Enhancement of Reciprocal Activation of Prourokinase and Plasminogen by the Bacterial Lipopeptide Surfactins and Iturin Cs.

Urokinase-type plasminogen activator (u-PA) is a serine protease that cleaves Arg561-Val562 bond in plasminogen to convert it to the active serine protease plasmin, which is involved not only in blood clot dissolution but also in a variety of physiological and pathological processes requiring localized proteolysis1). u-PA is synthesized and secreted as a single-chain zymogen form (pro-u-PA)2). Prou-PA is proteolytically activated (by cleavage at Lys158-Ile159) into a two-chain form (tcu-PA) by plasmin2,3). It is