Proteomics analysis of the Francisella tularensis LVS response to iron restriction: induction of the F. tularensis pathogenicity island proteins IglABC.
نویسندگان
چکیده
Francisella tularensis is a highly virulent, facultative intracellular pathogen that causes tularemia in humans and animals. Although it is one of the most infectious bacterial pathogens, little is known about its virulence mechanisms. In this study, the response of F. tularensis live vaccine strain to iron depletion, which simulates the environment within the host, was investigated. In order to detect alterations in protein synthesis, metabolic labeling, followed by 2D-PAGE analysis was used. Globally, 141 protein spots were detected whose levels were significantly altered in the iron-restricted medium. About 65% of the spots were successfully identified using mass spectrometric approaches. Importantly, among the proteins produced at an increased level during iron-limited growth, three proteins were found encoded by the igl operon, located in the F. tularensis pathogenicity island I (FPI). Of these, the IglC and IglA proteins were previously reported to be necessary for full virulence of F. tularensis. These results, obtained at the proteome level, support and confirm recently published data showing that the igl operon genes are transcribed in response to iron limitation.
منابع مشابه
Identification of Francisella tularensis genes affected by iron limitation.
Cells of an attenuated live vaccine strain (LVS) of F. tularensis grown under iron-restricted conditions were found to contain increased quantities of several proteins relative to cells of this same strain grown under iron-replete conditions. Mass spectrometric analysis identified two of these proteins as IglC and PdpB, both of which are encoded by genes located in a previously identified patho...
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عنوان ژورنال:
- FEMS microbiology letters
دوره 269 1 شماره
صفحات -
تاریخ انتشار 2007