title: Genetic basis for conversion of rough-to-smooth colony morphology in Actinobacillus actinomycetemcomitans.
abstract: The basis of the rough-to-smooth conversion of Actinobacillus actinomycetemcomitans was examined. Smooth variants often contained mutations at the flp promoter region. Replacing the mutated flp promoter with the wild-type promoter restored the rough phenotype. The expression level of the flp promoter was approximately 100-fold lower in smooth than in rough strains. Mutations of the flp promoter are a cause of the rough-to-smooth conversion.
authors.affiliation: Division of Primary Oral Health Care, University of Southern California School of Dentistry, 925 W. 34th Street, Los Angeles, CA 90089-0641, USA.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Amy
authors.initials: A
authors.lastname: Liu
authors.forename: Casey
authors.initials: C
authors.lastname: Chen
mesh_terms: D016976:Aggregatibacter actinomycetemcomitans / Q000166:cytology* / Q000235:genetics* / Q000648:ultrastructure; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D046529:Microscopy, Electron, Transmission; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic
chemical_list: D001426:Bacterial Proteins; C113731:Flp protein, bacteria