E coli

Escherichia coli

Escherichia coli is one of the world's most widely studied bacteria but it continues to create a massive disease burden, with outbreaks of antibiotic-resistant strains posing an acute public health threat. The scientific community has traditionally used multiple locus sequence typing (MLST) to identify new E. coli strains. But this method can be expensive and time-consuming.

The Weissman lab helped develop an alternative, two-locus typing that is more economical and just as effective as standard, seven-locus typing. This two-locus scheme, known as CH typing, has superior clonal discrimination power and, at the same time, corresponds closely to MLST-based clonal groupings. It is consequently a powerful tool for characterizing the distribution and horizontal movement of genes and plasmids involved in antibiotic resistance, potentially providing valuable assistance to public health officials and infection control practitioners as they identify E. coli strains involved in particular outbreaks.

Learn more about two-locus typing in a 2011 paper in Applied and Environmental Microbiology.