INVESTIGADORES
DELGADO Monica Alejandra
congresos y reuniones científicas
Título:
The phosphorelay mechanism of the RcsC/YojN/RcsB system in Salmonella enterica
Autor/es:
MARÍA DE LAS MERCEDES PESCARETTI; ROBERTO MORERO; MÓNICA A. DELGADO
Lugar:
Mar del Plata-Buenos Aires (Argentina)
Reunión:
Congreso; XLIII Annual Meeting of the Argentine Society for Biochemistry and Molecular Biology; 2007
Institución organizadora:
Argentine Society for Biochemistry and Molecular Biology
Resumen:
The Rcs phosphorelay system involves the sensor protein RcsC, the cognate response regulator RcsB, and the histidin-containing phosphotransfer protein YojN, which serve as an intermediary in the phosphoryl transfer from RcsC to RcsB.  Previously we found that the overproduction of RcsB regulator promotes the Rcs system activation, in the rcsC or yojN mutants, but not in the double mutant yojN rcsC. These results suggested that only RcsB-P, the RcsB active form, is able to induce the RcsB-dependent genes modulation, like cps and flhDC. We are interested to define the Rcs phosphorelay transduction mechanism. To determinate if RcsC or YojN can independently transfer the phosphate group to RcsB, or if in this process is necessary that both protein act together, is necessary to purify all the Rcs system components, which will be used in an in vitro phosphorylation assays. Therefore, we cloned the rcsB, rcsC and yojN genes using the pUHE-21 vector. To facilitate the protein purification procedure, we added in the N-terminal region a sequence that codify for the His-Tag. In these assay we observed that RcsC and YojN proteins appear in the insoluble fraction. In order to overcome this problem we resolved to use the pET41.3 system, which facilitate the generation of a fusion with the nusA gene to increment the solubility of our interest proteins.