کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1179115 962758 2008 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Multistate folding of a hyperthermostable Fe-superoxide dismutase (TcSOD) in guanidinium hydrochloride: The importance of the quaternary structure
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Multistate folding of a hyperthermostable Fe-superoxide dismutase (TcSOD) in guanidinium hydrochloride: The importance of the quaternary structure
چکیده انگلیسی

Superoxide dismutases (SODs), which are the first line of cellular defense against the toxic effects of reactive oxygen species, are metalloenzymes that catalyze the disproportionation of superoxide radicals to produce oxygen and hydrogen peroxide. Although much effort has been devoted to the folding mechanisms of Cu/Zn-SODs, little is known about the folding of Fe-SODs. In this research, the equilibrium unfolding and refolding of TcSOD, a tetrameric hyperthermostable Fe-SOD, were investigated by circular dichroism, intrinsic fluorescence, ANS fluorescence, size-exclusion chromatography and cross-linking experiments. The results herein suggested that the guanidine hydrochloride-induced unfolding of TcSOD involved a stable monomeric intermediate and a possible tetrameric intermediate. The Gibbs free energy of TcSOD dissociation was about 3-fold larger than that of the monomeric intermediate unfolding, which suggested that the quaternary structure plays a crucial role in TcSOD stability. A comparison of the thermodynamic parameters between TcSOD and other SODs also suggested that the stability of quaternary structure might be responsible for the hyperthemostability of TcSOD.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics - Volume 1784, Issue 3, March 2008, Pages 445–454
نویسندگان
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