کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1938900 1050749 2007 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Enzymatic formation of unnatural cytokinin analogs by adenylate isopentenyltransferase from mulberry
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
Enzymatic formation of unnatural cytokinin analogs by adenylate isopentenyltransferase from mulberry
چکیده انگلیسی

A cDNA encoding adenylate isopentenyltransferase (AIPT) was cloned from young leaves of mulberry (Morus alba) by a homology-based RT-PCR. A recombinant enzyme expressed in Escherichia coli catalyzed prenyl transfer from DMAPP to the N6 amino group of ADP and ATP, respectively, while AMP was a poor substrate of the enzyme. Interestingly, M. alba AIPT also accepted dADP, dATP, CDP, and GDP as the prenyl acceptors, and IPP, HMBPP, and GPP as the prenyl donors, to produce a series of cytokinin analogs. In particular, it was remarkable that the enzyme accepted HMBPP to produce trans-zeatin riboside phosphates, which suggested that trans-zeatin may be also produced from adenosine phosphates and HMBPP. Finally, alanine-scanning mutagenesis of conserved D49, Y54, F93, F120, Y153, F157, W159, Y170, Y217, and Q255, resulted in significant loss of enzyme activity except Y170A, confirming the functional and structural importance of the residues.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochemical and Biophysical Research Communications - Volume 355, Issue 3, 13 April 2007, Pages 795–800
نویسندگان
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