title: Role of leuX in Escherichia coli colonization of the streptomycin-treated mouse large intestine.
abstract: Escherichia coli F-18, a normal human fecal isolate, is an excellent colonizer of the streptomycin-treated mouse large intestine. E. coli F-18 Col-, a derivative of E. coli F-18 that no longer makes the E. coli F-18 colicin, colonizes the mouse large intestine as well as E. coli F-18 when fed alone, but is eliminated when fed together with E. coli F-18. Recently, a random bank of E. coli F-18 DNA was transformed into E. coli F-18 Col-, the resultant population was fed to streptomycin-treated mice, and the intestine was used to select the best colonizer. In this fashion, a 6.5 kb E. coli F-18 DNA fragment was isolated. This fragment was shown to enhance E. coli F-18 Col- mouse large intestinal colonizing ability and survival during stationary phase in intestinal mucus in vitro, as well as stimulate the synthesis of type-1 fimbriae. Here, we present evidence that the gene responsible for the enhanced E. coli F-18 Col- colonizing ability and survival during stationary phase in vitro is leuX. This gene encodes a rare leucine tRNA specific for the UUG codon. In addition, we show that the presence of a functional leuX gene is necessary for E. coli K-12 intestinal colonization and for survival in stationary phase.
authors.affiliation: Department of Biochemistry, Microbiology and Molecular Genetics, University of Rhode Island, Kingston 02881, USA.
authors.forename: J V
authors.initials: JV
authors.lastname: Newman
authors.forename: R
authors.initials: R
authors.lastname: Kolter
authors.forename: D C
authors.initials: DC
authors.lastname: Laux
authors.forename: P S
authors.initials: PS
authors.lastname: Cohen
mesh_terms: D000818:Animals; D002432:Cecum / Q000382:microbiology; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development / Q000472:pathogenicity*; D005798:Genes, Bacterial / Q000235:genetics*; D007420:Intestine, Large / Q000187:drug effects / Q000382:microbiology*; D008297:Male; D051379:Mice; D009093:Mucus / Q000382:microbiology; D012356:RNA, Transfer, Leu / Q000235:genetics*; D013307:Streptomycin / Q000494:pharmacology
chemical_list: D012356:RNA, Transfer, Leu; D013307:Streptomycin