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Updated: Mar 26, 2026

Mapping Bacterial Functional Networks and Pathways in Escherichia Coli using Synthetic Genetic Arrays
Published on: November 12, 2012
Application and Optimization of relE as a Negative Selection Marker for Making Definitive Genetic Constructs in
Varnica Khetrapal1, Kurosh S Mehershahi2, Siyi Chen3
1Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, NUHS Tower Block, Level 10, Singapore 119074, Singapore. khetrapalv@gis.a-star.edu.sg.
Abstract:
Studies of Uropathogenic Escherichia coli (UPEC) pathogenesis have relied heavily on genetic manipulation to understand virulence factors. We applied a recently reported positive-negative selection system to create a series of unmarked, scarless FimH mutants that show identical phenotypes to previously reported marked FimH mutants; these are now improved versions useful for definitive assignment of phenotypes to FimH mutations. We also increased the efficiency of this system by designing new primer sites, which should further improve the efficiency and convenience of using negative selection in UTI89, other UPEC, and other Enterobacteriaceae.

