Bangert K, Johnsen A H, Christensen U, Thorsen S
Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark.
Biochem J. 1993 Apr 15;291 ( Pt 2)(Pt 2):623-5. doi: 10.1042/bj2910623.
Mature alpha 2-plasmin inhibitor in human plasma has 12 more N-terminal residues than hitherto anticipated. The first residue is the methionine at position 28, downstream from the N-terminus of the pre-protein. The cDNA sequence predicts that the site cleaved upon formation of the mature inhibitor is a typical signal-peptidase recognition site. The mature inhibitor (464 residues) and the previously reported, and presumably degraded, form with N-terminal asparagine (452 residues), are present in plasma in about equal amounts. They both form a stable complex with plasmin. Recent studies on a recombinant alpha 2-plasmin inhibitor suggest that the 12 additional residues have functional implications [Sumi, Ichikawa, Nakamura, Miura and Aoki (1989) J. Biochem. 106, 703-707].
人血浆中的成熟α2-纤溶酶抑制剂比迄今预期的多12个N端残基。第一个残基是第28位的甲硫氨酸,位于前体蛋白N端下游。cDNA序列预测,成熟抑制剂形成时切割的位点是典型的信号肽酶识别位点。成熟抑制剂(464个残基)和先前报道的、可能已降解的N端天冬酰胺形式(452个残基)在血浆中的含量大致相等。它们都与纤溶酶形成稳定的复合物。最近对重组α2-纤溶酶抑制剂的研究表明,额外的12个残基具有功能意义[Sumi、Ichikawa、Nakamura、Miura和Aoki(1989年)《生物化学杂志》106,703 - 707]。