20971911
not annotated - annotated - LINNAEUS only
Glucose-dependent activation of Bacillus anthracis toxin gene expression and virulence requires the carbon catabolite protein CcpA.
Sensing environmental conditions is an essential aspect of bacterial physiology and virulence. In Bacillus anthracis, the causative agent of anthrax, transcription of the two major virulence factors, toxin and capsule, is triggered by bicarbonate, a major compound in the mammalian body. Here it is shown that glucose is an additional signaling molecule recognized by B. anthracis for toxin synthesis. The presence of glucose increased the expression of the protective antigen toxin component-encoding gene (pagA) by stimulating induction of transcription of the AtxA virulence transcription factor. Induction of atxA transcription by glucose required the carbon catabolite protein CcpA via an indirect mechanism. CcpA did not bind specifically to any region of the extended atxA promoter. The virulence of a B. anthracis strain from which the ccpA gene was deleted was significantly attenuated in a mouse model of infection. The data demonstrated that glucose is an important host environment-derived signaling molecule and that CcpA is a molecular link between environmental sensing and B. anthracis pathogenesis.
Ann file
T1 Species 32 50 Bacillus anthracis
N1 Reference T1 Taxonomy:1392
T2 Species 232 250 Bacillus anthracis
N2 Reference T2 Taxonomy:1392
T3 Species 275 282 anthrax
N3 Reference T3 Taxonomy:1392
T4 Species 502 514 B. anthracis
N4 Reference T4 Taxonomy:1392
T5 Species 943 962 B. anthracis strain
N5 Reference T5 Taxonomy:1392
T6 Species 1034 1039 mouse
N6 Reference T6 Taxonomy:10090
T7 Species 1223 1235 B. anthracis
N7 Reference T7 Taxonomy:1392
#1 AnnotatorNotes T3 TODO check