TY - JOUR TI - Bacterial survival in microscopic surface wetness AU - Grinberg, Maor AU - Orevi, Tomer AU - Steinberg, Shifra AU - Kashtan, Nadav A2 - Shou, Wenying A2 - Storz, Gisela A2 - Shou, Wenying A2 - Tecon, Robin VL - 8 PY - 2019 DA - 2019/10/15 SP - e48508 C1 - eLife 2019;8:e48508 DO - 10.7554/eLife.48508 UR - https://doi.org/10.7554/eLife.48508 AB - Plant leaves constitute a huge microbial habitat of global importance. How microorganisms survive the dry daytime on leaves and avoid desiccation is not well understood. There is evidence that microscopic surface wetness in the form of thin films and micrometer-sized droplets, invisible to the naked eye, persists on leaves during daytime due to deliquescence – the absorption of water until dissolution – of hygroscopic aerosols. Here, we study how such microscopic wetness affects cell survival. We show that, on surfaces drying under moderate humidity, stable microdroplets form around bacterial aggregates due to capillary pinning and deliquescence. Notably, droplet-size increases with aggregate-size, and cell survival is higher the larger the droplet. This phenomenon was observed for 13 bacterial species, two of which – Pseudomonas fluorescens and P. putida – were studied in depth. Microdroplet formation around aggregates is likely key to bacterial survival in a variety of unsaturated microbial habitats, including leaf surfaces. KW - plant microbiome KW - phyllosphere KW - desiccation KW - Pseudomonas fluorescens KW - Pseudomonas putida KW - deliquescence JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -