All that glitters is not gold, and the shine of most modern gold deposits are hidden underneath layers of dirt, soil and sand. Finding these deposits usually requires expensive and time-consuming chemical analysis of soil samples. Recently, an international team of reseachers met this challenge of gold exploration and prospecting by turning a common gut microbe, Escherichia coli (E. coli), into a miniature gold detection device.
In a recent paper published in PLoS One, researchers from the University of Nebraska and their collaborators in Australia detail how they have genetically modified E. coli to act as a gold biosensor by borrowing the golTSB genes from a closely related microbe, Salmonella typhimurium. By pairing these gold recognition genes to a known enzymatic activity, researchers can detect and quantify small amounts of gold by simply measuring a change in the color of the bacteria-containing solution. The gold detection limit for this biosensor is on par with that of the chemical analysis currently used in the industry, which is slower and involves much more expensive instruments.
These proof-of-concept studies, which were partly funded by both Newmont Exploration Proprietary Limited and Barrick Gold of Australia Limited, are the latest step towards the development of a quick, accurate and specific biosensor that will make examining potential gold mining sites easier and faster. The authors of the study demonstrate that their biosensor can be used to determine the concentration of gold in a soil sample or a sample containing multiple metals. This is an improvement over earlier research of prototype biosensors, which only demonstrated detection in relatively pure samples.
For more detail and commentary about this study, please select 'Read More'. Do you think cell based biosensors will revolutionize gold exploration? Comments are welcome below!