Investigation of the GTP-binding consensus sequences in Escherichia coli adenylosuccinate synthetase and the enzyme's reaction mechanism
نویسنده
چکیده
8 INTRODUCTION 10 MATERIALS AND METHODS 11 RESULTS 14 DISCUSSION 18 REFERENCES 21 CHAPTER 11. REPLACEMENT OF Asp^^^ WITH Asn BY SITEDIRECTED MUTAGENESIS CHANGES THE SUBSTRATE SPECIFICITY OF ESCHERICHIA COLI ADENYLOSUCCINATE SYNTHETASE FROM GUANOSINE 5'-TRIPHOSPHATE TO XANTHOSINE 5'-TRIPHOSPHATE ABSTRACT 28 INTRODUCTION 29 EXPERIMENTAL PROCEDURES 31 RESULTS 32 DISCUSSION 3628 INTRODUCTION 29 EXPERIMENTAL PROCEDURES 31 RESULTS 32 DISCUSSION 36
منابع مشابه
Entrapment of 6-thiophosphoryl-IMP in the active site of crystalline adenylosuccinate synthetase from Escherichia coli.
Crystal structures of adenylosuccinate synthetase from Escherichia coli complexed with Mg2+, 6-thiophosphoryl-IMP, GDP, and hadacidin at 298 and 100 K have been refined to R-factors of 0.171 and 0.206 against data to 2.8 and 2.5 A resolution, respectively. Interactions of GDP, Mg2+ and hadacidin are similar to those observed for the same ligands in the complex of IMP, GDP, NO3-, Mg2+ and hadaci...
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The structure of the P2(1) crystal form of adenylosuccinate synthetase from Escherichia coli has been determined to a resolution of 2.8 A. The refined model for the enzyme gives an R factor of 0.20 and a root-mean-square deviation from expected bond lengths and angles of 0.016 A and 2.27 degrees, respectively. The dominant structural element of each monomer of the homodimer is a central beta-sh...
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