کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
9899204 | 1543768 | 2005 | 10 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Molecular evolution of the lysine decarboxylase-defective phenotype in Shigella sonnei
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موضوعات مرتبط
علوم زیستی و بیوفناوری
بیوشیمی، ژنتیک و زیست شناسی مولکولی
بیوشیمی، ژنتیک و زیست شناسی مولکولی (عمومی)
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Molecular evolution of the lysine decarboxylase-defective phenotype in Shigella sonnei Molecular evolution of the lysine decarboxylase-defective phenotype in Shigella sonnei](/preview/png/9899204.png)
چکیده انگلیسی
Shigella, the etiological agent of the bacillary dysentery, belongs to the extremely diverse species of Escherichia coli. In the evolutionary route of Shigella from commensal E. coli ancestors towards a pathogenic lifestyle, the critical events have been the acquisition of the pINV plasmid, through horizontal transfer and the inactivation of pre-existing genes. These so-called pathoadaptive mutations affect the expression of genes negatively interfering with the newly acquired functions necessary for the colonization of the host niche. Cadaverine, a small polyamine resulting from decarboxylation of lysine, has been shown to hamper the full expression of Shigella invasiveness mainly by altering the inflammatory response. Recent analysis of the evolution of the Shigella and enteroinvasive E. coli (EIEC) cad region indicates that silencing of the cad locus has been attained with several strategies. The increasing relevance of S. sonnei in both, developing and industrial countries, prompted us to analyze the molecular origin of the LDCâ phenotype in these strains. The results obtained on several S. sonnei strains reveal that despite the difference in geographic origin and antibiotic resistance patterns, all the strains have undergone the same modifications. Multiple IS insertions into the cadBA operon have interrupted gene continuity without inducing deletions or inversions of the cadA and cadB genes which are remained entirely conserved. Moreover, by functional analysis we show that all the strains carry a defective cadC gene, thus strengthening the hypothesis that inactivation of the regulatory cadC gene might have been the first step towards a complete lack of the cad locus.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Medical Microbiology - Volume 294, Issue 8, 4 March 2005, Pages 503-512
Journal: International Journal of Medical Microbiology - Volume 294, Issue 8, 4 March 2005, Pages 503-512
نویسندگان
Mariassunta Casalino, Maria Carmela Latella, Gianni Prosseda, Paolo Ceccarini, Francine Grimont, Bianca Colonna,