6.3.4.2 ? x * 100000, SDS-PAGE 662806 6.3.4.2 ? x * 56180, calculation from nucleotide sequence 648966 6.3.4.2 ? x * 59500, calculated -, 746547 6.3.4.2 ? x * 64622, calculation from nucleotide sequence 648966 6.3.4.2 ? x * 64783, calculation from nucleotide sequence 648966 6.3.4.2 ? x * 65514, calculation from nucleotide sequence 648966 6.3.4.2 ? x * 65678, calculation from nucleotide sequence 648966 6.3.4.2 ? x * 66705,calculation from nucleotide sequence 648966 6.3.4.2 ? x * 66710, calculation from nucleotide sequence 648966 6.3.4.2 ? x * 70000, SDS-PAGE 727139, 727427, 728541 6.3.4.2 dimer 2 * 66000, SDS-PAGE 648982 6.3.4.2 dimer crystallization data and sedimentation-ultracentrifugation experiments 713658 6.3.4.2 dimer the enzyme is a dimer of 108000 Da, the dimer associates to form a tetramer in the presence of either ATP or UTP -, 648981 6.3.4.2 additional information binding of the substrates ATP and UTP, or the product CTP, promotes oligomerization of CTPS from inactive dimers to active tetramers, Gly142 is critical for nucleotide-dependent oligomerization of CTPS to active tetramers. Oligomerization of Gly mutant enzymes, overview 690817 6.3.4.2 additional information CTP synthetase oligomerizes to a tetramer in the presence of its substrates UTP and ATP 648999 6.3.4.2 additional information the enzyme can dissociate to an apparently inactive monomer. The dissociation is reversible and the rate of association is slow 648984 6.3.4.2 tetramer - 648968 6.3.4.2 tetramer 2 * 60000 648977 6.3.4.2 tetramer 4 * 50000, SDS-PAGE 648984 6.3.4.2 tetramer 4 * 52000, enzyme exists as tetramer in presence of UTP, Mg2+ and ATP 648989, 648992 6.3.4.2 tetramer 4 * 68000, SDS-PAGE 648999 6.3.4.2 tetramer conserved Gly142 is critical for tetramerization, overview 690817 6.3.4.2 tetramer the enzyme exists as an inactive dimer in the absence of ATP and UTP. In the presence of saturating concentrations of ATP and UTP, the CTP synthetase protein exists as an active tetramer. Increasing concentrations of ATP and UTP cause a dose-dependent conversion of the dimeric species to a tetramer. Tetramerization is dependent on UTP and Mg2+ ions. ATP facilitates the UTP-dependent teramerization of CTP synthetase by a mechanism that involves the ATP-dependent phosphorylation of UTP catalyzed by the enzyme 648975 6.3.4.2 tetramer UTP and ATP are responsible for the tetramerization and activation of the inactive dimeric form of the enzyme. UTP is absolutely required for the tatramerization of the enzyme when ATP is present at a saturating concentration 648978