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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 HNCACB experiment by typing rpar HNCACBGP3D all (the hncacbgp3d 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 37.36 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).
- Selective 90º 1H pulse on the water resonance via the observe f1 channel (p11 (about 2ms) at sp1 using spnam1=Sinc1.1000 and spoff1=0)
- Selective 90 13C pulses applied on-resonance on the aliphatic 13C 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).
- Selective 180 13C pulses applied on-resonance on the aliphatic 13C via the decoupler f2 channel (p14 (about 256u) at sp3, using spnam3=G3.256, spoff3=0).
- Selective 180 º 13C pulse applied off resonance on the CO resonances via the decoupler f2 channel (p14 (about 256u) at sp5, using spnam5=G3.256, spoff5=+120 ppm).
- Selective off-resonance CO decoupling via the decoupler f2 channel (pcpd2 at pl28=sp15 using cpdprg2=mlevsp180, spnam15=G3.256, and spoff15=+120ppm)
- 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 13C TD 2048 40 128 Spectral width NH (14.08 ppm) N (31.8 ppm) 13CA+13CB (75 ppm) Interpulse delays:
d22 is optimized to 1/(4*JN-CA) (12.4 ms)
d23 is optimized to 1/(4*JC-C) (3.5 ms)
d26 is optimized to 1/(4*JN-H) (2.3 ms)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=8 and ds=16) as a function of sample concentration. This experiment contains 3 gradients and the standard parameters are already defined with p16 of 1ms, d16=100u, gpnam1-3=sine.100 and the ratio is 30:80:8.1.
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 hncacb all command) to be used later.OTHER RELATED VERSIONS
Closely related pulse programs are also available:
- Gradient-Enhanced and 2H-decoupling (hncacbgp2h3d)
- Gradient-Enhanced using TROSY (trhncacbgp3d)
- Gradient-Enhanced and 2H-decoupling using TROSY (trhncacbgp2h3d)
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