The chimeric VirA-tar receptor protein is locked into a highly responsive state.
The wild-type VirA protein is known to be responsive not only to phenolic compounds but also to sugars via the ChvE protein (G. A. Cangelosi, R. G. Ankenbauer, and E. W. Nester, Proc. Natl. Acad. Sci. USA 87:6708-6712, 1990, and N. Shimoda, A. Toyoda-Yamamoto, J. Nagamine, S. Usami, M. Katayama, Y. Sakagami, and Y. Machida, Proc. Natl. Acad. Sci. USA 87:6684-6688, 1990). It is shown here that the mutant VirA(Ser-44, Arg-45) protein and the chimeric VirA-Tar protein are no longer responsive to sugars and the ChvE protein. However, whereas the chimeric VirA-Tar protein was found to be locked in a highly responsive state, the VirA(Ser-44, Arg-45) mutant protein appeared to be locked in a low responsive state. This difference turned out to be important for tumorigenicity of the host strains in virulence assays on Kalanchoë daigremontiana.
Turk
S C
SC
Clusius Laboratory, Leiden University, The Netherlands.
van Lange
R P
RP
Sonneveld
E
E
Hooykaas
P J
PJ
D016960:Agrobacterium tumefaciens / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D002628:Chemoreceptor Cells; D003001:Cloning, Molecular; D029968:Escherichia coli Proteins; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D010944:Plants / Q000382:microbiology; D011956:Receptors, Cell Surface; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D015183:Restriction Mapping; D037521:Virulence Factors
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D011956:Receptors, Cell Surface; D011993:Recombinant Fusion Proteins; C057331:Tar protein, E coli; D037521:Virulence Factors