کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10752408 1050327 2015 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
CysB-dependent upregulation of the Salmonella Typhimurium cysJIH operon in response to antimicrobial compounds that induce oxidative stress
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
CysB-dependent upregulation of the Salmonella Typhimurium cysJIH operon in response to antimicrobial compounds that induce oxidative stress
چکیده انگلیسی
It has been proposed that some antibiotics exert additional damage through reactive oxygen species (ROS) production. Since H2S protects neurons and cardiac muscle from oxidative stress, it has been hypothesized that bacterial H2S might, similarly, be a cellular protector against antibiotics. In Enterobacteriaceae, H2S can be produced by the cysJIH pathway, which uses sulfate as the sulfur source. CysB, in turn, is a positive regulator of cysJIH. At present, the role of S. Typhimurium cysJIH operon in the protection to reactive oxygen species (ROS) induced by antimicrobial compounds remains to be elucidated. In this work, we evaluated the role of cysJIH and cysB in ROS accumulation, superoxide dismutase (SOD) activity, reduced thiol accumulation, and H2S accumulation in S. Typhimurium, cultured in either sulfate or cysteine as the sole sulfur source. Furthermore, we assessed the effects of the addition of ceftriaxone (CEF) and menadione (MEN) in these same parameters. In sulfate as the sole sulfur source, we found that the cysJIH operon and the cysB gene were required to full growth in minimal media, independently on the addition of CEF or MEN. Most importantly, both cysJIH and cysB contributed to diminish ROS levels, increase the SOD activity, increase the reduced thiols, and increase the H2S levels in presence of CEF or MEN. Moreover, the cysJIH operon exhibited a CysB-dependent upregulation in presence of these two antimicrobials compounds. On the other hand, when cysteine was used as the sole sulfur source, we found that cysJIH operon was completely negligible, were only cysB exhibited similar phenotypes than the described for sulfate as sulfur source. Unexpectedly, CysB downregulated cysJIH operon when cysteine was used instead of sulfate, suggesting a complex regulation of this system.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochemical and Biophysical Research Communications - Volume 458, Issue 1, 27 February 2015, Pages 46-51
نویسندگان
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