Engineered Bacteria Degrades Five Organic Pollutants

Chinese scientists have announced the engineering of a novel bacterial strain that can simultaneously degrade five different types of organic pollutants found in high-salinity industrial wastewater . The findings, which represent a significant advance in synthetic biology, were published online in the prestigious journal Nature .

The discovery is the result of the collaboration of a joint research team from the Shenzhen Institutes of Advanced Technology (SIAT) of the Chinese Academy of Sciences and the Shanghai Jiao Tong University.

Highly salinity industrial wastewater, typically discharged from chemical plants and oil and gas extraction sites, contains a complex mixture of contaminants, including suspended solids, organic compounds, heavy metals, toxic chemicals, and nutrient salts .

Although there are microorganisms in nature that are capable of individually degrading some of these pollutants , their efficiency is often limited , as each strain tends to target one or two specific contaminants. When faced with complex mixtures of pollutants such as oil, heavy metals or radioactive substances, natural microorganisms are often ineffective.

To overcome this limitation, the research team used synthetic biology techniques to engineer a bacterial strain with modular metabolic pathways . By integrating five artificial degradation pathways into a single bacterium, the researchers enabled the simultaneous breakdown of biphenyl, phenol, naphthalene, dibenzofuran, and toluene, representative compounds of aromatic pollutants .

Experimental validation demonstrated the remarkable efficiency of the engineered strain: within 48 hours, the bacterium achieved greater than 60 percent removal of all five target pollutants, with complete degradation of biphenyl and degradation rates approaching 90 percent for complex compounds such as toluene and dibenzofuran .

This engineered bacterium holds significant potential for several environmental applications, including oil spill cleanup, remediation of contaminated industrial sites, and even biodegradation of microplastics , said Dai Junbiao, one of the corresponding authors of the study and a visiting researcher at SIAT.

Cover image generated with the support of Gemini