3D 1H-15N HMQC-NOESY-HMQC experiment

Description 3D 1H-15N HMQC-NOESY-HMQC experiment, phase cycle reduced by use of gradients, H2O magnetization returned to equilibrium prior to acquisition, magic angle gradients.
References P. Andersson et al, J. Biol. NMR, 11, 279-288 (1998),
Ikura et al., J. Am. Chem. Soc., 112, 9020-9022 (1990),
Frenkiel et al., J. Magn. Reson., 90, 420-425 (1990).
See also: 3D NMR
Pulse Sequence NNH_NOESY.bf
Parameter Set NNH_NOESY.bf
Parameters to be Adjusted p1, d8, 1 sw, sw, o2

Timing diagram for HNH_NOESY.bf

Acquisition

  1. Acquire a 1D 1H data set and a 2D 1H-15N HSQC data set, determine p1 (1H 90° pulse at pl1=0, 9 to 13 µs), SW (1H sweepwidth), 1 SW (15N sweepwidth), o2 (15N offset).

  2. Create a 3D experiment and load parameter set HNH_NOESY.bf. Set parameters p1, d8 (mixing time, 50-200 ms), 1 SW = SW (1H), 2 SW (15N). Type expt to check acquisition time.

  3. Set pulprog = noe_setup.bf. Set rg = 32. In gs mode adjust sp1 and phcor13 iteratively to optimize the water flip-back pulse, i.e, minimize the FID.

  4. Reset pulprog = NNH_NOESY.bf. Set rg = 1024. Type zg to acquire a 3D spectrum.

Processing

  1. Adjust phase in F3... Type rser 1 to read the first FID. Process and phase correct as a normal 1D spectrum. When leaving the phase correction utility choose the Save as 2D & return option. Click the 3D button to get back to your NOESY-HSQC data set.

  2. Type tf3 n <ret>, tf2 n <ret>, tf1 n <ret> to process your data set.

  3. Type edlev and choose a single contour level (try 10,000,000 initially). Click display to calculate contours. You may have to choose a higher contour level and try again if this calculation fails.

  4. The 3D manipulation buttons are now active. Click scan to step through your data and examine individual planes.