A novel composite 90 degrees pulse sequence which provides distortionless NMR spectra and suppresses without destroying the water magnetization.
A novel 90 degrees composite pulse sequence which allows one to record 1D and 2D NMR spectra without disturbing the water magnetization is described. A home-written program was used to optimize the pulse angles for which the pulse sequence response fitted best the desired excitation profile, producing a neat and distortionless spectrum with a broad null excitation at the carrier frequency. The resulting pulse sequence was first evaluated using the simulation program "PENCIL" and then tested on two protein samples. A 3.5 degrees phase shift of the last pulse was required to cancel correctly the water signal. The pulse scheme was appended to a NOESY pulse sequence. Inspection of the water cross section revealed interactions between water and some protons of drosomycine, a small insect antifungal protein.
Sodano
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Centre de Biophysique Moléculaire, CNRS-UPR 4301 conventionnéavec l'Universitéd'Orléans, rue Charles Sadron, Orléans Cedex 02, 45071, France.
Landon
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C
Ptak
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M
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D000935:Antifungal Agents / Q000032:analysis; D052179:Antigens, Plant; D002352:Carrier Proteins / Q000032:analysis; D003198:Computer Simulation; D029721:Drosophila Proteins; D007089:Image Enhancement / Q000379:methods; D019476:Insect Proteins / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008280:Magnetics; D010940:Plant Proteins; D011522:Protons; D012984:Software; D014908:Triticum; D014867:Water / Q000737:chemistry
D000596:Amino Acids; D000935:Antifungal Agents; D052179:Antigens, Plant; D002352:Carrier Proteins; D029721:Drosophila Proteins; D019476:Insect Proteins; D010940:Plant Proteins; D011522:Protons; C511920:lipid transfer proteins, plant; D014867:Water; C091227:DRS protein, Drosophila