title: AtxA activates the transcription of genes harbored by both Bacillus anthracis virulence plasmids.
abstract: Fully virulent Bacillus anthracis bacilli are encapsulated and toxinogenic. These bacteria carry two plasmids, pXO1, and pXO2, encoding toxins and capsule synthetic-enzymes (capB, C, A, dep), respectively. The PXO1 plasmid strongly enhances capsule formation. This influence was studied by analysing the expression of a capB-lacZ fusion in various backgrounds. The beta-galactosidase activities were similar in a delta atxA strain and a pXO1 cured strain. Moreover, the capB-lacZ expression level could be restored, in a pXO1 cured strain, by addition of atxA in trans. Thus, we conclude that the pX01 influence on capsule synthesis is mediated by AtxA, the pXO1-encoded trans-activator of the toxin gene expression.
authors.affiliation: Laboratorie de Génétique Moléculaire des Toxines (URA 1858, CNRS), Institut Pasteur, Paris, France.
authors.forename: J
authors.initials: J
authors.lastname: Guignot
authors.forename: M
authors.initials: M
authors.lastname: Mock
authors.forename: A
authors.initials: A
authors.lastname: Fouet
mesh_terms: D001408:Bacillus anthracis / Q000235:genetics* / Q000472:pathogenicity; D016667:Bacterial Capsules / Q000235:genetics / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D018698:Glutamic Acid / Q000235:genetics; D007763:Lac Operon; D009693:Nucleic Acid Hybridization; D010957:Plasmids / Q000235:genetics*; D011995:Recombination, Genetic; D017384:Sequence Deletion; D015534:Trans-Activators / Q000235:genetics* / Q000502:physiology*; D015533:Transcriptional Activation; D014161:Transduction, Genetic; D014169:Transformation, Bacterial; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D004269:DNA, Bacterial; D015534:Trans-Activators; D018698:Glutamic Acid; D001616:beta-Galactosidase