A serine protease inhibitor from hemolymph of green mussel, Perna viridis

Bioactivity guided fractions of cell-free hemolymph of bacterially challenged marine mussel, Perna viridis led to the isolation of a novel quaternary alkaloid 1, which was identified by its spectral data. The isolated molecule 1 has been found to be a potent serine protease inhibitor (SPI) showing IC50 and Ki values of 102.5 and 97.1–104.68 μM, respectively. The Et/Ki value of SPI is 6.3, whereas Et/Km value is 1.04. The Van’t Hoff analysis showed that the value of Ki decreases with increase in temperature, and the binding of the inhibitor is entropically driven.

Figure optionsDownload as PowerPoint slide