Dynamics ofHeterocapsasp. and the associated attached and free-living bacteria under the influence of dispersed and undispersed crude oil
| Autor: | Atsushi Sato, Tatiana Severin, Hernando P. Bacosa, Deana L. Erdner |
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| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
Bacteria biology fungi 030106 microbiology Dinoflagellate Heterocapsa sp biology.organism_classification Crude oil Applied Microbiology and Biotechnology Dispersant 03 medical and health sciences Petroleum 030104 developmental biology Phytoplankton Botany Dinoflagellida Food science Corexit Water Pollutants Chemical Oil toxicity |
| Zdroj: | Letters in Applied Microbiology. 63:419-425 |
| ISSN: | 0266-8254 |
| Popis: | While many studies have examined the impact of oil on phytoplankton or bacteria, very few considered the effects on the biological complex formed by phytoplankton and their associated phytoplankton-attached (PA) and free-living (FL) bacteria. However, associated bacteria can affect the physiology of phytoplankton and influence their stress responses. In this study, we monitored the growth of Heterocapsa sp., an armoured dinoflagellate, exposed to crude oil, Corexit dispersant, or both. Growth of Heterocapsa sp. is unaffected by crude oil up to 25 ppm, a concentration similar to the lower range measured on Florida beaches after the Deepwater Horizon oil spill. The PA bacteria community was resistant to exposure, whereas the FL community shifted towards oil degraders; both responses could contribute to Heterocapsa sp. oil resistance. The growth rate of Heterocapsa sp. decreased significantly only when exposed to dispersed oil at 25 ppm, indicating a synergistic effect of dispersant on oil toxicity in this organism. For the first time, we demonstrated the decoupling of the responses of the PA and FL bacteria communities after exposure to an environmental stress, in this case oil and dispersant. Our findings suggest new directions to explore in the understanding of interactions between unicellular eukaryotes and prokaryotes.In the environment, oil spills have the capacity to modify phytoplankton communities, with important consequences on the food web and the carbon cycle. We are just beginning to understand the oil resistance of phytoplankton species, making it difficult to predict community response. In this study we highlighted the strong resistance of Heterocapsa sp. to oil, which could be associated with its resilient attached bacteria and oil degradation by the free-living bacteria. This finding suggests new directions to explore in the understanding of oil impacts and interactions between eukaryotic and prokaryotic microbes. |
| Databáze: | OpenAIRE |
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