کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2188681 1096181 2007 16 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Structural Insight into Concerted Inhibition of α2β2-Type Aspartate Kinase from Corynebacterium glutamicum
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی بیولوژی سلول
پیش نمایش صفحه اول مقاله
Structural Insight into Concerted Inhibition of α2β2-Type Aspartate Kinase from Corynebacterium glutamicum
چکیده انگلیسی

Aspartate kinase (AK) catalyzes the first step of the biosynthesis of the aspartic acid family amino acids, and is regulated via feedback inhibition by end-products including Thr and Lys. To elucidate the mechanism of this inhibition, we determined the crystal structure of the regulatory subunit of AK from Corynebacterium glutamicum at 1.58 Å resolution in the Thr-binding form, the first crystal structure of the regulatory subunit of α2β2-type AK. The regulatory subunit contains two ACT domain motifs per monomer and is arranged as a dimer. Two non-equivalent ACT domains from different chains form an effector-binding unit that binds a single Thr molecule, and the resulting two effector-binding units of the dimer associate perpendicularly in a face-to-face manner. The regulatory subunit is a monomer in the absence of Thr but becomes a dimer by adding Thr. The dimerization is eliminated in mutant AKs with changes in the Thr-binding region, suggesting that the dimerization induced by Thr binding is a key step in the inhibitory mechanism of AK from C. glutamicum. A putative Lys-binding site and the inhibitory mechanism of CgAK are discussed.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Biology - Volume 368, Issue 2, 27 April 2007, Pages 521–536
نویسندگان
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