Sunday, 25 February 2018

Tracing the evolution of E. coli

A team from the University of Delaware and University of California, San Diego recently uncovered new insights about how E. coli bacteria mutate in response to a life-threatening challenge.

To do this, the team brought together two experimental methods that aren't typically used in tandem: whole-genome sequencing and metabolic flux analysis.

At UC-San Diego, Adam Feist, an associate project scientist in bioengineering, and Bernhard Palsson, the Galletti Professor of Bioengineering, modified and then evolved ten strains of E. coli bacteria. They knocked out the bacterial cells' ability to utilize phosphoglucose isomerase, an enzyme that plays a critical role in the metabolism of glucose, a sugar. Robbing E. coli cells of the phosphoglucose isomerase enzyme is akin to starving them, stunting their growth by 80 percent.

However, as these E. coli cells evolved and multiplied, they eventually recovered between 46 and 71 percent of their growth rate.

The research team then used genomic analysis and flux analysis to figure out how the cells mutated and adapted to recover.


Christopher P. Long, Jacqueline E. Gonzalez, Adam M. Feist, Bernhard O. Palsson, Maciek R. Antoniewicz. Dissecting the genetic and metabolic mechanisms of adaptation to the knockout of a major metabolic enzyme inEscherichia coli. Proceedings of the National Academy of Sciences, 2018; 115 (1): 222 DOI: 10.1073/pnas.1716056115

Posted by Dr. Tim Sandle

Special offers