Substrate specificity of tissue plasminogen activator and urokinase as determined with synthetic chromogenic substrates.

Publisher Website
Google Scholar
Abstract
Three different synthetic chromogenic substrates (H-glutamyl-glycyl-L-arginine-p-nitroanilide (S-222], pyro-glutamyl-glycyl-D-arginine-p-nitroanilide (S-2444) and H-D-isoleucyl-L-prolyl-L-arginine-p-nitroanilide (S-2288)) were investigated for use in the measurement of [human] plasminogen activator activity with high MW urokinase (H-UK), low MW urokinase (L-UK) and tissue plasminogen activator (TPA). The 3 substrates were hydrolyzed by both TPA-type and UK-type plasminogen activator. As regards the amidolytic activity of S-2227, TPA exhibited a weaker amidolyic activity and L-UK a stronger activity. In the case of the amidolytic activity of S-2444, no great difference between the 3 activators was observed in terms of Vmax. As regards the amidolytic activity of S-2288, L-UK exhibited a stronger activity and TPA a weaker activity. Perhaps, the molecular size of the synthetic chromogenic substrate was too small when compared to natural substrate (fibrin), and therefore fibrin-binding sites around the catalytic site in TPA are not recognized.

This publication has 0 references indexed in Scilit: