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
It is now well established that in vertebrate striated muscle there are two kinds of filaments, the thick filament and the thin filament. The evidence is strong that myosin is located in the former and actin in the la...It is now well established that in vertebrate striated muscle there are two kinds of filaments, the thick filament and the thin filament. The evidence is strong that myosin is located in the former and actin in the latter. By a direct isolation procedure we could also find tropomyosin in the thin filament. In the smooth molluscan adductor muscle, structural evidence has also been obtained for the presence of two kinds of filaments, but here the thick one is replaced by the very much thicker filament with characteristic 145 A cross-striations. The formal resemblance between the band patterns of this muscle and those of the crystal of para-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.
文摘It is now well established that in vertebrate striated muscle there are two kinds of filaments, the thick filament and the thin filament. The evidence is strong that myosin is located in the former and actin in the latter. By a direct isolation procedure we could also find tropomyosin in the thin filament. In the smooth molluscan adductor muscle, structural evidence has also been obtained for the presence of two kinds of filaments, but here the thick one is replaced by the very much thicker filament with characteristic 145 A cross-striations. The formal resemblance between the band patterns of this muscle and those of the crystal of para-
