کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4516213 1322348 2010 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The first characterised wheat (Triticum aestivum L.) member of the nudix hydrolase family shows specificity for NAD(P)(H) and FAD
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم زراعت و اصلاح نباتات
پیش نمایش صفحه اول مقاله
The first characterised wheat (Triticum aestivum L.) member of the nudix hydrolase family shows specificity for NAD(P)(H) and FAD
چکیده انگلیسی

We cloned the first nudix hydrolase of wheat (Triticum aestivum L.) (TaNUDT1) and expressed it using Escherichia coli as expression host. Properties of the purified His6-tagged protein were studied. The sequence codes for a nudix hydrolase with a molecular mass of around 43x103 and a predicted pI of 5.68. The characteristic residues of the nudix box were highly conserved in the wheat enzyme sequence, and TaNUDT1 is most probably targeted to the peroxisomes. In the presence of dithiothreitol and MnCl2, the enzyme hydrolyses the nicotinamide coenzymes NAD(P)(H) as could be predicted by the presence of a conserved amino acid array C-terminal to the nudix box, and the enzyme has higher affinity towards the reduced forms of the coenzymes. In light of previous reports of nudix enzymes and the physiological concentration of their substrates, we found its Km values towards some of the coenzymes to be relatively high. As NAD(P)(H) and FAD play crucial roles in cell metabolism, extensive hydrolysis could be detrimental to cell functioning. We speculate that a decreased enzyme affinity may point to a built-in restriction on coenzyme hydrolysis in vivo. Furthermore, by hydrolysing the cofactors of several redox enzymes, this enzyme may well affect several wheat based processes.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Cereal Science - Volume 51, Issue 3, May 2010, Pages 319–325
نویسندگان
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