BIOTAC aimed at study the mechanisms operating with flagellated bacteria for bioavailability enhancements and, therefore, a faster turnover of HOCs in soils. We studied, at the microorganism scale, the role of bacterial taxis in chemical gradients (chemotaxis) in pollutant bioavailability, modelling and integrating them with other microbial adaptations (i. e. the production of biosurfactants). We have developed strategies to improve bacterial transport to pollutant sources, using carefully selected biological and chemical effectors (respectively including, mycelial networks and organic compounds), that favour flagella-mediated taxis, and the comobilization of immotile degrading strains. All this knowledge, was applied in controlled soil bioremediation experiments, in order to study the enhancement of HOCs’ degradation.
The tasks performed during this fellowship were ascribed to eight specific work packages (WP), five of which were related to purely scientific tasks, and the last three to dissemination, training and project management activities. The main results achieved are summarized in the next bullet points:
-WP1. Bacterial taxis as the driver for enhancing pollutant bioavailability and biodegradability: Characterization and quantification of chemotactic motility parameters of Pseudomonas putida G7 in bulk and porous media (including microfluidic devices) and development of a mathematical model of bacterial dispersion in micropores (in collaboration with AgroParisTech, France).
-WP2. Role of “fungal highways” in the motility and degradation efficiency of flagellated bacterial strains: Study of the effect of fungal highways on the dispersion of chemotactic bacteria and immotile bacteria in engineered porous systems (including microfluidic devices). Activities developed during the secondment in UFZ (Germany).
-WP3. Enhancement of bacterial dispersal using chemoeffectors: Characterization of chemotactic motility inside pores (including microfluidic devices).
-WP4. Synergies with other bioavailability-enhancing and catabolic mechanisms: Characterization and optimization of biosurfactant production of Bacillus subtilis DSM10, applied in WP5, together with P. putida G7.
-WP5. Assessing the risks and benefits from flagellated bacteria and pollutant bioavailability enhancements in mesocosms with field-contaminated soils: Greenhouse bioremediation experiments of kerosene-contaminated soils, using B. subtilis DSM10 as a biosurfactant producer and P. putida G7 as a co-mobilizer agent to enhance kerosene bioavailability.
Scientific papers, and communications to conferences and workshops, as well as knowledge transfer activities, assured the exploitation and dissemination of the results, and their accessibility for further research activities related to BIOTAC. Results have also been disseminated through BIOTAC twitter account (@BIOTAC_MSC), Dr. Balseiro-Romero twitter (@m_balseiro) and ResearchGate (
https://www.researchgate.net/profile/Maria-Balseiro-Romero(se abrirá en una nueva ventana)) accounts, and outreach activities of IRNAS-CSIC (
https://www.irnas.csic.es/en/(se abrirá en una nueva ventana)).
