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

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 alpha-chymotrypsin were examined. Peptide (31-40) inhibited Cathepsin G (Ki = 2.3 x 10(-4) M), peptide (41-49) potently inhibited Cathepsin G and alpha-chymotrypsin (Ki = 4.2 x 10(-5) M and 2.0 x 10(-5) M, respectively), and peptide (60-63) inhibited leukocyte Elastase (Ki = 1.6 x 10(-4) M), whereas, peptide (31-35) weakly inhibited both Elastase and Cathepsin G (Ki = 2.1 x 10(-3) M and 7.3 x 10(-4) M, respectively).