The solvent-exposed regions of [U-C-13]ascomycin when bound to its putative target protein, FKBP, have been identified based on the different proton longitudinal relaxation rates (R1 = 1/T1) measured in the absence and presence of the paramagnetic relaxation reagent, 4-hydroxy-2,2,6,6-tetramethyl-piperidinyl-1-oxy (HyTEMPO). The proton T1s of bound ascomycin were determined using a pulse sequence (T1-HMQC) which consists of a 180-degrees proton pulse and a variable delay (tau) followed by a heteronuclear multiple quantum correlation (HMQC) experiment. The solvent-exposed regions of ascomycin determined by these experiments are compared to NOE data in which ascomycin/FKBP contacts were identified and to the X-ray structure of the FK-506/FKBP complex.
Identification of Solvent-exposed Regions of An Fk-506 Analog, Ascomycin, Bound To Fkbp Using A Paramagnetic Probe
NERI, Placido;
1992-01-01
Abstract
The solvent-exposed regions of [U-C-13]ascomycin when bound to its putative target protein, FKBP, have been identified based on the different proton longitudinal relaxation rates (R1 = 1/T1) measured in the absence and presence of the paramagnetic relaxation reagent, 4-hydroxy-2,2,6,6-tetramethyl-piperidinyl-1-oxy (HyTEMPO). The proton T1s of bound ascomycin were determined using a pulse sequence (T1-HMQC) which consists of a 180-degrees proton pulse and a variable delay (tau) followed by a heteronuclear multiple quantum correlation (HMQC) experiment. The solvent-exposed regions of ascomycin determined by these experiments are compared to NOE data in which ascomycin/FKBP contacts were identified and to the X-ray structure of the FK-506/FKBP complex.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
