title: Application and Optimization of relE as a Negative Selection Marker for Making Definitive Genetic Constructs in Uropathogenic Escherichia coli.
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.
authors.affiliation: Department 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.
authors.forename: Varnica
authors.initials: V
authors.lastname: Khetrapal
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, NUHS Tower Block, Level 10, Singapore 119074, Singapore. mehershahiks@gis.a-star.edu.sg.
authors.forename: Kurosh S
authors.initials: KS
authors.lastname: Mehershahi
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, NUHS Tower Block, Level 10, Singapore 119074, Singapore. sychen@gis.a-star.edu.sg.
authors.forename: Siyi
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, 1E Kent Ridge Road, NUHS Tower Block, Level 10, Singapore 119074, Singapore. slchen@gis.a-star.edu.sg.|Genome Institute of Singapore, Infectious Diseases Group, 60 Biopolis street, Genome, #02-01, Singapore 138672, Singapore. slchen@gis.a-star.edu.sg.
authors.forename: Swaine L
authors.initials: SL
authors.lastname: Chen
keywords: FimH; UTI89; negative selection