Analysis of the interaction between α2-antiplasmin and plasmin(ogen) LuBernadine Gueh Cheng 2017 Plasminogen is a multi-domain molecule which consists of a pan-apple domain, five kringles and a serine protease domain. Activation of plasminogen to plasmin converts the zymogen to a potent enzyme which dissolves blood clots. α2-antiplasmin is the physiological inhibitor of plasmin. In addition to the conserved serpin core, α2-antiplasmin also possesses two unique N- and C-terminal extensions. The conserved lysine residues (Lys427, Lys434, Lys441, Lys448 and Lys464) in the C-terminus are essential in mediating binding with plasmin kringle domains. Disrupting the interaction of the C-terminus to plasmin has been shown to decrease plasmin inhibition resulting in increased fibrinolysis. To better understand the interaction that occurs between α2-antiplasmin and plasmin, this thesis explored the basic biochemical and binding properties of these multi-domain molecules.