Atmospheric dispersal shapes rapid bacterial colonization of Icelandic Lava Rocks.

Microorganisms released into the atmosphere by various disturbances can travel significant distances before depositing, yet their impact on community assembly remains unclear. To address this, we examined atmospheric and lithospheric bacterial communities in 179 samples collected at two distinct Icelandic volcanic sites: a small volcanic island Surtsey, and a volcanic highland Fimmvörðuháls using 16S rRNA amplicon sequencing. Airborne microbial communities were similar between sites while significant differences emerged in the communities on lava rocks after 1-year exposure.

Survival of Icelandic airborne microbes towards simulated atmospheric stress factors.

Surface microbes are aerosolized into the atmosphere by wind and events such as dust storms, wildland fires, and volcano eruptions. Only microbial cells that survive the various atmospheric stressors during their transportation will deposit and colonize new environments. These stressors include desiccation, oxidative stress, solar radiation, osmotic shock, and freeze-thaw cycles.

Comparison of Atmospheric and Lithospheric Culturable Bacterial Communities from Two Dissimilar Active Volcanic Sites, Surtsey Island and Fimmvörðuháls Mountain in Iceland.

Surface microbes are aerosolized into the atmosphere by wind and events such as dust storms and volcanic eruptions. Before they reach their deposition site, they experience stressful atmospheric conditions which preclude the successful dispersal of a large fraction of cells. In this study, our objectives were to assess and compare the atmospheric and lithospheric bacterial cultivable diversity of two geographically different Icelandic volcanic sites: the island Surtsey and the Fimmvörðuháls mountain, to predict the origin of the culturable microbes from these sites, and to select airborne candidates for further investigation.

Pelagibaculum spongiae gen. nov., sp. nov., isolated from a marine sponge in South-West Iceland.

A Gram-stain-negative, motile, mesophilic, aerobic, rod-shaped bacterium, designated Hp12, was isolated from a marine sponge in the intertidal zone off the coast of Seltjarnarnes (64° 16' N 22° 00' W), Iceland. Strain Hp12 grew optimally at 20-22 °C, at pH 7-8 and in the presence of 1-2 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences placed strain Hp12 in the class Gammaproteobacteria, related to members of the genus Alcanivorax in the order Oceanospirillales with 90.