Survival and ice nucleation activity of Pseudomonas syringae strains exposed to simulated high-altitude atmospheric conditions

Autor(es)

de Araujo, Gabriel Guarany ^[1] ; Rodrigues, Fabio ^[2] ; Teixeira Goncalves, Fabio Luiz ^[3] ; Galante, Douglas ^[4]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Interun Grad Program Biotechnol, Ave Prof Lineu Prestes 2415, BR-05508900 Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, Dept Fundamental Chem, Inst Chem, Ave Prof Lineu Prestes 748, BR-05508000 Sao Paulo, SP - Brazil

^[3] Univ Sao Paulo, Dept Atmospher Sci, Inst Astron Geophys & Atmospher Sci, Rua Matao 1226, BR-05508090 Sao Paulo, SP - Brazil

^[4] Brazilian Ctr Res Energy & Mat, Brazilian Synchrotron Light Lab, Ave Giuseppe Maximo Scolfaro 10000, BR-13083100 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: SCIENTIFIC REPORTS; v. 9, MAY 23 2019.
• Citações Web of Science: 2

Resumo

Pseudomonas syringae produces highly efficient biological ice nuclei (IN) that were proposed to influence precipitation by freezing water in clouds. This bacterium may be capable of dispersing through the atmosphere, having been reported in rain, snow, and cloud water samples. This study assesses its survival and maintenance of IN activity under stressing conditions present at high altitudes, such as UV radiation within clouds. Strains of the pathovars syringae and garcae were compared to Escherichia coli. While UV-C effectively inactivated these cells, the Pseudomonas were much more tolerant to UV-B. The P. syringae strains were also more resistant to radiation from a solar simulator, composed of UV-A and UV-B, while only one of them suffered a decline in IN activity at -5 degrees C after long exposures. Desiccation at different relative humidity values also affected the IN, but some activity at -5 degrees C was always maintained. The pathovar garcae tended to be more resistant than the pathovar syringae, particularly to desiccation, though its IN were found to be generally more sensitive. Compared to E. coli, the P. syringae strains appear to be better adapted to survival under conditions present at high altitudes and in clouds. (AU)

• Processo FAPESP: 12/18936-0 - Aplicações de Espectroscopia Raman em paleobiologia e astrobiologia
• Beneficiário: Setembrino Petri
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 16/06160-8 - Amostragem e modelagem de aerossóis biogênicos primários no Sul-Sudeste do Brasil: associado às melhorias de modelos climáticos
• Beneficiário: Fabio Rodrigues
• Modalidade de apoio: Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Temático