"L-serine, this particular amino acid that we used, [...] we can build it in our bodies, ourselves," researcher Max Riekeles, who is helping to develop the alien-hunting device, told Mashable.

One of the chemicals the bacteria seemed particularly drawn to was serine, an amino acid found in human blood that is also a common ingredient in protein drinks. The research finding, published in ...

How do enzymes cause tremendous increases in reaction rates? Learn how a group of enzymes called the serine proteases work.