Identification of a new exosite involved in catalytic turnover by the streptokinase-plasmin activator complex during human plasminogen activation.

ABSTRACT: With the goal of identifying hitherto unknown surface exosites of streptokinase involved in substrate human plasminogen recognition and catalytic turnover, synthetic peptides encompassing the 170 loop (CQFTPLNPDDDFRPGLKDTKLLC) in the beta-domain were tested for selective inhibition of substrate human plasminogen activation by the streptokinase-plasmin activator complex. Although a disulfide-constrained peptide exhibited strong inhibition, a linear peptide with the same sequence, or a disulfide-constrained variant with a single lysine to alanine mutation showed significantly reduced capabilities of inhibition. Alanine-scanning mutagenesis of the 170 loop of the beta-domain of streptokinase was then performed to elucidate its importance in streptokinase-mediated plasminogen activation. Some

SUBMITTER: Aneja R 

PROVIDER: S-EPMC2781679 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature