Bendixen E, Harpel P C, Sottrup-Jensen L
Department of Molecular Biology, University of Aarhus, Denmark.
J Biol Chem. 1995 Jul 28;270(30):17929-33. doi: 10.1074/jbc.270.30.17929.
Tissue and plasma transglutaminases cross-link human plasminogen into high molecular weight complexes (Bendixen, E., Borth, W., and Harpel, P. C. (1993) J. Biol. Chem. 268, 21962-21967). A major cross-linking site in plasminogen involved in the tissue transglutaminase-mediated polymerization process has been identified. The epsilon-(gamma-glutamyl)lysyl bridges of the polymer are formed between Lys-298 and Gln-322. Both the acyl donor Gln residue and the acyl acceptor Lys residue are located in the kringle 3 domain of plasminogen, i.e. cross-linking of plasminogen by tissue transglutaminase involves neither the catalytic domain nor the lysine-dependent binding sites of plasminogen. This study documents that kringle 3 contains a novel functional site with the potential to participate in transglutaminase-mediated cross-linking interactions with plasma, cell-surface, and extracellular proteins.
组织型和血浆型转谷氨酰胺酶可将人纤溶酶原交联成高分子量复合物（本迪克森，E.，博尔特，W.，以及哈佩尔，P.C.（1993年）《生物化学杂志》268卷，21962 - 21967页）。已确定了纤溶酶原中参与组织型转谷氨酰胺酶介导的聚合过程的一个主要交联位点。聚合物的ε -（γ - 谷氨酰）赖氨酰桥在赖氨酸 - 298和谷氨酰胺 - 322之间形成。酰基供体谷氨酰胺残基和酰基受体赖氨酸残基均位于纤溶酶原的kringle 3结构域中，即组织型转谷氨酰胺酶对纤溶酶原的交联既不涉及纤溶酶原的催化结构域，也不涉及赖氨酸依赖性结合位点。本研究证明kringle 3含有一个新的功能位点，有可能参与转谷氨酰胺酶介导的与血浆、细胞表面及细胞外蛋白质的交联相互作用。
