Scully M F, Shah N, Ellis V, Kakkar V V
Thrombosis Research Institute, London, United Kingdom.
Thromb Haemost. 1991 Apr 8;65(4):351-4.
Chemical modification of tryptophan residues in antithrombin III by dimethyl (2-hydroxy-5-nitrobenzyl) sulfonium bromide (HNBSB) generates products with similar levels of modification (equivalent to 0.9 mole 2-hydroxy-5-nitrobenzyl [HNB] incorporated/mole of antithrombin III) but with high or low affinity for heparin-Sepharose. Upon digestion with pancreatic or neutrophil elastase the low affinity forms generate a product of molecular weight form (55 kDa) not seen in digests of native antithrombin III or modified forms with high affinity for heparin. When measured as loss of activity the observed rate of digestion of the latter in the absence of heparin was more rapid than that of native antithrombin III. The differences in digestion are considered to be related to conformation at differences between the various forms.
用二甲基（2-羟基-5-硝基苄基）溴化锍（HNBSB）对抗凝血酶III中的色氨酸残基进行化学修饰，生成的产物具有相似的修饰水平（相当于每摩尔抗凝血酶III掺入0.9摩尔2-羟基-5-硝基苄基[HNB]），但对肝素-琼脂糖具有高亲和力或低亲和力。在用胰蛋白酶或中性粒细胞弹性蛋白酶消化后，低亲和力形式产生一种分子量形式（55 kDa）的产物，这在天然抗凝血酶III或对肝素有高亲和力的修饰形式的消化产物中未见。当以活性丧失来衡量时，在无肝素情况下观察到的后者的消化速率比天然抗凝血酶III更快。消化的差异被认为与各种形式之间差异的构象有关。
