Glutathione protects microorganisms from uranium exposure

DRESDEN, Germany, June 6 (UPI) -- The cells of microorganisms can withstand uranium exposure when fortified with glutathione. The discovery, made by researchers in Germany, could bolster environmental decontamination efforts.

The heavy metal uranium is a dangerous toxin harmful to human health. It's leached into the environment by mining operations and other industrial processes.

Plants and bacteria are often used to filter toxins from the environment and act as a buffer against the spread of contamination. But a new study at the Helmholtz-Zentrum Dresden-Rossendorf, a German research laboratory, suggests the cells of microorganisms spend so much energy fending off uranium that they are unable to grow or divide.

Cells are freed from their struggle when glutathione is present, the new research confirms. According to the study, published in the journal Applied and Environmental Microbiology, the naturally-occurring antioxidant holds promise as a decontaminating agent.

Researchers were able to monitor the reaction of cells to uranium using a new technique called microcalorimetry, the precise measurement of cellular metabolism.

"We have found out that the metabolism with uranium becomes less efficient," Karim Fahmy, a professor of biochemistry at HZDR, said in a news release. "The cells produce more heat but not more cells. They're virtually running a temperature!"

"Glutathione lowers uranium's chemical toxicity," Fahmy explained. "The cells better withstand the contamination."

Researchers manipulated the genes of Lactococcus lactis, a bacterium used in cheese cultures, to encourage the production of glutathione.

"We thereby have a clean model and do not need to add the glutathione from the outside," Fahmy.

Despite the model, researchers recommend environmental cleanups focus on plants, fungi and bacteria that naturally produce glutathione.