DATE: Friday, November 09, 2018 TIME: 2:30 pm (refreshments at 2:15 pm) PLACE: ENR building, room 223 14 College Farm Road, New Brunswick, NJ
Mengyan "Ian" Li
Department of Chemistry and Environmental Science, NJIT
Application of Molecular Tools to Bioremediation of 1,4-Dioxane
1,4-Dioxane (dioxane) contamination has emerged as a compelling global water concern given its carcinogenic potential and prevalent occurrence in aquatic environments. Recent national water quality surveys revealed detection of dioxane was among the top frequency and exceedance above its health-based limit (i.e., 0.35 µ/L) in the U.S., posing immense exposure risks to human and wildlife animals. In situ biological treatments, including Monitored Natural Attenuation (MNA) and Bioremediation, exist as environment-benign and cost-efficient options to manage the large and diluted plumes that are commonly formed by dioxane. However, field application of bioremediation for dioxane cleanup is hindered due to our limited knowledge of the biodegradation mechanisms (e.g., genes, enzymes, and pathways), as well as the lack of the capability to sustainably enhance and unequivocally monitor the onsite biological activities.
This presentation is aimed to provide a timely scientific update by integrating our most recent research findings to shed light on overcoming the technological hurdles for MNA and bioremediation of dioxane. Briefly, a novel multi-component monooxygenase was identified and characterized in a dioxane metabolizer given its capability of initiating the cleavage of dioxane and other cyclic ethers. The discovery of this catabolic gene advances our fundamental understanding of dioxane metabolic pathways and enables development of molecular tools to assess bioremediation potential at contaminated sites. Further, combination of conventional isolation and fluorescence-activated cell sorting approaches enables the identification of new dioxane degraders with superior degradation capabilities from the environmental samples or enriched consortia. Overall, state-of-the-art molecular techniques are of significant application value to unearth and assess the performance of natural attenuation and bioremediation of dioxane plumes, which thus provides a rigorous basis for regulatory agencies and decision makers to select or reject these cost-efficient biological remediation techniques for site cleanup.