Structural and functional diversity of microbial communities from a lake sediment contaminated with trenbolone, an endocrine-disrupting chemical

Effects of trenbolone (TBOH), a hormone used in cattle production, on the structure and function of microbial communities in a fresh water sediment from a lake in Southern Germany were studied in a microcosm experiment. The microbial community structure and the total gene pool of the sediment, assessed by 16S rRNA/rDNA and RAPD fingerprint analysis, respectively, were not significantly affected by TBOH. In contrast, the N-acetyl-glucosaminidase activity was almost 50% lower in TBOH treated samples (P<0.05). Also, the substrate utilization potential, measured using the BIOLOG system, was reduced after TBOH treatment. Interestingly, this potential did not recover at the end of the experiment, i.e. 19 days after the addition of the chemical. Repeated application of TBOH did not lead to an additional reduction in the substrate utilization potential. Overall results indicate that microbial community function was more sensitive to TBOH treatment than the community structure and the total gene pool.