Development of a marine compatible biological assay for mutagenic compounds

One of the primary negative effects of environmental oil exposure is the potential for mutagenic, or DNA damaging effects. This can lead to heritable genetic damage in higher organisms with long-term environmental impact. The biological effect of contamination is difficult to estimate on the basis of chemical profiles due to the complexity of environmental samples. Thus, biologically based assays give a closer approximation of the actual ecological impacts of contamination. To measure the mutagenic or DNA damaging potential of samples we currently utilize the Microscreen Assay, which is based upon a strain of Escherichia coli that is sensitive to mutagenic compounds in a dose-specific way. However, this strain is not optimized for marine samples because E. coli is adapted for growth in freshwater environments. As a consequence the detection limit with this assay is fairly high allowing the possibility of false negative results. We developed an analogous assay utilizing a cultured marine strain. We screened marine bacterial isolates and marine viruses to develop a marine bacterial strain that is sensitive to mutagenic contaminants in a dose specific manner that will increase the sensitivity and decrease the detection threshold for mutagenic contaminants in marine environments.