title: Mutants of Citrobacter freundii that transport and utilize melibiose.
abstract: We have isolated mutants of Citrobacter freundii that can grow on melibiose. Inducible alpha-galactosidase activity and melibiose transport activity were detected in the mutant cells but not in the wild-type cells. We detected a DNA region which hybridized with melB (the gene for the melibiose transporter) DNA of Escherichia coli in the chromosomal DNA of wild-type C. freundii. Protons, but not sodium ions, were found to be the coupling cations for melibiose (and methyl-beta-D-thiogalactoside) transport in the mutant cells.
authors.affiliation: Department of Microbiology, Faculty of Pharmaceutical Sciences, Okayama University, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Okazaki
authors.forename: X J
authors.initials: XJ
authors.lastname: Xu
authors.forename: T
authors.initials: T
authors.lastname: Shimamoto
authors.forename: M
authors.initials: M
authors.lastname: Kuroda
authors.forename: T H
authors.initials: TH
authors.lastname: Wilson
authors.forename: T
authors.initials: T
authors.lastname: Tsuchiya
mesh_terms: D001692:Biological Transport; D016971:Citrobacter freundii / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D007700:Kinetics; D008553:Melibiose / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D027981:Symporters; D000519:alpha-Galactosidase / Q000378:metabolism*
chemical_list: D026901:Membrane Transport Proteins; D027981:Symporters; C021548:melibiose permease; D008553:Melibiose; D000519:alpha-Galactosidase