INVESTIGADORES
NOTO LLANA Mariangeles
congresos y reuniones científicas
Título:
Impaired expression and secretion of SOPB, SOPD and SOPE2 in Salmonella DAM mutants
Autor/es:
GIACOMODONATO MN; GARTNER, A; GARCIA BLATZ, M; SARNACKI SH; NOTO LLANA M; CERQUETTI MC
Reunión:
Congreso; XLVII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2011
Resumen:
Dam methylation is an essential factor involved in the virulence of
an increasing number of bacterial pathogens including Salmonella
spp. dam mutants have a reduced capacity to colonize murine organs
compared to the parental strain. This partial inability could be
related to a reduced secretion of invasion proteins. Then, we
investigated the involvement of Dam methylation on the expression
and secretion of essential proteins for invasion, such as SopB, SopD
and SopE2. These effectors are located outside of SPI-1 but are
translocated in a SPI-1-dependent manner. S. Typhimurium sopB,
sopD and sopE2 tagged (3xFLAG) strains and their derivative Ddam
were used during the experiments. The expression and secretion of
these effectors were determined in vitro, under SPI-1 culture
conditions, analyzing bacterial pellets and culture supernatants,
respectively. Tagged proteins were examined by SDS-page and
immunoblotting with anti-FLAG antibodies. Western blot results
showed an impaired SopB, SopD and SopE2 expression and
secretion in dam mutants with respect to the parental strain (p <
0.05). These results were further confirmed by QRT-PCR showing
that sopB, sopD and sopE2 genes transcription were two or threefold
lower in dam mutants compared to wild type strain. Taken
together, our results demonstrate that Dam methylation modulates
the expression and secretion of SopB, SopD and SopE2.