Using biological metaldehyde degradation for bioremediation and diagnostics

Lead Research Organisation: University of York
Department Name: Biology

Abstract

Metaldehyde is a molluscicide used to kill slugs, thus protecting economically important crops, particularly potatoes, wheat and oil-seed rape. Following its use, metaldehyde runs off agricultural land and can accumulate in river and reservoir water, ultimately contaminating drinking water where it is recalcitrant to degradation. An EU defined maximum concentration in drinking water for this compound of 0.1 g/L has to be achieved, yet as currently operated metaldehyde passes through most water treatment works relatively untouched. Control of metaldehyde contamination is a priority issue for Water Companies in the UK (metaldehyde was responsible for 232/253 failures in water quality tests in England in 2012). There is currently no cost effective and reliable process for metaldehyde degradation. The difficult situation is exacerbated by a reliance on laborious laboratory-based chromatographic procedures required for metaldehyde measurement.
This NERC-funded CASE studentship aims to rectify this problem by developing the application of naturally occurring microbiological degradation as a new solution for metaldehyde contamination. In a second strand of the project, we will exploit biological metaldehyde degradation mechanisms to design metaldehyde biosensors, thus leading to the creation of a new approach for field-testing of metaldehyde. A student with a background in microbiology, biotechnology and/or biochemistry who is prepared to work in an interdisciplinary way will be well equipped to take on this project, which will build upon earlier findings at York with respect to biological degradation of metaldehyde. Major objectives of the project are to: (i) improve existing bacterial isolates that can degrade metaldehyde to improve their properties for drinking water treatment, (ii) characterise the enzyme system for metaldehyde degradation to inform strain improvement and develop of sensor technology, (iii) develop electronic and optical methods for metaldehyde detection using biological components as biosensors.
This project is a collaboration between the University of York (led by Dr. James Moir in the Department of Biology, with Dr. Steven Johnson, Department of Electronics as a co-supervisor) and Thames Water and the Food and Environment Research Agency (FERA Science Limited). The project will involve work at the University of York, at FERA (situated just outside York) and a significant industrial placement with Thames Water (using their water treatment research facilities in London).

Publications

10 25 50
 
Description Previous research has identified and isolated microorganisms which are capable of degrading metaldehyde however the mechanism by which is occurs and the enzyme(s) responsible were unknown. In my research project, I have identified, confirmed and purified the enzyme responsible for metaldehyde degradation.
Exploitation Route The enzyme has great potential for industrial purposes. By mass producing the enzyme, metaldehyde can be specifically removed from the water supply this could therefore help ease the burden on the water companies who are frequently going over the pesticide limit of 0.01ug/L. Further investigations could see optimisation of the enzyme through site directed mutagenesis as well as methods to improve stability.
Sectors Chemicals,Environment,Pharmaceuticals and Medical Biotechnology

URL http://N.A