Detecting the "afterglow" of 13C NMR in proteins using multiple receivers.
We show that the weak signal that remains after (13)C-detected experiments (the (13)C "afterglow") can still be measured with high sensitivity by proton detection. This is illustrated by the incorporation of two experiments, 2D (HA)CACO and 3D (HA)CA(CO)NNH, into a single pulse sequence that makes use of two receivers in parallel. In cases where the sensitivity is not limiting, such as applications to small proteins, the inclusion of the projection-reconstruction method permits the recording of both spectra in only 15 min. High-quality data sets for the 143 residue nuclease A inhibitor (2 °C, correlation time 17.5 ns) were obtained in 3 h, illustrating the utility of the method even in studies of moderately sized proteins.
Agilent Technologies, 6 Mead Road, Yarnton, Oxford OX5 1QU, UK. eriks.kupce@agilent.com
Ēriks
Ē
Kupče
Lewis E
LE
Kay
Ray
R
Freeman
D001426:Bacterial Proteins / Q000737:chemistry; D002247:Carbon Isotopes / Q000032:analysis; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D011506:Proteins / Q000737:chemistry*; D011522:Protons
D001426:Bacterial Proteins; D002247:Carbon Isotopes; C106206:NuiA protein, Anabaena; D011506:Proteins; D011522:Protons