کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5501851 | 1534942 | 2016 | 39 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
PrxQ B from Mycobacterium tuberculosis is a monomeric, thioredoxin-dependent and highly efficient fatty acid hydroperoxide reductase
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کلمات کلیدی
FPLCCBAPMSFDTNBM. tuberculosisHRPPRXDTTIPTGBHTSECcholesteryl linoleate hydroperoxide15-HPETETris(2-Carboxyethyl) phosphineDTPAisopropyl-1-thio-β-d-galactopyranoside - 1-isopropyl-1-thio-β-d-galactopyranosideDMSO - DMSOt-BOOH - T-BOOHHydrogen peroxide - آب اکسیژنهthioredoxin - تیرودوکسینDiethylenetriaminepentaacetic acid - دی اتیلنتریمین پنتا اسیدهای اسیدClassical molecular dynamics - دینامیک مولکولی کلاسیکdithiothreitol - دیتیوتریتولDimethyl sulfoxide - دیمتیل سولفواکسیدcircular dichroism - رنگ تابی دورانیTCEP - ساکتfast protein liquid chromatography - سریع کروماتوگرافی مایع پروتئینphenylmethylsulfonyl fluoride - فنیل متیل سولفونیل فلورایدMALS - مالشMycobacterium tuberculosis - مایکوباکتریوم توبرکلوزیسXylenol orange - نارگیل XylenolFatty acid hydroperoxides - هیدروپراکسید اسید چربtert-butyl hydroperoxide - هیدروپراکسید تری بوتیلcumene hydroperoxide - هیدروپراکسید کومنH2O2 - هیدروژن پراکسیدbutylated hydroxytoluene - هیدروکسی تورولین باتلاقیHorseradish peroxidase - پراکسیداز هوررادیشMultiangle light scattering - پراکندگی نور چندگانهPeroxiredoxin - پروکسی ردوکسینPeroxynitrite - پروکسی نیتریتSize exclusion chromatography - کروماتوگرافی اندازهای طردی
موضوعات مرتبط
علوم زیستی و بیوفناوری
بیوشیمی، ژنتیک و زیست شناسی مولکولی
سالمندی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
Mycobacterium tuberculosis (M. tuberculosis) is the intracellular bacterium responsible for tuberculosis disease (TD). Inside the phagosomes of activated macrophages, M. tuberculosis is exposed to cytotoxic hydroperoxides such as hydrogen peroxide, fatty acid hydroperoxides and peroxynitrite. Thus, the characterization of the bacterial antioxidant systems could facilitate novel drug developments. In this work, we characterized the product of the gene Rv1608c from M. tuberculosis, which according to sequence homology had been annotated as a putative peroxiredoxin of the peroxiredoxin Q subfamily (PrxQ B from M. tuberculosis or MtPrxQ B). The protein has been reported to be essential for M. tuberculosis growth in cholesterol-rich medium. We demonstrated the M. tuberculosis thioredoxin B/C-dependent peroxidase activity of MtPrxQ B, which acted as a two-cysteine peroxiredoxin that could function, although less efficiently, using a one-cysteine mechanism. Through steady-state and competition kinetic analysis, we proved that the net forward rate constant of MtPrxQ B reaction was 3 orders of magnitude faster for fatty acid hydroperoxides than for hydrogen peroxide (3Ã106vs 6Ã103Â Mâ1Â sâ1, respectively), while the rate constant of peroxynitrite reduction was (0.6â1.4) Ã106Â Mâ1Â sâ1 at pH 7.4. The enzyme lacked activity towards cholesterol hydroperoxides solubilized in sodium deoxycholate. Both thioredoxin B and C rapidly reduced the oxidized form of MtPrxQ B, with rates constants of 0.5Ã106 and 1Ã106Â Mâ1Â sâ1, respectively. Our data indicated that MtPrxQ B is monomeric in solution both under reduced and oxidized states. In spite of the similar hydrodynamic behavior the reduced and oxidized forms of the protein showed important structural differences that were reflected in the protein circular dichroism spectra.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Free Radical Biology and Medicine - Volume 101, December 2016, Pages 249-260
Journal: Free Radical Biology and Medicine - Volume 101, December 2016, Pages 249-260
نویسندگان
AnÃbal M. Reyes, Diego S. Vazquez, Ari Zeida, MartÃn Hugo, M. Dolores Piñeyro, MarÃa Inés De Armas, DarÃo Estrin, Rafael Radi, Javier Santos, Madia Trujillo,