【摘 要】
：
Aim: To study the enzymological characterization of a fibrinolytic enzyme (FⅡa)from Agkistrodon acutus venom. Methods: The fibrinogenolytic effect and the infl
【机 构】
：
Department of Pharmacology, Zhongshan Medical College, Sun Yat-Sen University, Guangzhou 510080, Chi
论文部分内容阅读
Aim: To study the enzymological characterization of a fibrinolytic enzyme (FⅡa)from Agkistrodon acutus venom. Methods: The fibrinogenolytic effect and the influences of several protease inhibitors, chelating agents, and metal ions on fibrinogenolytic activity were visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The metal content of FⅡa was determined by atomic absorption spectroscopy. Results: After incubation with EⅡa (0.25 g/L), Aα-, Bβ-and γ-chains of fibrinogen disappeared within 5 min, 30 min, and 8 h, respectively.The molecular weights of major degradation products were 45 000 and 41 000,which were different from those bands produced by plasmin. The fibrinogenolytic activity of FⅡa was strongly inhibited by ethylenediamine tetraacetic acid (EDTA),ethyleneglycol tetraacetic acid (EGTA), dithiothreitol and cysteine, but not by phenylmethyl-sulfonyl fluoride and soybean trypsin inhibitor. Zinc (3171±25mg/kg), potassium (489± 17 mg/kg) and calcium (319± 13 mg/kg) were found in FⅡa.Zn2+, Ca2+ and Mg2+ could recover the fibrinogenolytic activity of FⅡa, which was inhibited by EDTA. Only Ca2+ could recover the fibrinogenolytic activity inhibited by EGTA. Conclusion: FⅡa can degrade the Aα-, Bβ- and γ-chains of fibrinogen.EⅡa is a metalloproteinase, and Zn2+, Ca2+, and disulfide bonds are necessary for its fibrinogenolytic activity.
其他文献
1、应用近红外光谱技术分析稻米蛋白含量近红外光谱(near infrared renectance spectroscopy，NIRS)分析技术是20世纪80年代后期发展起来的，具有快速、无污染、样品不需预处理和同时检测多个组分等优点，目前已经在农作物品质育种、农牧产品质量分析、食品加工和品质检测等领域中广泛应用。本研究利用稻谷、米粒、米粉三种不同形态的样品，建立六个不同的近红外光谱模型，并对未知
卵泡刺激素受体(follicle stimulating hormone receptor,FSHR)被认为只表达在人和哺乳动物的睾丸支持细胞和卵巢颗粒细胞中,在生殖中具有重要作用。最近研究发现,FSHR在多种
“8·5”案件报道的事后,有一些同行曾询问我,有关这次事件采访报道的情况,想了解记者应当怎样进行突发性事件的报道?我想,总结这次采访实践,对自己是一次提高,同时,也是对
AIM: To explore the anti-diabetic effects of berberine and its influence on insulin secretion. METHODS: Impaired glucose tolerance rats induced by iv injection
Aim: N-methyl-D-aspartate receptors (NMDAR) are heteromeric complexes primarily assembled from NR1 and NR2 subunits. In normal conditions, NR2 sub-units assembl
本文研究了氮、钾水平及配比对晒红烟生理特性及化学成分的影响。结果表明：增施氮、钾肥能明显增加烟株的株高、有效叶片数、单株光合叶面积，施氮处理达到180kg／hm~2水平或施钾处理达到225kg／hm~2水平会产生抑制现象。叶质重在整个生育期内是不断增加的，调制以后叶质重下降到移栽后45d的水平，移栽45d以后，随氮、钾水平的提高叶质重下降；同一烟株不同部位烟叶的叶片厚度：上部叶＞中部叶＞下部叶，同
于2010年分三个航次对厦门湾海域海水水质状况进行调查,综合运用聚类分析、主成分分析等多元统计分析方法,对厦门湾海域水体污染的空间变异特征和污染来源进行分析,并提出了
本文以秋光和沈农265为试材，研究了水稻剑叶气孔密度、气孔长度与宽度、叶绿素含量、游离脯氨酸含量等性状在干旱胁迫、盐分胁迫以及盐分与干旱互作胁迫下相互关系及变化，探讨
AIM: To build a model of 3D-structure of H+, K+-ATPase catalytic subunit for theoretical study and anti-ulcer drug design. METHODS: The model was built on the b
本研究在对182份小麦亲本材料的农艺性状和HMW-GS构成进行鉴定筛选的基础上,选用综合农艺性状优良,且含有优质HMW-GS的4个亲本材料进行HMW-GS聚合杂交;采用在F_2分离世代进行HMW-GS标记辅助选择、重点筛选优质HMW-GS聚合体,在其后续世代重点进行产量相关性状鉴定的方法,进行了HMW-GS标记辅助选择优质小麦新品系的研究。主要研究结果如下:1.在分析182份小麦材料中,共检测到G