Synthesis of peptide fragments related to eglin c and examination of their inhibitory effect on human leukocyte elastase, cathepsin G and α-chymotrypsin

Abstract Various kinds of peptide fragments related to eglin c were prepared by the conventional solution method and their inhibitory effects on human leukocyte elastase, cathepsin G and α-chymotrypsin were examined. Peptide (31–40) inhibited cathepsin G (Ki=2.3×10 −4 M), peptide (41–49) potently inhibited cathepsin G and α-chymotrypsin (Ki=4.2×10 −5 M and 2.0×10 −5 M, respectively), and peptide (60–63) inhibited leukocyte elastase (Ki=1.6×10 −4 M), whereas, peptide (31–35) weakly inhibited both elastase and cathepsin G (Ki=2.1×10 −3 M and 7.3×10 −4 M, respectively).