Tropomyosin (TM) extracted from pig cardiac muscle was spin-labeled with 2,2,6,6-tetramethyl-4-(dichlorotriazin)-aminopiperidine-1-oxyl. The ESR spectra of the product (SL-TM) were of a type of weak immobilization. Ef...Tropomyosin (TM) extracted from pig cardiac muscle was spin-labeled with 2,2,6,6-tetramethyl-4-(dichlorotriazin)-aminopiperidine-1-oxyl. The ESR spectra of the product (SL-TM) were of a type of weak immobilization. Effects of three means for the denaturation were observed on the above spectra. The ESR spectrum obtained for SL-TMafter enzymatic degradation was found to be analogous to that for the label itself in a dilute solution and thereby the quantity of labels bound in SL-TM estimated. The Arrhenius plots attained through variable temperature measurement for SL-TM’s exhibited two inflexion points (the conformational transition temperatures for TM) around 45℃ and 74-75℃, the latter temperature having not been reported in literature so far. However, the enzymatic degradation product from SL-TM behaved quite differently from it in the response to microwave power saturation and temperature variation.展开更多
基金Project supported by the National Natural Science Foundation of China
文摘Tropomyosin (TM) extracted from pig cardiac muscle was spin-labeled with 2,2,6,6-tetramethyl-4-(dichlorotriazin)-aminopiperidine-1-oxyl. The ESR spectra of the product (SL-TM) were of a type of weak immobilization. Effects of three means for the denaturation were observed on the above spectra. The ESR spectrum obtained for SL-TMafter enzymatic degradation was found to be analogous to that for the label itself in a dilute solution and thereby the quantity of labels bound in SL-TM estimated. The Arrhenius plots attained through variable temperature measurement for SL-TM’s exhibited two inflexion points (the conformational transition temperatures for TM) around 45℃ and 74-75℃, the latter temperature having not been reported in literature so far. However, the enzymatic degradation product from SL-TM behaved quite differently from it in the response to microwave power saturation and temperature variation.