title: Contribution of the two domains of E. coli 5'-nucleotidase to substrate specificity and catalysis.
abstract: Escherichia coli 5'-nucleotidase, a two-domain enzyme, dephosphorylates various nucleotides with comparable efficiency. We have expressed the two domains individually in E. coli and show by liquid state NMR that they are properly folded. Kinetic characterization reveals that the C-terminal domain, which contains the substrate-binding pocket, is completely inactive while the N-terminal domain with the two-metal-ion-center and the core catalytic residues exhibits significant activity, especially towards substrates with activated phosphate bonds (ATP, ADP, p-nitrophenyl phosphate). In contrast, residues of the C-terminal domain are required for efficient hydrolysis of AMP.
authors: Institute of Bioanalytical Chemistry, Center for Biotechnology and Biomedicine, University of Leipzig, 04103 Leipzig, Germany.
authors: Ulrike
authors: U
authors: Krug
authors: Rica
authors: R
authors: Patzschke
authors: Matthias
authors: M
authors: Zebisch
authors: Jochen
authors: J
authors: Balbach
authors: Norbert
authors: N
authors: Sträter
mesh_terms: D015720:5'-Nucleotidase / Q000737:chemistry*; D000244:Adenosine Diphosphate / Q000737:chemistry; D000249:Adenosine Monophosphate / Q000737:chemistry; D000255:Adenosine Triphosphate / Q000737:chemistry; D020134:Catalytic Domain; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins / Q000737:chemistry*; D006868:Hydrolysis; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D013379:Substrate Specificity
chemical_list: D029968:Escherichia coli Proteins; D000249:Adenosine Monophosphate; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D015720:5'-Nucleotidase