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Create a new dataset with edc or, alternatively, increment the experiment number with the iexpno command.MODIFY SPECIFIC PARAMETERSRead the standard parameter set necessary to record a gradient-based sensitivity-enhanced 3D H(CC)(CO)NH experiment by typing rpar HCCCONHGP3D1 all (the hccconhgp3d1 pulse program can be displayed with the edcpul command).
Channel f1 f2 f3 Nucleus 1H 13C 15N Offset o1p o2p o3p Carrier 4.75 ppm 37.9 ppm 115.5 ppm
Update the corresponding pulses and power levels in the acquisition parameters according to the selected solvent/probehead parameters by executing the getprosol command (pulses and power levels must be correctly set by the edprosol command). The following hard and shaped pulses applied on the three channels must be previously calibrated:ACQUISITION
- Hard 90º and 180º 1H pulses via the observe f1 channel (p1 and p2 at pl1).
- 90º degree 1H pulse for broadband DIPSI-2 decoupling via the observe f1 channel (pcpd1 at pl19 using cpdprg1=dipsi2).
- Low power 90º 1H pulse for 1H-13C hetero-TOCSY transfer (using DIPSI-3) via the f1 channel. (p6 (about 25u) at pl10).
- Low power 90º 13C pulse for 1H-13C hetero-TOCSY transfer and 13C-13C TOCSY transfer (using DIPSI-3) via the decoupler f2 channel. (p9=p6 (about 25u) at pl15).
- Selective 90 13C pulses applied on the CA or CO resonances via the decoupler f2 channel (p13 (about 409u) at sp2, using spnam2=G4.256, spoff2=0).This same pulse is also applied to perform time reversed selective 90 pulses (p13 (about 409u) at sp8, using spnam8=G4tr.256, spoff8=0). Similarly, a higher selective pulse is required for selective CA inversion on CA resonances (p24 (about 768u) at sp9, using spnam9=G3.256, spoff9=0).
- Selective 180 13C pulses applied on the CA or CO resonances via the decoupler f2 channel (p14 (about 256u) at sp3, using spnam3=G3.256, spoff3=0).
- Selective 180 13C pulses applied off-resonance on the CO resonances via the decoupler f2 channel (p14 (about 256u) at sp5, using spnam5=G3.256, spoff5=+130 ppm).
- Selective 180 13C pulses applied off-resonance on the CA or CO resonances via the decoupler f2 channel (p14 (about 256u) at sp7, using spnam7=G3.256, spoff7=-130 ppm).
- Hard 90º and 180º 15N pulses via the decoupler f3 channel (p21 and p22 at pl3).
- 90º 15N pulse for GARP decoupling during acquisition via the decoupler f3 channel (pcpd3 at pl16 using cpdprg3=garp).
Otherwhise, all required acquisition parameters can be displayed with the ased command. By default:
Dimension F3 F2 F1 Nucleus 1H 15N 1H TD 2048 40 128 Spectral width NH (14 ppm) N (31.8ppm) 1H (14 ppm) Interpulse delays:
- d21 and d22 are optimized to 1/(2*JCA-CO) (3.4 and 4.5 ms, respectively)
- d23 is optimized to 1/(4*JN-CO) (12 ms)
- d26 is optimized to 1/(4*JN-H) (2.5 ms)
- length of H->C DIPSI = 6m
- length of total C -> C DIPSI = 12m
All other delays are automatically calculated from these values. Gradient parameters are already defined and the user must be set the number of scans and dummy scans (by default, ns=16 and ds=16) as a function of sample concentration. This experiment contains 2 gradients and the standard parameters are already defined with p16 of 1ms, d16=100u, gpnam1-2=sine.100 and the ratio is 80:8.1.
A frecuency list FQ1LIST must be defined (list has to be stored in the directory) on resonance on water signal for the first part but center of NH region for the second part of the experiment.
A frecuency list FQ2LIST must be defined (list has to be stored in the directory) in which the Caliphatic frequency (43 ppm) is set for first part (DIPSI transfer) and the CO frequency (173 ppm) is set for second part.
Start acquisition by rga and zg (the expected experimental time can be observed with the expt command).PROCESSING
Process the recorded data with tf3, tf2 and tf1. The standard processing parameters are set to:PLOT
Dimension F3 F2 F1 SI 2048 256 512 MC2 - echo/antiecho States-TPPI WDW QSINE QSINE QSINE Offset 2 2 2 ME_mod no LPfc LPfc NCOEF 0 32 32
Use XWINPLOT.OBSERVATIONS
It is advisable to store all acquisition and processing parameters (for instance, with the wpar cbcaconh all command) to be used later.OTHER RELATED VERSIONS
Closely related pulse programs are also available:
- hccconhgp3d1.2 (A standard parameter set is available by typing rpar HCCCONHGP3D1.2 all)
- hccconhgp3d2 (A standard parameter set is available by typing rpar HCCCONHGP3D2 all)
- hccconhgp3d3 (A standard parameter set is available by typing rpar HCCCONHGP3D3 all)
List of Related Experiments:
Double-Resonance 1H-13C experiments
Double-Resonance 1H-15N experiments
Triple-Resonance 1H-13C-15N backbone experiments
Triple-Resonance 1H-13C-15N sidechain experiments