The mrc-1 gene is especially dreaded because it makes bacteria resistant to colistin, the antibiotic of last resort for such infections.
The gene, located on a small fragment of microbial DNA, can move from one bacteria to another across several species, potentially spreading resistance to all antibiotics, which authorities see as a catastrophe scenario.
Scientists have been tracking the gene's movements around the globe since its discovery in humans, poultry and pigs in China in 2015.
Last month, the Centers for Disease Control and Prevention (CDC) announced the establishment of a network of labs that would respond quickly to antibiotic-resistant superbugs in the United States.
It is set to launch work in the fall.