Metabarcoding and Metagenomic Characterizations of the Red Sea Sector of the Global Dust Belt’s Microbiome

Atmospheric aerosols have been studied in great depth in regards to its metrological and chemical characterizations. Covering about 33% of the planet, the Global Dust Belt is the major source of wind-blown dust. Airborne aerosols play important roles in the Earth systems, impacting the marine and terrestrial ecosystems, human and organismal health. Aerosolized dust can carry a diverse range of microorganisms that may be transported across large distances. If surviving the transport, influence, as vectors supporting microbial populations or as pathogens to other organisms, the recipient ecosystems where they may be delivered through dry and wet depositions. Located in the middle of the global dust belt area, the Red Sea receives about 1.2 Mt of emitted dust particles per storm and a total of 6 Mt dust deposition from the annual 5-6 storm events, which may contain important loads of microorganisms. This dissertation characterizes the taxonomical compositions of airborne prokaryotes and micro-eukaryotes and their transport history in the dust-associated microbiome, and the functional profile of the airborne microorganisms. The samples required to achieve these goals were collected with a high-volume dust collector over the Red Sea from the coastal and offshore regions over two years. In addition, microbial communities sampled from the surface Red Sea water were used to establish the possible relationship, suggesting an exchange, between the airborne microbial communities and those in the Red Sea. Since relying on culture5 based analyses would take no notice of unculturable microorganism, culture-independent techniques were followed to detect the vast majority of the biological particles on the sampled air filters. However, large volumes of air should be collected due to the difficulty of acquiring enough genomic materials from the low density of airborne microorganisms for molecular assays. Sahara Deserts and deserts in the Arabian Peninsula represented the major sources of microbial inputs to the Red Sea atmosphere. Hence, a high number of allergens, plant and mammalian pathogens, human and animal parasites have been detected in airborne dust samples, which could be of concern. Functionally, dust-associated microbiome has exclusive lifestyle’s features that facilitate a resilient strategy to survive during airborne transportation, so-called “aeolian lifestyle.”