ライフサイエンスコーパス: prothrombinase

1 nsible for the enhanced activation of FII by prothrombinase.

2 ry for efficient catalysis of prothrombin by prothrombinase.

3 ential role in its proteolytic activation by prothrombinase.

4 le for the enhanced procoagulant function of prothrombinase.

5 bin kinetics was determined predominantly by prothrombinase.

6 es the sequential cleavage of prothrombin by prothrombinase.

7 nt docking of Arg(271) at the active site of prothrombinase.

8 ding a recognition site for factor Va within prothrombinase.

9 a detectable way to the enhanced function of prothrombinase.

10 pending on the incorporation of factor Va in prothrombinase.

11 r Va molecule with the various components of prothrombinase.

12 he mechanism of activation of prothrombin by prothrombinase.

13 ffectively unaltered following assembly into prothrombinase.

14 cturally conserved residues in factor Xa and prothrombinase.

15 ane-bound procoagulant complexes, tenase and prothrombinase.

16 or V derivatives to assemble and function in prothrombinase.

17 one of two conformations to a single form of prothrombinase.

18 on of substrate derivatives and product with prothrombinase.

19 serine and inhibit the enzymatic activity of prothrombinase.

20 e of Oregon Green(488) at the active site of prothrombinase.

21 both possible intermediates, or product with prothrombinase.

22 s to bind in a mutually exclusive fashion to prothrombinase.

23 e with the incorporation of prothrombin into prothrombinase.

24 contribution of factor Va to the activity of prothrombinase.

25 nor does it fully explain the specificity of prothrombinase.

26 tor Xa or factor Xa saturably assembled into prothrombinase.

27 iants that could be converted to thrombin by prothrombinase.

28 eceding the scissile bond to the function of prothrombinase.

29 te-mediated protein substrate recognition by prothrombinase.

30 ulation zymogen not known to be activated by prothrombinase.

31 haBFX-2b bind in a mutually exclusive way to prothrombinase.

32 (AP4') was found to be a potent inhibitor of prothrombinase.

33 dent recognition of the protein substrate by prothrombinase.

34 oes not interfere with the assembly of human prothrombinase.

35 on of physiologically relevant inhibition of prothrombinase.

36 Va and/or prothrombin recognition by FXa in prothrombinase.

37 ability to accelerate thrombin production by prothrombinase.

38 rate at which it is converted to thrombin by prothrombinase.

39 on of the rate of cleavage of prothrombin by prothrombinase.

40 FII) is activated to alpha-thrombin (IIa) by prothrombinase.

41 for the strong procoagulant nature of venom prothrombinase.

42 s between the proteinase and cofactor within prothrombinase.

43 te of cleavage of prothrombin at Arg(271) by prothrombinase.

44 335) is required for the optimal activity of prothrombinase.

45 n the timely formation of alpha-thrombin via prothrombinase, a Ca(2+)-dependent complex of factors Va

46 ade, prothrombin is converted to thrombin by prothrombinase, a complex consisting of serine protease

47 Prothrombinase activates prothrombin through initial cle

48 se findings suggest that platelet-associated prothrombinase activates prothrombin via an efficient co

49 ested that although the peptide inhibits the prothrombinase activation of the wild type zymogen with

50 rmal affinities and exhibited wild-type-like prothrombinase activities toward prothrombin.

51 sistent with its activity, Alboserpin blocks prothrombinase activity and increases both prothrombin t

52 Peptide 325FIAAE329 inhibited prothrombinase activity and was able to partially decrea

53 Thus, RO318220 appears to increase prothrombinase activity by increasing platelet responsiv

54 re deficient in IQGAP1 demonstrate increased prothrombinase activity compared with wild-type litterma

55 Recent studies have found TFPI inhibits prothrombinase activity during the initiation of coagula

56 centration of 20 microM but had no effect on prothrombinase activity in the presence of excess factor

57 The exaggerated prothrombinase activity is not associated with enhanced

58 However, the prothrombinase activity of rHFVa W(2063, 2064)A was foun

59 tant factor Va are required for half-maximal prothrombinase activity on membranes containing 25% PS.

60 In addition, measurements of prothrombinase activity on the phospholipid bilayers sho

61 of factor Va (P15H) had no effect on either prothrombinase activity or the ability of the cofactor t

62 A mutant FXa (R165A) that has reduced prothrombinase activity showed both weakened dimerizatio

63 Even then, prothrombinase activity was low when compared with activ

64 Prothrombinase activity was tested on thrombin- and SFLL

65 252C) potently inhibited plasma clotting and prothrombinase activity with 50% inhibition between 41 a

66 N42R was found to inhibit prothrombinase activity with an IC50 of approximately 25

67 -704), were found to be potent inhibitors of prothrombinase activity with IC(50) values of approximat

68 I, induces platelet aggregation and platelet prothrombinase activity, and binds uniquely to GPVI in l

69 Both enhanced prothrombinase activity, and the increase was consistent

70 otently inhibited plasma clotting assays and prothrombinase activity, with 50% inhibition of 12 and 1

71 surface is necessary for the support of full prothrombinase activity.

72 of factor Xa were required for half-maximal prothrombinase activity.

73 ites per platelet, or the 3-fold increase in prothrombinase activity.

74 factor Va and tested them for inhibition of prothrombinase activity.

75 lets with exposed PS had greatly accelerated prothrombinase activity.

76 hosphatidylserine, and FV/Va expression; and prothrombinase activity.

77 n, and calcium ions, myosin greatly enhanced prothrombinase activity.

78 While the enzyme component of prothrombinase alone, factor Xa, bound to a membrane sur

79 n of prothrombin to thrombin is catalyzed by prothrombinase, an enzyme complex composed of the serine

80 ity binding and function of factor Xa within prothrombinase and 2) a binding site for prothrombin is

81 exosite-dependent tethering of substrate to prothrombinase and a relaxation in the constrained prese

82 Va heavy chain to factor Xa activity within prothrombinase and demonstrate that amino acid region 65

83 Both prothrombinase and direct binding studies indicated that

84 f factor Xa (FXa) with factor Va (FVa) forms prothrombinase and drives thrombin formation essential f

85 hat is modulated following its assembly into prothrombinase and in turn determines the binding specif

86 al cells can support formation of tenase and prothrombinase and may be a source of activated tissue f

87 Therefore, extended interactions between prothrombinase and substrate regions removed from the cl

88 s a prototypic exosite-directed inhibitor of prothrombinase and suggest that the occlusion of a surfa

89 actadherin was an efficient inhibitor of the prothrombinase and the factor Xase complexes regardless

90 ns and interactions with other components of prothrombinase, and (d) to use the model in order to und

91 x activates ProT with K(m)((app)) similar to prothrombinase, and approximately 85-fold weaker without

92 en activation when both extrinsic tenase and prothrombinase are assembled on an appropriate membrane.

93 es (exosites) rather than the active site of prothrombinase are the principal determinants of binding

94 itor of protein substrate cleavage by bovine prothrombinase as well.

95 croparticles were isolated and quantified by prothrombinase assay at admission, day 3, and day 7.

96 ibited a near normal affinity for fVa in the prothrombinase assay, but a markedly lower affinity for

97 atelet factor 3 availability assay and, in a prothrombinase assay, generated only background levels o

98 d neutrophil-derived CD66b microparticles by prothrombinase assay.

99 elet procoagulant activity was measured in a prothrombinase assay.

100 tent correlated positively with PS-direct in prothrombinase assays and clotting assays, but APC-cofac

101 sphatidylserine (PS), which was confirmed by prothrombinase assays and direct labeling.

102 hese adducts also promote the "PS-dependent" prothrombinase assays, albeit to lower levels.

103 on when Gla-domainless factor Xa was used in prothrombinase assays, whereas sphingosine inhibited act

104 I does not inhibit prothrombin activation by prothrombinase assembled on a two-dimensional lipid bila

105 Extension of these findings to the action of prothrombinase assembled on platelets and endothelial ce

106 Prothrombinase assembled on the surface of activated pla

107 a potent inhibitor of thrombin generation by prothrombinase assembled with C6PS, while TFPI-160 and K

108 ant molecules were impaired and the k cat of prothrombinase assembled with factor Va (KF) and factor

109 The second-order rate constant of prothrombinase assembled with factor Va (KF) or factor V

110 400-fold lower than the values obtained with prothrombinase assembled with factor Va (WT).

111 constant for the same reaction catalyzed by prothrombinase assembled with factor Va (WT).

112 n approximately 39% increase in k cat, while prothrombinase assembled with factor Va(4A) exhibited an

113 y employing purified reagents, we found that prothrombinase assembled with factor Va(Delta680-709) di

114 tivation compared to the value obtained with prothrombinase assembled with factor Va(Wt), while proth

115 the activation of prothrombin as compared to prothrombinase assembled with factor Va(Wt).

116 Prothrombinase assembled with factor VaFF/MI had decreas

117 The kcat value of prothrombinase assembled with fV(DeltaB9/Q3) was minimal

118 old compared with the Km value obtained with prothrombinase assembled with fVa(WT).

119 Prothrombinase assembled with saturating concentrations

120 ombinase assembled with factor Va(Wt), while prothrombinase assembled with saturating concentrations

121 Prothrombinase assembled with saturating concentrations

122 of plasma-derived prothrombin at Arg320 than prothrombinase assembled with saturating concentrations

123 for the overall activation of prothrombin by prothrombinase assembled with saturating concentrations

124 Kinetic analyses of prothrombinase assembled with the mutant molecules demon

125 phoresis analyzing prothrombin activation by prothrombinase assembled with the mutant molecules revea

126 prothrombin at both Arg(320) and Arg(271) by prothrombinase assembled with the mutant molecules, resu

127 Prothrombinase assembled with the quadruple mutant molec

128 via a concerted mechanism through a study of prothrombinase assembly and function on collagen-adhered

129 , HC1-HC5) and tested them for inhibition of prothrombinase assembly and function.

130 ssays, representing inhibition of productive prothrombinase assembly and possible disruption of FXa i

131 y the presumed preeminent role in supporting prothrombinase assembly and thrombin formation.

132 f phospholipid-associated factor Xa prior to prothrombinase assembly and/or by slowing formation of t

133 TFPI can also inhibit prothrombinase assembly by directly interacting with coa

134 Factor Va is the critical cofactor for prothrombinase assembly required for timely and efficien

135 Prothrombinase assembly was demonstrated through visuali

136 argets the early phase of coagulation before prothrombinase assembly.

137 in the regulation of exosite expression and prothrombinase assembly.

138 inhibits initial cleavage of prothrombin by prothrombinase at Arg(320).

139 sites to engage the active site of Xa within prothrombinase at equilibrium.

140 produced after activation of prothrombin by prothrombinase at the site of a vascular injury.

141 ctivation state was measured with a modified prothrombinase-based method.

142 al for coordinated prothrombin activation by prothrombinase because it regulates meizothrombin cleava

143 These data suggest that the peptides inhibit prothrombinase because they interfere with the incorpora

144 the affinity of the wild type substrate for prothrombinase but did not engage the active site of the

145 n (DYDYQ) inhibits prothrombin activation by prothrombinase by inhibiting meizothrombin generation.

146 Similar analyses of the inhibition of human prothrombinase by PD0313052 also identified a slow-onset

147 Inhibition of prothrombinase by PT557-571 and X415-429 was fVa-indepen

148 We demonstrate rapid inhibition of prothrombinase by TFPIalpha mediated through a high-affi

149 e individual cleavage reactions catalyzed by prothrombinase by using a series of recombinant derivati

150 us, the observed pathway of bond cleavage by prothrombinase can be explained by the kinetic constants

151 er, mutation of Arg(320) to Gln reveals that prothrombinase can cleave prothrombin following Arg side

152 r Va (FVa) serve essential cofactor roles in prothrombinase-catalyzed thrombin generation.

153 Prothrombinase catalyzes thrombin formation by the order

154 n activated platelets with factor Va to form prothrombinase completely restores biologic activity.

155 antithrombin inhibition of factor Xa in the prothrombinase complex (factor Va, negatively charged me

156 tivation of prothrombin, as catalyzed by the prothrombinase complex (factor X(a), enzyme; factor V(a)

157 prothrombin recognition by factor Xa in the prothrombinase complex (factor Xa, factor Va, phosphatid

158 The central findings are as follows: 1) the prothrombinase complex (fVa-fXa-Ca(2+)-membrane) accumul

159 nd prothrombin (fII) that may be involved in prothrombinase complex (fXa.factor Va.fII.phospholipids)

160 y sequences in prothrombin (fII) involved in prothrombinase complex (fXa.fVa.fII.phospholipids) assem

161 Thrombin generation assays measuring prothrombinase complex activity demonstrated 1.5-fold hi

162 vivo is the activation of prothrombin by the prothrombinase complex assembled on either an activated

163 The prothrombinase complex assembled on the surface of plate

164 323-331 and tested them for their effect on prothrombinase complex assembly and function.

165 iding the necessary procoagulant surface for prothrombinase complex assembly and thrombin generation.

166 PS, with binding to the C1 domain regulating prothrombinase complex assembly.

167 nes support formation of a 60-70% functional prothrombinase complex at saturating factor Va concentra

168 = approximately 40 nm) of a partially active prothrombinase complex between factor Xa and factor Va(2

169 Based on inhibition of the prothrombinase complex by synthetic peptides, FVa residu

170 The prothrombinase complex catalyzes the activation of proth

171 thrombin is proteolytically activated by the prothrombinase complex comprising the serine protease Fa

172 The prothrombinase complex consists of the protease factor X

173 The fully formed prothrombinase complex containing this FVa mutant had fa

174 The prothrombinase complex converts prothrombin to alpha-thr

175 a, either in free form or assembled into the prothrombinase complex during the process of prothrombin

176 m spontaneous binding to fXa and unnecessary prothrombinase complex formation, which in turn results

177 avage of prothrombin (ProT) at Arg320 by the prothrombinase complex generates proteolytically active,

178 ts to determine the crystal structure of the prothrombinase complex have been thwarted by the depende

179 and that a cofactor function for fVa in the prothrombinase complex involves inducing a conformationa

180 enzyme activated factor X (FXa) to form the prothrombinase complex is a pivotal initial event in blo

181 The prothrombinase complex is comprised of an enzyme, factor

182 ht heparins, indicates that factor Xa in the prothrombinase complex is protected from inhibition by a

183 undation for the establishment of a complete prothrombinase complex model, which might be successful

184 rsion of fII to alpha-thrombin (fIIa) by the prothrombinase complex occurs through 2 parallel pathway

185 pt that protein substrate recognition by the prothrombinase complex of coagulation is achieved by int

186 In the prothrombinase complex on the platelet surface, FXa clea

187 blocking phospholipid binding sites for the prothrombinase complex on the surfaces of vesicles and a

188 Pseutarin C is an intrinsically stable prothrombinase complex preassembled in the venom gland o

189 Further studies with the wild-type prothrombinase complex revealed that FXa binds to factor

190 soluble PS to trigger formation of a soluble prothrombinase complex suggests that exposure of PS mole

191 sis, factor Va serves as the cofactor in the prothrombinase complex that results in a 300,000-fold in

192 espect to their ability to assemble into the prothrombinase complex to activate prothrombin and inter

193 ns prothrombin and prethrombin-2 require the prothrombinase complex to be converted to the mature pro

194 lex and then to function as an enzyme in the prothrombinase complex to catalyze the conversion of pro

195 ant substrates; however, its activity in the prothrombinase complex toward most of mutants was severe

196 e-exposed phosphatidylserine (PS) forms the "prothrombinase complex" that is essential for efficient

197 ctly inhibits thrombin generated by FXa/FVa (prothrombinase complex).

198 ng tissue factor VIIa activity, Xa activity, prothrombinase complex, and thrombin generation.

199 The prothrombinase complex, composed of the protease factor

200 ts or endothelial cells, factor Xa forms the prothrombinase complex, which is responsible for the pro

201 d Partial Thromboplastin Time'' (aPTT) and ''Prothrombinase complex-induced Clotting Test'' (PiCT) ha

202 t into the architecture and mechanism of the prothrombinase complex-the molecular engine of blood coa

203 ed as an extended FXa binding surface in the prothrombinase complex.

204 ependent prothrombin recognition site in the prothrombinase complex.

205 rsor prothrombin by factor Xa as part of the prothrombinase complex.

206 oth FIXa in the FXase complex and FXa in the prothrombinase complex.

207 ely 3-fold lower catalytic efficiency in the prothrombinase complex.

208 le in FXa recognition of the cofactor in the prothrombinase complex.

209 phatidylserine (PS) regulate activity of the prothrombinase complex.

210 or Va and the Gla domain of factor Xa in the prothrombinase complex.

211 iate interactions between fVa and fII in the prothrombinase complex.

212 ndent recognition sites for factor Xa in the prothrombinase complex.

213 iate interactions between fXa and fII in the prothrombinase complex.

214 ction as zymogens for both factor Xa and the prothrombinase complex.

215 assembly and/or by slowing formation of the prothrombinase complex.

216 e protein substrate recognition by the human prothrombinase complex.

217 and phospholipid membranes, and inhibit the prothrombinase complex.

218 telet membranes regulate the activity of the prothrombinase complex.

219 sequential cleavages at R271 and R320 by the prothrombinase complex.

220 dent recognition site for prothrombin in the prothrombinase complex; however, Lys-96 is a recognition

221 ufficient to produce the fully active human "prothrombinase" complex in solution.

222 ng platelet membranes to form the essential "prothrombinase" complex of blood coagulation.

223 f prothrombin to thrombin is catalyzed by a "prothrombinase" complex, traditionally viewed as factor

224 common" pathway at the level of the FXa/FVa (prothrombinase) complex.

225 ide a surface for assembly of the tenase and prothrombinase complexes required for thrombin generatio

226 egulator of both the intrinsic FXase and the prothrombinase complexes.

227 Prothrombinase converts prothrombin to thrombin via clea

228 cket indicate that assembly of the mutant in prothrombinase corrected the impaired binding of these p

229 lpha produces isoform-specific inhibition of prothrombinase during the initiation of coagulation, an

230 r interactions that underlie the assembly of prothrombinase, efficient inhibition of enzyme complex a

231 n of factor Xa was not required for myosin's prothrombinase enhancement.

232 Exosite-dependent binding of prothrombin to prothrombinase facilitates active site docking by Arg(32

233 intrinsic tenase (factor VIIIa/factor IXa), prothrombinase (factor Va/factor Xa), and factor XIa com

234 Because all three protein components of prothrombinase, factors (f) Xa and Va and prothrombin, b

235 irudin, or CD39, or lacking the gene for the prothrombinase, fibrinogen-like protein-2, is anticipate

236 ation expresses phosphatidylserine and binds prothrombinase (FITC Xa.factor Va).

237 milieu already containing factor Xa enables prothrombinase formation with consequent meizothrombin f

238 cells, whereas TFPIalpha dampens the initial prothrombinase formed on the activated platelet surface.

239 ntapeptide with this sequence inhibited both prothrombinase function with an IC(50) of 1.6 microm (wi

240 de the primary biological surface to support prothrombinase function.

241 actor activation and is required for optimum prothrombinase function.

242 exclusive manner and with equal affinity to prothrombinase in a cleavage site-independent way.

243 n, DYDYQ) inhibits prothrombin activation by prothrombinase in a competitive manner with respect to s

244 (2K2F) had impaired cofactor activity within prothrombinase in a system using purified reagents.

245 teolyzed prothrombin species by preassembled prothrombinase in phospholipid-coated glass capillaries

246 ation of the incorporation of factor Va into prothrombinase in vivo by using synthetic peptides that

247 A direct prothrombinase inhibition assay, monitoring thrombin gen

248 Prothrombinase inhibition by PT473-487 was factor Va (fV

249 the properties of a unique exosite-directed prothrombinase inhibitor.

250 s thrombin is known to bind to an exosite on prothrombinase, initial interactions at an exosite likel

251 ferred pathway for prothrombin activation by prothrombinase involves initial cleavage at Arg(320) to

252 When prothrombinase is assembled on synthetic phospholipid ve

253 tivation of prothrombin by surface-localized prothrombinase is clearly mediated by flow-induced dilut

254 Prothrombinase is composed of a catalytic subunit, facto

255 The ordered cleavage of prothrombin by prothrombinase is driven by ratcheting of the substrate

256 Tris(+) and that the catalytic efficiency of prothrombinase is enhanced less than 1.5-fold by the spe

257 ontributes to enhanced catalytic efficacy of prothrombinase is not precisely known but is generally a

258 n of all three possible substrate species by prothrombinase is regulated by their ability to bind mem

259 Factor Va, the cofactor of prothrombinase, is composed of heavy and light chains as

260 ce this modified derivative was assembled in prothrombinase, it functioned in an equivalent manner to

261 hrombin 2 or meizothrombin des-fragment 1 by prothrombinase (K(i)(*) = 0.55 +/- 0.05 nm).

262 complexes of the intrinsic pathway, Xase and prothrombinase, leading to a 20- and 10-fold increase in

263 r rate over preassembled platelet-associated prothrombinase neither potential intermediate, meizothro

264 ation constant (Kd,app) for factor Xa within prothrombinase of approximately 0.5 nM.

265 e for cleavage, yet the sequential action of prothrombinase on Arg(320) followed by Arg(271) is impli

266 of the fVa-dependent site(s) for fXa within prothrombinase on FII, required for efficient initial cl

267 We have examined the action of prothrombinase on full-length prothrombin variants lacki

268 specificity as well as the ordered action of prothrombinase on its compound substrate is regulated by

269 hrombin is produced by the ordered action of prothrombinase on two cleavage sites in prothrombin.

270 te directed inhibitor of human factor Xa and prothrombinase, PD0313052, and identifies structurally c

271 The enzyme complex prothrombinase plays a pivotal role in fibrin clot devel

272 ork tests whether or not platelet-associated prothrombinase proceeds via a concerted mechanism throug

273 These results suggest that, similar to prothrombinase, proexosite-1 is a cofactor-dependent rec

274 actor Xa with factor Va on membranes to form prothrombinase profoundly increases the rate of the prot

275 rate of 83.9 +/- 3.8 nM/min by about 120 pM prothrombinase, reaching ultimate levels of 851 +/- 53 n

276 ipids, the exact role of the membrane in the prothrombinase reaction has not been fully understood.

277 n are part of a cooperative mechanism within prothrombinase regulating cleavage and activation of pro

278 on of the cofactor molecule, factor Va, into prothrombinase results in a five orders of magnitude inc

279 hus, alphaBFX-2b binding to factor Xa within prothrombinase selectively leads to the inhibition of pr

280 To determine whether, similar to prothrombinase, taipan venom utilizes proexosite-1 on pr

281 Furthermore, activation by prothrombinase takes place without preference along the

282 actor Xa is the serine protease component of prothrombinase, the enzymatic complex responsible for th

283 vents prothrombin autoactivation and directs prothrombinase to cleave at Arg-271 first.

284 local electrostatic potential then redirects prothrombinase toward Arg-320, leading to thrombin gener

285 Cleavage of rMZ-II by prothrombinase was completely inhibited by low concentra

286 her structural determinants in factor Xa and prothrombinase was investigated.

287 (S195A), the pathway of FPR-ProT cleavage by prothrombinase was redirected from meizothrombin toward

288 n with the factor Xa variants assembled into prothrombinase was unaltered, whereas the k(cat) was mod

289 In rapid kinetic measurements with prothrombinase, we also show that the zymogen-like form

290 meizothrombin des fragment 1 and thrombin to prothrombinase were comparable with their affinities inf

291 factor Va governing its incorporation within prothrombinase will provide the scaffold for the synthes

292 actor Va binding to any of the components of prothrombinase, will allow for control of the rate of th

293 at HC3 and HC4 are competitive inhibitors of prothrombinase with respect to prothrombin with K(i) val

294 d that AP4' is a noncompetitive inhibitor of prothrombinase with respect to prothrombin, with a K(i)

295 ) was found to be a competitive inhibitor of prothrombinase with respect to prothrombin.

296 trate cleavage by human Xa incorporated into prothrombinase with saturating concentrations of membran

297 of plasma-derived prothrombin activation by prothrombinase, with increasing concentrations of peptid

298 fVa-dependent recognition exosite for fXa in prothrombinase within the amino acid sequence Ser(478)-V

299 7t) inhibits thrombin formation catalyzed by prothrombinase without obscuring the active site of Xa w

300 .93 +/- 0.3 nM/min catalyzed by about 1.3 pM prothrombinase yielding approximately 26 nM thrombin.