Regulation of the Expression of the Vibrio parahaemolyticus peuA Gene Encoding an Alternative Ferric Enterobactin ReceptorReportar como inadecuado




Regulation of the Expression of the Vibrio parahaemolyticus peuA Gene Encoding an Alternative Ferric Enterobactin Receptor - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

A pvsB-vctA-irgA triple deletion mutant of Vibrio parahaemolyticus can utilize enterobactin under iron-limiting conditions by inducing a previously undescribed receptor, PeuA VPA0150, in response to extracellular alkaline pH and enterobactin. In silico analyses revealed the existence of a two-component regulatory system operon, peuRS, immediately upstream of peuA, which constitutes an operon with the TonB2 system genes. Both the peuRS and peuA-tonB2 operons were found to be upregulated under iron-limiting conditions in a ferric uptake regulator Fur-dependent manner. The involvement of peuA and peuRS in enterobactin utilization was analyzed by complementation experiments using deletion mutants. Primer extension analysis indicated that, under iron-limiting conditions, the transcription of peuA was initiated from the +1 site at pH 7.0 and from both the +1 and +39 sites at pH 8.0 in the presence of enterobactin. The +39 transcript was absent from the peuRS deletion mutant. Secondary structure prediction of their 5′-untranslated regions suggested that translation initiation is blocked in the +1 transcript, but not in the +39 transcript. Consistent with this, in vitro translation analysis demonstrated that production of PeuA was determined only by the +39 transcript. These studies establish a novel gene regulation mechanism in which the two-component regulatory system PeuRS enhances expression of the alternative +39 transcript that possesses non-inhibitory structure, allowing the peuA expression to be regulated at the translation stage.



Autor: Tomotaka Tanabe , Ayaka Kato, Keiichi Shiuchi, Katsushiro Miyamoto, Hiroshi Tsujibo, Jun Maki, Shigeo Yamamoto, Tatsuya Funahashi

Fuente: http://plos.srce.hr/



DESCARGAR PDF




Documentos relacionados