A novel variant fibrinogen, AαE11del, demonstrating the important of AαE11 residue in thrombin binding
A novel variant fibrinogen, AαE11del, demonstrating the important of AαE11 residue in thrombin binding
复制标题
一种新型变异纤维蛋白原 AαE11del，证明了 AαE11 残基在凝血酶结合中的重要性
DOI：
10.1007/s12185-021-03200-z
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Okumura N
中科院分区：
文献类型：
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作者：
Kaido T;Yoda M;Kamijo T;Arai S;Yamauchi K;Okumura N
简介我们在一名先天性纤维蛋白原异常血症患者中发现了一种新型杂合 AαE11del 变异。该突变位于纤维蛋白肽 A (FpA) 中。我们分析了AαE11del对凝血酶和巴曲酶催化的影响，并模拟了FpA片段（AαG6-V20）肽和凝血酶之间的复合结构的稳定性。材料和方法我们使用纯化的血浆纤维蛋白原进行纤维蛋白聚合，并检查了凝血酶和巴曲酶催化的FpA释放动力学。为了阐明 AαE11 残基和凝血酶之间的关联，我们使用分子动力学模拟轨迹计算了结合自由能。结果增加凝血酶浓度，患者纤维蛋白原中 FpA 的释放量提高到约 90%，而之前正常纤维蛋白原的释放量为 50%。变异纤维蛋白原的纤维蛋白聚合也得到改善。此外，与巴曲酶相比，凝血酶对患者纤维蛋白原中变体 FpA 释放的损害更大。此外，计算的结合自由能表明，由于缺少 AαE11 残基，FpA 片段-凝血酶复合物变得不稳定。结论我们的研究结果表明，与巴曲酶催化相比，AαE11 残基更多地参与凝血酶催化中的 FpA 释放，并且 AαE11 残基稳定了 FpA 片段-凝血酶复合物的形成。
IntroductionWe identified a novel heterozygous AαE11del variant in a patient with congenital dysfibrinogenemia. This mutation is located in fibrinopeptide A (FpA). We analyzed the effect of AαE11del on the catalyzation of thrombin and batroxobin and simulated the stability of the complex structure between the FpA fragment (AαG6-V20) peptide and thrombin.Materials and methodsWe performed fibrin polymerization and examined the kinetics of FpA release catalyzed by thrombin and batroxobin using purified plasma fibrinogen. To clarify the association between the AαE11 residue and thrombin, we calculated binding free energy using molecular dynamics simulation trajectories.ResultsIncreasing the thrombin concentration improved release of FpA from the patient’s fibrinogen to approximately 90%, compared to the previous 50% of that of normal fibrinogen. Fibrin polymerization of variant fibrinogen also improved. In addition, greater impairment of variant FpA release from the patient’s fibrinogen was observed with thrombin than with batroxobin. Moreover, the calculated binding free energy showed that the FpA fragment–thrombin complex became unstable due to the missing AαE11 residue.ConclusionsOur findings indicate that the AαE11 residue is involved in FpA release in thrombin catalyzation more than in batroxobin catalyzation, and that the AαE11 residue stabilizes FpA fragment–thrombin complex formation.