Isolation of HIV - 1 Protease Inhibiting Peptide from Thermolysin Hydrolysate of Manila Clam Proteins

A peptide inhibiting HIV-1 protease was isolated from the hydrolysate of manila clam (Ruditapes philippinarum) proteins digested with thermolysin. The peptide was purified by using membrane filtration, gel permeation chromatography, ion exchange chromatography, and reverse phase HPLC. The amino acid sequence of the peptide was determined to be Ile-Tyr-Glu-Gly. This tetrapeptide sequence exists in some proteins of Physarum polycephalum and Mycobacterium smegmatis. Chemically synthesized Ile-Tyr-Glu-Gly showed the IC_(50) value of 22.3 μM.