Madrid, CristinaNieto Liñán, José MiguelPaytubi, SòniaFalconi, MaurizioGualerzi, Claudio O.Juárez, Antonio2013-12-112013-12-112002-09Madrid, C., Nieto Liñán, J.M., Paytubi, S., Falconi, M., Gualerzi, C.O.: "Temperature- and H-NS-Dependent Regulation of a Plasmid-Encoded Virulence Operon Expressing Escherichia coli Hemolysin". Journal of Bacteriology. Vol. 184, No. 18, págs. 5058–5066 (2002). ISSN 0021-91930021-91931098-5530 (electrónico)http://hdl.handle.net/10272/7491Proteins H-NS and Hha form a nucleoprotein complex that modulates expression of the thermoregulated hly operon of Escherichia coli. We have been able to identify two H-NS binding sites in the hly regulatory region. One of them partially overlaps the promoter region (site II), and the other is located about 2 kbp upstream (site I). In contrast, Hha protein did not show any preference for specific sequences. In vitro, temperature influences the affinity of H-NS for a DNA fragment containing both binding sites and H-NS-mediated repression of hly operon transcription. Deletion analysis of the hly regulatory region confirms the relevance of site I for thermoregulation of this operon. We present a model to explain the temperature-modulated repression of the hly operon, based on the experiments reported here and other, preexisting data.engAtribución-NoComercial-SinDerivadas 3.0 Españahttp://creativecommons.org/licenses/by-nc-nd/3.0/es/H-NSHhaEscherichia colijournal article10.1128/JB.184.18.5058–5066.2002open access