Ishida Y, Takiuchi H, Matsushima A, Inada Y
Biochim Biophys Acta. 1978 Sep 26;536(1):70-7. doi: 10.1016/0005-2795(78)90052-1.
When human fibrinogen was modified with H2O2, inter- and intra-molecular cross-links of fibrinogen were formed, accompanied with oxidation of tryptophan, methionine and tyrosine residues. These cross-links may be closely associated with oxidation of tryptophan residues. The polymerization activity of fibrinogen with thrombin was decreased markedly by this modification. Modification of tryptophan residues in fibrinogen was also performed with 2-hydroxy-5-nitrobenzyl bromide. Modification of two out of a total 78 tryptophan residues in the molecule with the reagent led to the intensification (1.7 times) of the polymerization activity with thrombin and further modification of the next two residues led to complete loss of the polymerization activity. The first two tryptophan residues to be modified are in Fragment D, and the next two occur in Fragment E.
当人纤维蛋白原用H2O2修饰时，纤维蛋白原分子间和分子内形成交联，同时色氨酸、甲硫氨酸和酪氨酸残基发生氧化。这些交联可能与色氨酸残基的氧化密切相关。这种修饰显著降低了纤维蛋白原与凝血酶的聚合活性。还使用2-羟基-5-硝基苄基溴对纤维蛋白原中的色氨酸残基进行修饰。用该试剂修饰分子中总共78个色氨酸残基中的两个，导致与凝血酶的聚合活性增强（1.7倍），进一步修饰接下来的两个残基导致聚合活性完全丧失。最先被修饰的两个色氨酸残基在D片段中，接下来的两个在E片段中。
