Microcystis aeruginosa algal blooms in Lake Erie produce the toxin microcystin-LR. Microcystins are hepatotoxins that are attracted to serine/threonine phosphatases, enzymes capable of removing phosphates from proteins during biochemical pathways. Studies indicate that these enzymes are a primary cause of liver and kidney damage that can result in the deaths of livestock and dogs and negative side effects in human, fish, and bird organs. Microcystins are also believed to serve as tumor promoters, substances that increase tumorigenicity. During algal blooms, cyanobacteria release high doses of microcystin-LR. Elevated levels of this toxin are associated with pneumonia, vomiting, abdominal pain, oral blisters, dry coughing, diarrhea, headaches, and sore throats in humans when consumed. In 2014, a Lake Erie algal bloom prompted health officials to warn the Toledo community to avoid coming into contact with tap water due to its high concentration of microcystins. Microcystin poisoning currently has no cure. Our project inserts six enzymes into a bacterium. MlrA breaks the toxic microcystin-LR into linearized microcystin LR. MlrB breaks the linear microcystin LR into a tetrapeptide degradation product, and MlrC then breaks down the tetrapeptide products into smaller peptides and amino acids. MlrD involved with importing the toxins. The purposes of MlrE and MlrF are believed to be imperative to the degradation process. We will insert these enzymes into a ubiquitous species of bacteria found in Lake Erie. This modified bacteria will be able to fully break down microcystin-LR into non-toxic peptides and amino acids. We plan to test the capability of the modified bacteria to break down microcystin-LR in a lab environment before distributing it in Lake Erie, where the bacteria should thrive and continuously break down the toxin. If the modified bacteria is unsuccessful, we plan to modify E. coli to produce these enzymes. The enzymes will go through a purification process before being distributed over algal blooms in Lake Erie.