trinuclear Fe binding site located at the bottom of the HD-GYP domain cavity formed by the two claws of the open chela. Residues E185, H189, H221, D222, H250, H276, H277, and D305 are involved in metal binding
heme protein with remarkable stability against electron transfer to O2. Oxy-enzyme is only 30% oxidized to the ferric form after 8 h in airsaturated Tris buffer pH 8.0, 23°C
the enzyme can accommodate both di- and trimetal active sites. An as-isolated iron-containing TM0186 has an oxo/carboxylato-bridged diferric site, and the reduced diferrous form is necessary and sufficient to catalyze conversion of cyclic di-GMP to 5'-phosphoguanylyl(3',5')guanosine. Similar cyclic di-GMP phosphodiesterase activities are obtained with divalent iron or manganese. A Glu residue conserved in a subset of homologous enzymes is required for formation of the trimetal site and can also serve as a labile ligand to the dimetal site
the enzyme can accommodate both di- and trimetal active sites. An as-isolated iron-containing TM0186 has an oxo/carboxylato-bridged diferric site, and the reduced diferrous form is necessary and sufficient to catalyze conversion of cyclic di-GMP to 5'-phosphoguanylyl(3',5')guanosine. Similar cyclic di-GMP phosphodiesterase activities are obtained with divalent iron or manganese. A Glu residue conserved in a subset of homologous enzymes is required for formation of the trimetal site and can also serve as a labile ligand to the dimetal site