Properties relevant to atmospheric dispersal of the ice-nucleation active Pseudomonas syringae strain R10.79 isolated from rain water

AbstractTransport of microbes in the atmosphere allows them to spread and to colonize new habitats. To survive the harsh environmental conditions encountered in the atmosphere, these microorganisms have to possess properties that allow them to resist atmospheric stress. We combined physiological experiments and genome analysis ofPseudomonas syringae strain R10.79, previously isolated from rain, to decipher the strain ’s ability to withstand these challenges and identify the mechanisms behind the resistance. We used laboratory experiments to simulate different atmospheric stress factors and evaluated cell survival using fluorescent staining and flow cytometry. We found that whileP. syringae R10.79 was resistant to oxidative, osmotic, UVB radiation-induced and freezing stress, it was sensitive to desiccation on surfaces. Strain R10.79 possesses a range of genes that would allow the strain to mitigate atmospheric stresses, such as cold shock and osmotic shock genes as well as genes encoding for properties that relate to UV irradiation resistance. Studying the substrate spectrum of strain R10.79, we uncovered that it can utilize carbon compounds abundant in the atmosphere including acetate, succinate and formate. In addition, strain R10.79 possesses metabolic pathways to utilize formaldehyde and methanol as sole carbon sources. These compounds could support the metabolic activity of strain R10.79 while suspended in the atmosphere during periods with sufficiently high relative h...
Source: Aerobiologia - Category: Environmental Health Source Type: research