2D S3 TROSY NOESY

Ref.:
A.Meissner, and O.W.Sørensen J.Magn.Reson. 140, 499-503 (1999). (Suppression of Diagonal Peaks in TROSY-Type 1H NMR NOESY Spectra of 15N-Labeled Proteins)
2D S3E TROSY NOESY (top) and 2D S3CT TROSY NOESY (bottom) pulse sequences with diagonal peak suppression. The latter yields the best diagonal peak suppression.
Delays:  = (2JNH)-1;  = gradient delay; m = mixing time.
Phases:' =  + /2, ' =  + /2, and " =  + . For all odd-numbered scans the phase  is x and the left dashed  pulse on the S channel is applied whilst for all even-numbered scans  is y and the right dashed  pulse on the S channel is applied with opposite receiver phase.
S3E TROSY NOESY pulse sequence (top):
Phases for Varian Unity Inova:  = y; 1 = {/4, /4, /4, /4}, 2 = {0, 0, /2, /2}, 3 = {0, 0, 0, 0},  = {0, /2, 0, /2} and receiver {0, , , 0}.
Phases for Bruker DRX:  = x; 1 = {/4, /4, /4, /4}, 2 = {0, 0, /2, /2}, 3 = {0, 0, 0, 0},  = {0, /2, 0, /2} and receiver {0, , , 0}.
S3CT TROSY NOESY pulse sequence (bottom):
is cycled to create two data sets: A:  = {0, 0, , } and B:  = {/2, /2, 3/2, 3/2} both with  = {0, /2, 0, /2} and receiver {0, , 0, }. A-B selects the TROSY resonances in F1.

For water flip back it is crucial to set the transmitter frequency of the protons right on the water resonance.

Varian:

2D S3E TROSY NOESY: Set parameter exp = 'e' and select = 'a'

2D S3CT TROSY NOESY: Set parameter exp = 'c' and select = 'a','b'

To generate a selective water pulse shape, copy water_sc.inp to your $HOME/vnmrsys/shapelib directory, adjust ref_pwr and ref_pw90 according to your proton pulse calibration and type the command: Pbox -f water_sc.inp (for 2D S3E TROSY NOESY Pbox -f water45_sc.inp is also required)

An output like
>>> Set pulse width to 1.0000 ms <<<
>>> Set pulse power to 21 dB <<<
appears.

Remember to change the parameters pwater (pulse width in us) and pwaterlvl (pulse power).

Processing of 2D S3CT TROSY NOESY:

Combination of interleaved recorded subspectra with array = 'phase,select'

Protocol 1: (using dia_noesy_sort.c sorting routine for data set combination)

  • change into the directory of your data set (cd name.fid)
  • rename the fid file >mv fid fid_orig<
  • run the dia_noesy_sort sorting routine >dia_noesy_sort fid_orig fid ni np wf< (wf weighting factor for data set combination subspectrum a : subspectrum b = 1 : wf, adjust wf to give optimum diagonal suppression (e.g.: wf = 0.995))
  • use your usual software for processing and phase correction
dia_noesy_sort.c installation:
change to the directory with the dia_noesy_sort.c file
type cc dia_noesy_sort.c -o $HOME/bin/dia_noesy_sort
this will compile the program and save the executable file in the $HOME/bin directory. Make sure the directory exists or choose another location. Make also sure your PATH environment variable contains the directory you are using.

Protocol 2: (using Xwinnmr for data set combination)

  • use vconv to convert the data set
  • change 1s td to half of its value
  • change 2s td to double of its value
  • change 1s sfo1 to 2s sfo1 (get the frequency axis in F1 right)
  • adjust processing parameter in edp (SI (F2,F1), MC2 = States, SSB = 2, F2: TDeff = np, Reverse = TRUE, strip transformation is possible)

    • if d2 was set to 1/sw1 no phase correction is required in F1 by using linear back prediction of 2 points in F1 (ME_mod = LPbc, NCOEF = 128, F1: TDoff = -2)
  • xfb with F2: TDoff = 0
  • copy data set to a new processing number (wrp 2, re 2)
  • xfb in new processing number using F2: TDoff = np
  • change to first processing number and change PROCNO2 = 2 in edc2
  • set alpha = 0.5 and gamma = -0.5 (change the values, if different weighting of the subspectra is required)
  • add subspectra (add2d)
  • do phase correction in F2
(protocol tested with Xwinnmr2.6 patchlevel 4)

Program tested on: Varian Unity Inova, Vnmr6.1B, Pbox6.1C, Solaris7

Content
Pulse sequence:  dia_noesy.c
Parameters:      dia_noesy.par
Pbox input file: water_sc.inp
                 water45_sc.inp
Editing routine: dia_noesy_sort.c

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Bruker:

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Document: 3D TROSY (H)CCH (index.shtml)
Last modified: 2005-12-19