Cloning And Fusion Expression Of Predigested Human Plasminogen Kringle 5 In Escherichia Coli

Background & Objective Angiogenesis happens in many pathological processes, such as diabetic retinopathy, cardiovascular disorders, tumor growth, incursion, and metastasis. Briefly speaking, angiogenesis is regulated by both positive signals and negative signals. Among the reported endogenesis negative regulators , angiostatin is one of the most effective inhibitor, which is an internal fragment of plasminogen and consisted by the first four kringle domains of plasminogen. It has been documented that angiostatin could inhibit tumor growth effectively in vivo and in vitro. Further more, it was reported recently that the fifth kringle domain conjointed with angiostatin by a lysine was human plasminogen kringle 5(hPK-5), which had more potent ability of inhibition of migration of endothelial cells and neovascularization induced by growth factor and even inducement of apoptosis of some cancer cells. Study in molecular genetics shows that, these kringle domains display high structure similarity and about 50% sequence identity to each other. But their biological activity is different, intact kringle 1-3 has potent activity on inhibiting proliferation of endothelial cells,...