Heteronuclear three-dimensional NMR spectroscopy applied to CMP-KDO synthetase (27.5 kD).

A heteronuclear three-dimensional NMR experiment has been applied to uniformly 15N-labeled CMP-KDO synthetase (CTP:3-deoxy-D-manno-octulosonate cytidylyl transferase; E.C. 2.7.7.38) complexed with an inhibitor and CTP. Using this 3D technique, the 2D NOE spectrum of the ternary complex was dramatically simplified by editing with respect to the 15N frequencies of the labeled enzyme. This 3D NMR method is a useful tool for resolving spectral overlap and is particularly well-suited for NMR studies of large molecules which are difficult to study by conventional 2D NMR techniques.