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Accueil du site > Teams > Biocatalysis & Metabolism > METAbolism > Microbial metabolism in clouds

Microbial metabolism in clouds

All the versions of this article: English , français

The puy de Dôme station, a sampling site for clouds: The puy de Dôme station is labelled as a GAW (Global Atmosphere Watch) station. Cloud water is collected at the top of this mountain with cloud droplet samplers and analyzed for its microbial and chemical content (http://wwwobs.univ-bpclermont.fr/SO...). The laboratory has now a unique microbial bank of about 1000 isolates from clouds.

References :

M. VAÏTILINGOM, E. ATTARD, N. GAIANI, M. SANCELME, L. DEGUILLAUME, A. I. FLOSSMANN, P. AMATO, A.-M. DELORT. Long-term features of cloud microbiology at the puy de Dôme (France). Atmospheric Environment, 2012, 56, 88-100.
L. DEGUILLAUME, T. CHARBOUILLOT, M. JOLY, M. VAÏTILINGOM, M. PARAZOLS, A. MARINONI, P. AMATO, A.-M. DELORT, V. VINATIER, A. FLOSSMANN, N. CHAUMERLIAC, J.-M. PICHON, S. HOUDIER, P. LAJ, K. SELLEGRI, A. COLOMB, M. BRIGANTE, G. MAILHOT. Classification of clouds sampled at the puy de Dôme (France) from 10-year monitoring : Mean features of their physico-chemical properties. Atmospheric Chemistry and Physics, 2014, 14, 1485-1506.

Role of the micro-organisms living in clouds in atmospheric chemistry: Aim: to characterize microbial activity in clouds in order to evaluate its impact on the chemical reactivity of these environments and on biogeochemical cycles. The interactions between micro-organisms recovered from cloud water and some of the key chemical species involved in atmospheric chemistry: free radical (hydroxides OH●, superoxides O2●- and nitrates NO3●) and their precursors (H2O2, iron, organic complexes) as well as iron organic ligands from biological origin (siderophores…) are studied.

Cloud water microcosms incubated under controlled conditions in the laboratory
Production of pyoverdin, a fluorescent siderophore, by a bacteria isolated from cloud water collected at the puy de Dôme station

References :

M. VAÏTILINGOM, L. DEGUILLAUME, V. VINATIER, M. SANCELME, P. AMATO, N. CHAUMERLIAC, A-M DELORT Potential impact of microbial activity on the oxidant capacity and organic carbon budget in clouds. Proceedings of the National Academy of Science USA, 2013, 110, 559-564.

M. MATULOVA, S. HUSAROVA, P. CAPEK, M. SANCELME, A.-M. DELORT.Biotransformation of various saccharides and production of exopolymeric substances by cloud-borne Bacillus sp. 3B6. Environmental Science & Technology, 2014, 48, 14238−14247.

Atmospheric microphysics: The nucleation properties of micro-organisms isolated from clouds (ice-nucleation activity, bio-surfactant production) and their impact on the formation and behaviour of clouds (crystal formation, precipitation) are studied.

Droplet-freezing assays (20µL droplets on a cryobath) for investigating the capacity of some microbial strains to catalyze the nucleation of supercooled water into ice crystals.

References:

E. ATTARD, H. YANG, A.-M. DELORT, P. AMATO, U. PÖSCHL, C. GLAUX, T. KOOP, C. MORRIS. Effects of atmospheric conditions on ice nucleation activity of Pseudomonas. Atmospheric Chemistry and Physics, 2012, 12, 10667-10677.

M. JOLY, E. ATTARD, M. SANCELME, L. DEGUILLAUME, C. GUILBAUD, C. E. MORRIS, P. AMATO, A.-M. DELORT Ice nucleation activity of bacteria isolated from cloud water. Atmospheric Environment, 2013, 70, 392-400.

M. JOLY, P. AMATO, L. DEGUILLAUME, M. MONIER, C. HOOSE, A.-M. DELORT Quantification of ice nuclei active at near 0°C temperatures in low-altitude clouds at the Puy de Dôme atmospheric station. Atmospheric Chemistry and Physics, 2014, 14, 8185-8195.

Hanging drop method for measuring the surface tension of biosurfactants produced by microbial strains isolated from clouds

Survival mechanism of micro-organisms from clouds: in order to understand how some microorganisms survive in clouds, the group studies their response to factors encountered in these media (high rates of UV, low temperatures, repeated osmotic stress, freeze-thaw cycles, etc).

Schematic representation of the life cycle of microorganisms in the atmosphere. Microbes are emitted from surfaces (water, soil, vegetation), get airborne and transported upward by turbulent fluxes. They are subject to environmental conditions (indicated in red boxes) in the atmosphere that likely filter for the more resistant of them. In cloud droplets, viable microorganisms can participate to the degradation of organic compounds, and some species can nucleate freezing and, in theory, induce precipitations. They are finally wet deposited and in a position for colonizing new environments. (Scheme extracted from a publication signed by our group in Microbes Magazine in March 2012).

References:

M. JOLY, P. AMATO, M. SANCELME, V. VINATIER, M. ABRANTES, L. DEGUILLAUME, A.-M. DELORT Survival of microbial isolates from clouds toward simulated atmospheric stress factors. Atmospheric Environment, 2015, 117, 92-98.

P. AMATO, M. JOLY, C. SCHAUPP, E. ATTARD, O. MOEHLER, C. E ; MORRIS, Y. BRUNET, A.-M. DELORT Survival and ice nucleation activity of bacteria as aerosol in a cloud simulation chamber. Atmospheric Chemistry and Physics, 2015, 15, 6455-6465.

Integrative biology of clouds: “meta-omics”: The idea is to look directly in situ in cloud waters the functional and structural biodiversity (metagenomics) of microorganisms and the expression of these functions (meta-transcriptomics). The impact of the cloud environment on microbial metabolome is studied by meta-metabolomics.