title: Tuned by metals: the TET peptidase activity is controlled by 3 metal binding sites.
abstract: TET aminopeptidases are dodecameric particles shared in the three life domains involved in various biological processes, from carbon source provider in archaea to eye-pressure regulation in humans. Each subunit contains a dinuclear metal site (M1 and M2) responsible for the enzyme catalytic activity. However, the role of each metal ion is still uncharacterized. Noteworthy, while mesophilic TETs are activated by Mn(2+), hyperthermophilic TETs prefers Co(2+). Here, by means of anomalous x-ray crystallography and enzyme kinetics measurements of the TET3 aminopeptidase from the hyperthermophilic organism Pyrococcus furiosus (PfTET3), we show that M2 hosts the catalytic activity of the enzyme, while M1 stabilizes the TET3 quaternary structure and controls the active site flexibility in a temperature dependent manner. A new third metal site (M3) was found in the substrate binding pocket, modulating the PfTET3 substrate preferences. These data show that TET activity is tuned by the molecular interplay among three metal sites.
authors: CNRS, IBS, F-38027 Grenoble, France.|CEA, DSV, IBS, F-38027 Grenoble, France.|Univ. Grenoble Alpes, Institut de Biologie Structurale (IBS), F-38027 Grenoble, France.
authors: Matteo
authors: M
authors: Colombo
authors: CNRS, IBS, F-38027 Grenoble, France.|CEA, DSV, IBS, F-38027 Grenoble, France.|Univ. Grenoble Alpes, Institut de Biologie Structurale (IBS), F-38027 Grenoble, France.
authors: Eric
authors: E
authors: Girard
authors: CNRS, IBS, F-38027 Grenoble, France.|CEA, DSV, IBS, F-38027 Grenoble, France.|Univ. Grenoble Alpes, Institut de Biologie Structurale (IBS), F-38027 Grenoble, France.
authors: Bruno
authors: B
authors: Franzetti
mesh_terms: D000626:Aminopeptidases / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D002384:Catalysis; D020134:Catalytic Domain; D003300:Copper / Q000737:chemistry; D018360:Crystallography, X-Ray; D004789:Enzyme Activation; D008670:Metals / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D008968:Molecular Conformation; D011485:Protein Binding; D011487:Protein Conformation; D055503:Protein Multimerization; D013696:Temperature
chemical_list: D008670:Metals; D003300:Copper; D000626:Aminopeptidases