Aerosolization of Two Strains (Ice+ and Ice–) ofPseudomonas syringaein a Collison Nebulizer at Different Temperatures

The aerosolization of microorganisms from aquatic environments is understudied. This article describes a study in which an ice nucleation active (ice+) strain and a nonice nucleation active (ice−) strain of the bacterium Pseudomonas syringae were aerosolized from aqueous suspensions under artificial laboratory conditions using a collison nebulizer. The aerosolization of P. syringae was not influenced by water temperatures between 5° and 30°C. In general, the culturability (viability) of P. syringae in aerosols increased with temperature between 5 and 30°C. The ice+ strain was aerosolized in greater numbers than the ice– strain at all temperatures studied, suggesting a possible connection between the ice nucleation phenotype and aerosol production. Together, our results suggest that P. syringae has the potential to be aerosolized from natural aquatic environments, such as streams, rivers, ponds, and lakes; known reservoirs of P. syringae. Future work is needed to elucidate the mechanisms of aerosolization of P. syringae from natural aquatic systems.