INVESTIGADORES
DELGADO Monica Alejandra
congresos y reuniones científicas
Título:
Study of the sbmA gen regulation in Escherichia coli
Autor/es:
CORBALÁN, N; DELGADO MA; VINCENT, PAULA
Lugar:
Mar del PLata
Reunión:
Congreso; XLIII Annual Meeting of the Argentine Society for Biochemistry and Molecular Biology; 2007
Institución organizadora:
SAIB
Resumen:
Study of the sbmA gen regulation in Escherichia coli Corbalán, N; Delgado, M. A.; and Vincent, P. Dpto Bioqca de la Nutrición-INSIBIO e Inst. Qca Biológica CONICET-UNT. Chacabuco 461 (4000) Tucumán, pvincent@fbqf.unt.edu.ar E. coli SbmA transports MccB17, MccJ25, and bleomycin into the cell cytoplasm. Homologs of the sbmA gene are found in a variety of bacteria suggesting an important physiological role might exist for these genes however it remain unknown. In this work we described the study of the sbmA regulation and the sbmA mutant sensitivity to different agents. Using the GPS bioinformatical program, we demonstrated that the SlyA regulator has a putative binding site on the sbmA promotor region. To confirm these results we performed b-galactosidases assays, and found that sbmA transcription is negatively regulated by SlyA.  We also probed the expression in conditions of MccJ25 accumulation studying sbmA::lacZ expression in a tolC mutant. Interesting, in the absent of the antibiotic we still observed high level of b-galactosidase activity, indicating a positive regulation by tolC mutation. We also observed that sbmA is expressed mainly during the stationary phase and this expression levels was increased when the mutant growth in minimal medium containing low Mg2+ concentration. We only found a partial resistance to polymyxin B in sbmA mutant when the sensitivity of this strain was probed to several agents. Ours preliminary results led us to propose a hypotetical regulation of sbmA by SlyA and PhoP/PhoQ in E. coli.