Complex Phenomena: The Impact of Microbial Communities on Health and Environmental Processes

Abstract: 

Microbial communities play an important role in the Earth system, particularly in the interactions between atmosphere, biosphere, climate, and public health. Advances in biological techniques combined with multiphase chemical analyses enable the untangling of such complex mechanisms. In this seminar I will present two studies combining immunological and metagenomic approaches with novel analytical chemistry tools to better understand the involvement of microbial communities in environmental and health related processes.

In the first study we try to gain insights on the clear but unexplained global trend of increased susceptibility to allergies observed in the past decades, by looking at cyanobacteria as unforeseen allergens. Cyanobacteria, globally increasing in biomass due to climate change, industrial usage for biofuel production and food supplements, have been reported to induce allergic reactions, but the current knowledge on the allergenic compounds and the abundance in population is limited. Therefore, we aimed to identify and characterize allergenic potential of cyanobacteria originating from different ecological environments. A variety of cyanobacteria species were tested for their immunoreactivity using different immunological techniques, combined with mass spectrometry analysis. We show similarities in fresh water cyanobacteria sharing phycocyanin, a unique protein in the cyanobacterial photosynthesis system, as a common allergenic compound. We further discuss different IgE-binding characteristics of cyanobacteria originating from marine and soil environments.

The second study focuses on the formation mechanisms of desert varnish, a topic under debate regarding the involvement of microorganisms. The understanding of this process might give insight on the Martian varnished rocks, potentially containing ancient microbes or chemical signature of previous life on Mars. Therefore, in this work we aimed to map the microbial population occurs in rock varnish, and to investigate their role in transition metal oxidation for varnish formation. By combining next generation sequencing analysis with fluorescence and x-ray microscopy, we suggest unique populations and different protein functional groups occurring in the varnish compared to soil samples. Together with mapping the location of the organic compounds in the rock, our results shed light on the mechanism of desert varnish formation.

The two examples open a window for a novel and rapidly growing research area combining tools from chemistry and physics together with advanced biological techniques for a comprehensive understanding of microbial community involvement in public health and the earth system.

Seminar Organizer: Prof. Eyal Haifetz