The main objective of this project is to study and understand the behaviour and the mechanisms behind TBT resistance by marine estuarine bacteria. The approach will include the isolation of culturable marine bacterial isolates that will allow for the detection and isolation of the genes involved in TBT resistance. Additionally bacterial communities will also be studied as they constitute the base of aquatic food webs and are responsible for the bulk of organic matter transformations and mineral recycling in aquatic environments. Also, due to the various sensitivities of different microorganisms to toxic chemicals and the dominance of highly diverse microbes in natural environments and, bacterial community responses to the toxic effect of TBT will also be analyzed. Specific objectives are related and constitute specific work tasks: i) Isolation, identification and characterization of TBT resistant/tolerant culturable bacteria A from where a collection of TBT resistant/tolerant bacteria will be selected for further studies ii) Microbial community-level toxicity testing where community-level toxicity testing of chemicals should supplement single-species laboratory assays when testing potential harmful chemicals like TBTs, iii) Characterization of bacterial abundance, viability, activity and functional diversity designed to compare bacterial density, viability, activity and functional diversity of bacterial communities in coastal waters in order to evaluate the effect of TBT on bacterial metabolism, iv) TBT degradation assay to demonstrate the mechanism behind TBT resistance/tolerance by marine bacteria and v) Isolation and characterization of the genes involved in TBT resistance. It is well known that isolation and culturing techniques miss out a large part of the bacterial community. Therefore the use of molecular techniques will enable us to select interesting organisms for a future construction of microbial consortia with TBT degrading capabilities. The proposed study will allow for the isolation of the encoded TBT resistance genes in marine bacteria that is of extreme importance for future research
