AUTOPROTHROMBIN C: A SECOND ENZYME FROM PROTHROMBIN

1962 ◽  
Vol 40 (1) ◽  
pp. 597-605 ◽  
Author(s):  
Ewa Marciniak ◽  
Walter H. Seegers

In addition to thrombin, there is another derivative of prothrombin which is an end product of prothrombin activation. It is an accelerator of prothrombin activation, and is called autoprothrombin C. The activity develops from purified bovine prothrombin in 25% sodium citrate solution simultaneously with thrombin. It has been separated from thrombin by chromatography on Amberlite IRC-50 under the conditions previously used for the isolation of thrombin. The fraction which separates from thrombin has esterase activity and very likely this esterase activity is associated with the autoprothrombin C molecule. Since the autoprothrombin C and the thrombin are both derived from prothrombin, at least two enzymes are the end products of prothrombin activation. Autoprothrombin C catalyzed the activation of purified prothrombin in 25% sodium citrate solution, and this function was easily inhibited with p-toluenesulphonyl-L-arginine methyl ester. Autoprothrombin C preparations were mixed with platelets, Ac-globulin, and calcium ions to obtain rapid conversion of purified prothrombin to thrombin. This activation mixture did not generate autoprothrombin C and some unspecified substance most likely needs to be added in order to obtain the autoprothrombin C activity. The activity developed together with thrombin when tissue extracts, Ac-globulin, and calcium ions were used for the activation of prothrombin. Autoprothrombin C is relatively stable over the pH range 5.5 to 8.5. It is stable up to 56 °C for 30 minutes. Plasma contains a substance that inactivates autoprothrombin C.

1962 ◽  
Vol 40 (5) ◽  
pp. 597-605 ◽  
Author(s):  
Ewa Marciniak ◽  
Walter H. Seegers

In addition to thrombin, there is another derivative of prothrombin which is an end product of prothrombin activation. It is an accelerator of prothrombin activation, and is called autoprothrombin C. The activity develops from purified bovine prothrombin in 25% sodium citrate solution simultaneously with thrombin. It has been separated from thrombin by chromatography on Amberlite IRC-50 under the conditions previously used for the isolation of thrombin. The fraction which separates from thrombin has esterase activity and very likely this esterase activity is associated with the autoprothrombin C molecule. Since the autoprothrombin C and the thrombin are both derived from prothrombin, at least two enzymes are the end products of prothrombin activation. Autoprothrombin C catalyzed the activation of purified prothrombin in 25% sodium citrate solution, and this function was easily inhibited with p-toluenesulphonyl-L-arginine methyl ester. Autoprothrombin C preparations were mixed with platelets, Ac-globulin, and calcium ions to obtain rapid conversion of purified prothrombin to thrombin. This activation mixture did not generate autoprothrombin C and some unspecified substance most likely needs to be added in order to obtain the autoprothrombin C activity. The activity developed together with thrombin when tissue extracts, Ac-globulin, and calcium ions were used for the activation of prothrombin. Autoprothrombin C is relatively stable over the pH range 5.5 to 8.5. It is stable up to 56 °C for 30 minutes. Plasma contains a substance that inactivates autoprothrombin C.


1962 ◽  
Vol 203 (3) ◽  
pp. 397-400 ◽  
Author(s):  
Walter H. Seegers ◽  
Ewa Marciniak ◽  
Edmond R. Cole

Two enzymes, thrombin and autoprothrombin C, are derived from purified prothrombin by autocatalytic activation in 25% sodium citrate solution. The thrombin but not the autoprothrombin C activity is destroyed by diisopropylfluorophosphate. Autoprothrombin C is a procoagulant, which catalyzes the conversion of prothrombin to thrombin in a prothrombin-activating mixture consisting of calcium ions, Ac-globulin, and crude cephalin. Depending upon the amount of p-toluenesulphonyl-l-arginine methyl ester added to the prothrombin-activation mixture the thrombin generation may be retarded or inhibited completely. The view is expressed that all prothrombin activations are fundamentally autocatalytic. The end products of prothrombin activation involved are autoprothrombin C and thrombin, while the intermediate products of prothrombin activation are the autoprothrombins.


1964 ◽  
Vol 42 (2) ◽  
pp. 229-233 ◽  
Author(s):  
Walter H. Seegers ◽  
Edmond R. Cole ◽  
Nobuo Aoki ◽  
Charles R. Harmison

Purified prothrombin was activated by means of purified thrombin, Ac-globulin, calcium ions, and crude "cephalin." Thrombin and autoprothrombin III generated. The latter was isolated as a single component by the same methods found suitable for the isolation of autoprothrombin C. It contained no autoprothrombin C activity, but some generated spontaneously, and also in 25% sodium citrate solution. It may be that autoprothrombin C generally does not form in normal blood clotting unless tissue extracts are involved. This implies the possibility that the most potent procoagulant power in the genesis of thrombosis is derived from tissues.


1958 ◽  
Vol 193 (1) ◽  
pp. 169-180 ◽  
Author(s):  
Ricardo H. Landaburu ◽  
Walter H. Seegers

In experiments with purified biothrombin, it was found that strong solutions of sodium citrate or protamine sulfate (0.1% w/v) or purified platelet factor 3 depress the esterase activity and leave the clotting power unaltered. Apparently a depression of esterase activity is beneficial for the autocatalytic activation of purified prothrombin. In protamine sulfate solution, prothrombin gradually becomes thrombin and the yield of thrombin is even higher than in 25% sodium citrate solution. Prothrombin also depresses the esterase activity of biothrombin, and itself serves as a substrate for the enzyme thrombin. When prothrombin becomes an inactive derivative or a substance refractory to being converted to thrombin in the presence of Ac-globulin, thromboplastin and calcium ions, it can nevertheless be changed to thrombin with the use of thrombin as a catalyst, just as was previously accomplished with the use of 25% sodium citrate solutions. Theoretically, a prothrombin derivative(s) can serve as substrate competitor for thrombin and thus be an accelerator of prothrombin activation, or the derivative, under appropriate conditions can itself give rise to thrombin. Thrombin as activator of prothrombin can account for all observed conditions of prothrombin activation. The discovery of thrombin as activator of prothrombin offers a simplified view of the entire blood coagulation mechanisms. Two equations can describe the basic events: Prothrombin(See PDF for Equation)Thrombin; Fibrinogen(See PDF for Equation)Fibrin. Other factors support the production and enzymic function of thrombin and these are called procoagulants. Opposed to these, and normally in exact balance, are those factors that hinder the production or function of thrombin and these are called anticoagulants. In the presence of thrombin prothrombin can change to thrombin without Ac-globulin. Plasma Ac-globulin changes to serum Ac-globulin in the presence of thrombin but not with esterase thrombin. Consequently, the depression of esterase activity does not impair the capacity of thrombin to make the beneficial alteration in Ac-globulin.


1959 ◽  
Vol 37 (1) ◽  
pp. 775-785 ◽  
Author(s):  
Walter H. Seegers ◽  
Gerardo Casillas ◽  
Robert S. Shepard ◽  
William R. Thomas ◽  
Paul Halick

Bio-resin thrombin preparations were found to contain three weak precipitinogens. The clotting activity was not demonstrably associated with the precipitinogenic systems. Further, work was done on methods for the purification of citrate resin thrombin, and its clotting activity is also not associated with a precipitinogenic system. The N-terminal amino acid of both bio-resin thrombin and citrate resin thrombin was found to be glutamic acid. The two preparations were found to be homogeneous upon ultracentrifugal examination and could not be differentiated on the basis of sedimentation constants. Since "citrate" activation and "bio" activation produce eventually similar thrombin material, the autocatalytic activation of prothrombin in 25% sodium citrate solution can be used as an ideal model of prothrombin activation. The prothrombin first dissociates to form a derivative that does not form thrombin in the two-stage analytical reagents. Then a second alteration occurs in which the derivative again may form thrombin in the two-stage analytical reagents. Then thrombin activity appears as esterase activity, then as clotting activity. Later the clotting activity may be lost and finally also the esterase activity. The original prothrombin is a precipitinogen while the active thrombin is not.


1959 ◽  
Vol 37 (6) ◽  
pp. 775-785 ◽  
Author(s):  
Walter H. Seegers ◽  
Gerardo Casillas ◽  
Robert S. Shepard ◽  
William R. Thomas ◽  
Paul Halick

Bio-resin thrombin preparations were found to contain three weak precipitinogens. The clotting activity was not demonstrably associated with the precipitinogenic systems. Further, work was done on methods for the purification of citrate resin thrombin, and its clotting activity is also not associated with a precipitinogenic system. The N-terminal amino acid of both bio-resin thrombin and citrate resin thrombin was found to be glutamic acid. The two preparations were found to be homogeneous upon ultracentrifugal examination and could not be differentiated on the basis of sedimentation constants. Since "citrate" activation and "bio" activation produce eventually similar thrombin material, the autocatalytic activation of prothrombin in 25% sodium citrate solution can be used as an ideal model of prothrombin activation. The prothrombin first dissociates to form a derivative that does not form thrombin in the two-stage analytical reagents. Then a second alteration occurs in which the derivative again may form thrombin in the two-stage analytical reagents. Then thrombin activity appears as esterase activity, then as clotting activity. Later the clotting activity may be lost and finally also the esterase activity. The original prothrombin is a precipitinogen while the active thrombin is not.


1962 ◽  
Vol 08 (03) ◽  
pp. 425-433 ◽  
Author(s):  
Ewa Marciniak ◽  
Edmond R Cole ◽  
Walter H Seegers

SummarySuitable conditions were found for the generation of autoprothrombin C from purified prothrombin with the use of Russell’s viper venom or trypsin. DEAE chromatographed prothrombin is structurally altered and has never been found to yield autoprothrombin C and also did not yield it when Russell’s viper venom or trypsin were used. Autoprothrombin C is derived from prothrombin with tissue extract thromboplastin, but not in large amounts with the intrinsic clotting factors. With the latter thrombin and autoprothrombin III are the chief activation products. Autoprothrombin III concentrates were prepared from serum and upon activation with 25% sodium citrate solution or with Russell’s viper venom large amounts of autoprothrombin C were obtained, and this was of high specific activity. Theoretically trypsin is not a thrombolytic agent, but on the contrary should lead to intravascular clotting.


1959 ◽  
Vol 197 (6) ◽  
pp. 1178-1180 ◽  
Author(s):  
Ricardo H. Landaburu ◽  
Walter H. Seegers

In the activation of purified prothrombin with thrombin, with platelet factor 3, or in 25% sodium citrate solution the free thrombin activity which develops is greater at all times when measured by hydrolysis of p-toluenesulfonyl-arginine-methyl ester than when measured by the clotting of fibrinogen. Since the esterase activity appears before clotting power and remains after clotting power is lost, the clotting property must arise from a dissociable complex arising from the unit that has the esterase function. It is postulated that "clotting thrombin" may be a dimer of the lowest subunit of prothrombin required to have the proteolytic enzyme. The latter could have an important function in our physiology quite apart from the clotting of blood.


1968 ◽  
Vol 19 (01/02) ◽  
pp. 204-212 ◽  
Author(s):  
R Kipfer ◽  
W. H Seegers

SummaryAll reactions studied occurred in 25% sodium citrate solution. The conversion of prethrombin to thrombin with autoprothrombin C was retarded by 3,4,4’-triaminodi-phenyl sulfone. The compound functioned as a competitive inhibitor. Purified autoprothrombin III converted to autoprothrombin C more rapidly when autoprothrombin C was added at zero time. Soybean trypsin inhibitor, which neutralizes autopro-thrombin C activity, blocked the conversion of autoprothrombin III to autoprothrom-bin C, and 3,4,4’-triaminodiphenylsulf one inhibited the development of autoprothrombin C activity. The activation of prothrombin in 25% sodium citrate solution consists of three main events; namely, 1. the dissociation of prothrombin into subunits, 2. the formation of autoprothrombin C, and 3. the formation of thrombin.


1964 ◽  
Vol 42 (11) ◽  
pp. 1595-1603 ◽  
Author(s):  
Edmond R. Cole ◽  
J. L. Koppel ◽  
John H. Olwin

A thromboplastic enzyme, autoprothrombin C, can be complexed to different phospholipids and removed from solution in the form of such complexes. A technique for dissociating these complexes was developed, resulting in the recovery of the thromboplastic enzyme essentially free of phospholipid and in a higher degree of purity. Calcium ions are required for the formation of the complex, but strontium can replace calcium not only as the metal ion in the phospholipid-complexing system, but also as an autoprothrombin C cofactor in a prothrombin activation mixture. Magnesium was not effective in either system. The role of different phospholipids in the complexing phenomenon was studied and compared with the suitability of the same phospholipids as prothrombin-activating cofactors of autoprothrombin C. All phospholipid preparations studied complexed with autoprothrombin C to some degree, but the most efficient complexing agents were found to be asolectin and a commercial phosphatidyl ethanolamine preparation, both materials being among the ones which demonstrated the highest prothrombin conversion activity. Since thrombin was not complexed under the same conditions, autoprothrombin C could be isolated from commercial thrombin preparations also containing autoprothrombin C.


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