NMR relaxation by intermolecular and intramolecular dipolar interactions in small molecules round to an enzyme

摘要: Abstract NMR relaxation times T1 and T2 their temperature dependence were measured for sulfonamide inhibitors acetate ion specifically bound to bovine carbonic anhydrase. Frequency of indicated a dipolar mechanism rather than chemical shift dependent mechanism. Both T 1 2 ratios frequency dependences that the tumbling correlation time aromatic ring protons is similar whole protein with no independent motion. Moreover, it was concluded major part interaction due an intermolecular protons. Methyl groups found have faster This motion discussed in terms Woessner's theory [J. Chem. Phys.36, (1962)]. The methyl N1-acetylsulfanilamide isotropic random protein. group p-toluenesulfonamide undergo anisotropic composed fast rotation about threefold axis slower this together