Transgenic Escherichia coli Efficiently Captures Cobalt and Nickel Ions in Water Solutions

Metal contamination is widespread and there is a growing need to detoxify polluted ecosystems. Industrial wastewater, surface water and ground water all need to be cleansed to lessen soil contamination. Bacteria, which contain metal transporters, can provide a potential alternative to water detoxification.

Corinne Dorel of France's Universite de Lyon, and her team evaluated the ability of bacteria as biofilters for capturing nickel and cobalt ions in water solutions. Using genetic modification, the system preventing the build up of cobalt and nickel in the E. coli, Rcn, was disabled, thus increasing its metal uptake. NiCoT, an improved metallic transporter from Novosphingobium aromaticivorans, was also inserted into E. coli.

The modified strain showed enhanced nickel and cobalt ion uptake, with a maximum metal ion accumulation of 6 mg/g of bacteria dry weight in 10 minutes. This demonstrates the efficient use of genetic engineering to increase metal capture by E. coli. Biofiltration of nickel and cobalt by bacteria is promising for treating contaminants at an industrial scale.

Learn more on this new biofiltration method by visiting: http://www.jbioleng.org/content/pdf/1754-1611-8-19.pdf.