| Autor: |
Farizano JV; Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT, and Instituto de Química Biológica 'Dr. Bernabé Bloj', Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI - San, Miguel de Tucumán, Argentina., García-Pastor L; Departamento de Genética, Universidad de Sevilla, Apartado 1095, 41080 Sevilla, Spain., Casadesús J; Departamento de Genética, Universidad de Sevilla, Apartado 1095, 41080 Sevilla, Spain., Delgado MA; Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT, and Instituto de Química Biológica 'Dr. Bernabé Bloj', Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI - San, Miguel de Tucumán, Argentina. |
| Abstrakt: |
In Salmonella enterica serovar Typhimurium, the RcsCDB regulatory system controls the expression of genes involved in synthesis of colanic acid, formation of flagella and virulence. Here, we show that activation of the RcsCDB system downregulates expression of std, an operon that encodes fimbriae involved in Salmonella attachment to the mucus layer in the large intestine. Bioinformatic analysis predicts the existence of an RcsB-binding site located 180 bp upstream to the +1 transcription start site of the std promoter, and electrophoretic mobility shift assays confirm that RcsB binds the std promoter region in vitro . This study adds RcsB to the list of regulators of std transcription and provides an example of modulation of fimbriae synthesis by a signal transduction system. |
