کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1926266 1536448 2009 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Interactions across the interface contribute the stability of homodimeric 3α-hydroxysteroid dehydrogenase/carbonyl reductase
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
Interactions across the interface contribute the stability of homodimeric 3α-hydroxysteroid dehydrogenase/carbonyl reductase
چکیده انگلیسی

The dimerization of 3α-hydroxysteroid dehydrogenase/carbonyl reductase was studied by interrupting the salt bridge interactions between D249 and R167 in the dimeric interface. Substitution of alanine, lysine and serine for D249 decreased catalytic efficiency 30, 1400 and 1.4-fold, and lowered the melting temperature 6.9, 5.4 and 7.6 °C, respectively. The mutated enzymes have the dimeric species but the equilibrium between monomer and dimer for these mutants varies from each other, implying that these residues might contribute differently to the dimer stability. Thermal and urea-induced unfolding profiles for wild-type and mutant enzymes appeared as a two-state transition and three-state transition, respectively. In addition, mutation on D249 breaks the salt bridges and causes different effects on the loss of enzymatic activity for D249A, D249K and D249S mutants in the urea-induced unfolding profiles. Hence, D249 at the dimeric interface in 3α-HSD/CR is essential for conformational stability, oligomeric integrity and enzymatic activity.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Archives of Biochemistry and Biophysics - Volume 490, Issue 1, 1 October 2009, Pages 36–41
نویسندگان
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