Pinpointing The Structural Dynamics of Plasminogen Activator Inhibitor 1 binding to Heparin using Hydrogen/Deuterium Exchange Mass Spectrometry

PAI-1 is a key player to regulate the activation of fibrinolysis, with broad influence effects on inflammation, hemostasis, tissue remodeling, and wound healing 1

The binding of endogenous cofactor vitronectin to PAI 1 helps to extend PAI 1 half life and delay its latency transition thus controlling the stability of the active form 1

Previous studies have suggested that low molecular weight heparin alters the levels of circulating PAI 1 and enhances endogenous fibrinolysis However, the intrinsic dynamics of this binding are not completely understood 2

Our findings reveal that Low Molecular Weight Heparin n ( may contribute to the localization of PAI 1 at specific sites, hence involved in the regulation of plasminogen activation and its functional stability

Hydrogen-Deuterium Exchange ( coupled to MS is widely used to study protein dynamics

Continuous time resolved Electrospray ionization TRESI HDX MS technique is used to characterize protein structural transitions in relatively ordered regions of proteins 3