1509022 Wendell, David Source water increasingly contains toxins produced by algal bloom. Easy and effective measurements of the toxins at concentrations that are toxic are not available. The researcher will develop a recombinant cell that will visually indicate if the toxins are present in source water. Successful completion of this project has the potential to reduce hazards associated with algal toxins.
The toxins produced by cyanobacteria affecting human and animal health. The prevalence and toxicity of microcystin drives the need to create a sensor that is both affordable and highly sensitive, with direct applicability to environmental samples. Ribozymes, self-cleaving tertiary aggregates of RNA, have gained applications in gene expression. When RNA aptamers are incorporated into self-cleaving nucleic acid sequences, riboswitches responding solely to a desired ligand can be created. Using this strategy, riboswitch biosensors can be optimized to indicate the presence or absence of the toxin. The long term goal of this research is to produce a riboswitch-mediated biosensor orthogonal to the cyanobacterial toxin microcystin-LR. This bacterial sensor will optically report the presence of the toxin in the form of a simple color change and further assist with microcystin bioremediation by initializing a gene for microcystin-LR degradation (mlrA). The intellectual merit of this project is the design and construction of a riboswitch sensor that endows E. coli with a means of controlling gene expression in response to the presence of microcystin-LR. The central hypothesis is that a microcystin-LR specific riboswitch can predictably indicate the presence of microcystin-LR at very low, physiologically relevant concentrations. The basis for this hypothesis is preliminary results with a compendium of various ribosensor designs and a demonstrated response within the range of the World Health Organization required minimum.The broader impact of this project will be a cyanotoxin biosensor and bioremediation system that can be integrated into current potable water treatment systems and readily deployed in the field. In addition, this project will provide for the support and training of a graduate student, allow for the public presentation of the work at both academic conferences and a local high school, as well as recruitment of 3 underrepresented graduate and undergraduate students to environmental engineering. The 2 undergraduate recruits will be competing in the international synthetic biology competition iGEM, allowing them to build and share their genetically engineered projects with the global iGEM community.
