Bioactive Natural Products in Actinobacteria Isolated in Rainwater From Storm Clouds Transported by Western Winds in Spain

Actinobacteria are the main producers of bioactive natural products essential for human health. Although their diversity in the atmosphere remains largely unexplored, using a multidisciplinary approach, we studied here 27 antibiotic producing Actinobacteria strains, isolated from 13 different precipitation events at three locations in Northern and Southern Spain. Rain samples were collected throughout 2013–2016, from events with prevailing Western winds. NOAA HYSPLIT meteorological analyses were used to estimate the sources and trajectories of the air-mass that caused the rainfall events. Five-day backward air masses trajectories of the diverse events reveals a main oceanic source from the North Atlantic Ocean, and in some events long range transport from the Pacific and the Arctic Oceans; terrestrial sources from continental North America and Western Europe were also estimated. Different strains were isolated depending on the precipitation event and the latitude of the sampling site. Taxonomic identification by 16S rRNA sequencing and phylogenetic analysis revealed these strains to belong to two Actinobacteria genera. Most of the isolates belong to the genus Streptomyces, thus increasing the number of species of this genus isolated from the atmosphere. Furthermore, five strains belonging to the rare Actinobacterial genus Nocardiopsis were isolated in some events. These results reinforce our previous Streptomyces atmospheric dispersion model, which we extend herein to the genus Nocardiopsis. Production of bioactive secondary metabolites was analyzed by LC-UV-MS. Comparative analyses of Streptomyces and Nocardiopsis metabolites with natural product databases led to the identification of multiple, chemically diverse, compounds. Among bioactive natural products identified 55% are antibiotics, both antibacterial and antifungal, and 23% have antitumor or cytotoxic properties; also compounds with antiparasitic, anti-inflammatory, immunosuppressive, antiviral, insecticidal, neuroprotective, anti-arthritic activities were found. Our findings suggest that over time, through samples collected from different precipitation events, and space, in different sampling places, we can have access to a great diversity of Actinobacteria producing an extraordinary reservoir of bioactive natural products, from remote and very distant origins, thus highlighting the atmosphere as a contrasted source for the discovery of novel compounds of relevance in medicine and biotechnology.

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The Extreme Precipitation Index (EPI): A Coupled Dynamic–Thermodynamic Metric to Diagnose Midlatitude Floods Associated with Flow Reversal

Weather and Forecasting ◽

10.1175/waf-d-18-0156.1 ◽

2019 ◽

Vol 34 (5) ◽

pp. 1257-1276 ◽

Cited By ~ 1

Author(s):

Shawn M. Milrad ◽

Eyad H. Atallah ◽

John R. Gyakum ◽

Rachael N. Isphording ◽

Jonathon Klepatzki

Keyword(s):

Extreme Precipitation ◽

Western Europe ◽

Potential Temperature ◽

Precipitation Index ◽

Flow Reversal ◽

Precipitation Event ◽

Day Range ◽

Extreme Precipitation Events ◽

Extreme Precipitation Index ◽

Precipitation Events

Abstract The extreme precipitation index (EPI) is a coupled dynamic–thermodynamic metric that can diagnose extreme precipitation events associated with flow reversal in the mid- to upper troposphere (e.g., Rex and omega blocks, cutoff cyclones, Rossby wave breaks). Recent billion dollar (U.S. dollars) floods across the Northern Hemisphere midlatitudes were associated with flow reversal, as long-duration ascent (dynamics) occurred in the presence of anomalously warm and moist air (thermodynamics). The EPI can detect this potent combination of ingredients and offers advantages over model precipitation forecasts because it relies on mass fields instead of parameterizations. The EPI’s dynamics component incorporates modified versions of two accepted blocking criteria, designed to detect flow reversal during the relatively short duration of extreme precipitation events. The thermodynamic component utilizes standardized anomalies of equivalent potential temperature. Proof-of-concept is demonstrated using four high-impact floods: the 2013 Alberta Flood, Canada’s second costliest natural disaster on record; the 2016 western Europe Flood, which caused the worst flooding in France in a century; the 2000 southern Alpine event responsible for major flooding in Switzerland; and the catastrophic August 2016 Louisiana Flood. EPI frequency maxima are located across the North Atlantic and North Pacific mid- and high latitudes, including near the climatological subtropical jet stream, while secondary maxima are located near the Rockies and Alps. EPI accuracy is briefly assessed using pattern correlation and qualitative associations with an extreme precipitation event climatology. Results show that the EPI may provide potential benefits to flood forecasters, particularly in the 3–10-day range.

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The influence of 14CO2 releases from regional nuclear facilities at the Heidelberg 14CO2 sampling site (1986–2014)

10.5194/acp-2018-84 ◽

2018 ◽

Author(s):

Matthias Kuderer ◽

Samuel Hammer ◽

Ingeborg Levin

Keyword(s):

Dispersion Model ◽

Correction Term ◽

Sampling Site ◽

Atmospheric Dispersion ◽

Mean Value ◽

Anthropogenic Sources ◽

Monitoring Site ◽

Nuclear Facilities ◽

Wind Fields ◽

Mean Values

Abstract. Atmospheric Δ14CO2 measurements are a well established tool to estimate regional fossil fuel-derived CO2 fluxes. However, emissions from nuclear facilities can significantly alter the regional Δ14CO2 level. In order to accurately quantify the 14CO2 signal, a correction term for anthropogenic sources has to be determined. In this study, the HYSPLIT atmospheric dispersion model has been applied to calculate the correction term for the long-term 14CO2 monitoring site in Heidelberg. Wind fields with a spatial resolution of 2.5° × 2.5°, 1° × 1° and 0.5° × 0.5° show systematic deviations, with coarser resolved wind fields leading to higher mean values for the correction. The mean correction for the period from 1986–2014, if based on the 0.5° × 0.5° wind field, which we assume as the most accurate, is 2.3 ‰ with a standard deviation of 2.1 ‰ and maximum values up to 15.2 ‰. After ceasing operations at the most important 14CO2 source near Heidelberg in 2011, monthly nuclear correction terms decreased to less than 2 ‰, with a mean value of (0.44 ± 0.32) ‰ from 2012 to 2014.

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The Controls of Iron and Oxygen on Hydroxyl Radical (•OH) Production in Soils

Soil Systems ◽

10.3390/soilsystems3010001 ◽

2018 ◽

Vol 3 (1) ◽

pp. 1 ◽

Cited By ~ 6

Author(s):

Adrianna Trusiak ◽

Lija Treibergs ◽

George Kling ◽

Rose Cory

Keyword(s):

Hydroxyl Radical ◽

The Arctic ◽

Co2 Production ◽

Precipitation Event ◽

Arctic Soils ◽

Production And Consumption ◽

Simulated Precipitation ◽

O2 Supply ◽

Carbon Dioxide Co2 ◽

Precipitation Events

Hydroxyl radical (•OH) is produced in soils from oxidation of reduced iron (Fe(II)) by dissolved oxygen (O2) and can oxidize dissolved organic carbon (DOC) to carbon dioxide (CO2). Understanding the role of •OH on CO2 production in soils requires knowing whether Fe(II) production or O2 supply to soils limits •OH production. To test the relative importance of Fe(II) production versus O2 supply, we measured changes in Fe(II) and O2 and in situ •OH production during simulated precipitation events and during common, waterlogged conditions in mesocosms from two landscape ages and the two dominant vegetation types of the Arctic. The balance of Fe(II) production and consumption controlled •OH production during precipitation events that supplied O2 to the soils. During static, waterlogged conditions, •OH production was controlled by O2 supply because Fe(II) production was higher than its consumption (oxidation) by O2. An average precipitation event (4 mm) resulted in 200 µmol •OH m−2 per day produced compared to 60 µmol •OH m−2 per day produced during waterlogged conditions. These findings suggest that the oxidation of DOC to CO2 by •OH in arctic soils, a process potentially as important as microbial respiration of DOC in arctic surface waters, will depend on the patterns and amounts of rainfall that oxygenate the soil.

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The influence of 14CO2 releases from regional nuclear facilities at the Heidelberg 14CO2 sampling site (1986–2014)

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-7951-2018 ◽

2018 ◽

Vol 18 (11) ◽

pp. 7951-7959 ◽

Cited By ~ 3

Author(s):

Matthias Kuderer ◽

Samuel Hammer ◽

Ingeborg Levin

Keyword(s):

Wind Field ◽

Dispersion Model ◽

Correction Term ◽

Sampling Site ◽

Atmospheric Dispersion ◽

Mean Value ◽

Monitoring Site ◽

Nuclear Facilities ◽

Wind Fields ◽

Mean Values

Abstract. Atmospheric Δ14CO2 measurements are a well-established tool to estimate the regional fossil-fuel-derived CO2 component. However, emissions from nuclear facilities can significantly alter the regional Δ14CO2 level. In order to accurately quantify the signal originating from fossil CO2 emissions, a correction term for anthropogenic 14CO2 sources has to be determined. In this study, the HYSPLIT atmospheric dispersion model has been applied to calculate this correction for the long-term Δ14CO2 monitoring site in Heidelberg. Wind fields with a spatial resolution of 2.5∘ × 2.5∘, 1∘ × 1∘, and 0.5∘ × 0.5∘ show systematic deviations, with coarser resolved wind fields leading to higher mean values for the correction. The finally applied mean Δ14CO2 correction for the period from 1986–2014 is 2.3 ‰ with a standard deviation of 2.1 ‰ and maximum values up to 15.2 ‰. These results are based on the 0.5∘ × 0.5∘ wind field simulations in years when these fields were available (2009, 2011–2014), and for the other years they are based on 2.5∘ × 2.5∘ wind field simulations, corrected with a factor of 0.43. After operations at the Philippsburg boiling water reactor ceased in 2011, the monthly nuclear correction terms decreased to less than 2 ‰, with a mean value of 0.44 ± 0.32 ‰ from 2012 to 2014.

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