Amino Acids and Peptides. XXXVII. Synthesis of Stereoisomeric Nonapeptides Corresponding to Sequence 41-49 of Eglin c and Examination of Their Inhibitory Activity against Human Leukocyte Cathepsin G and .ALPHA.-Chymotrypsin.
作者:Ayumi FUJII、Satoshi TSUBOI、Keiichi ASADA、Yoko NAGAMATSU、Junichiro YAMAMOTO、Yoshio OKADA
DOI:10.1248/cpb.42.1518
日期:——
A nonapeptide, H-Ser-Pro-Val-Thr-Leu-Asp-Leu-Arg-Tyr-OH, corresponding to sequence 41-49 of eglin c inhibited leukocyte cathepsin G and α-chymotrypsin with Ki values of 2.2×10-5 and 7.2×10-6M, respectively, although eglin c itself inhibited leukocyte elastase, cathepsin G and α-chymotrypsin with Ki values of 6.0×10-9, 5.5×10-9 and 2.5×10-9M, respectively. The inhibitory activity of the nonapeptide decreased following incubation with cathepsin G due to the cleavage of the Leu45-Asp46 peptide bond. Therefore, Leu45 and/or Asp46 were replaced with D-amino acids and the inhibitory activities of the resultant nonapeptides were examined. Their inhibitory activities against cathepsin G and α-chymotrypsin were much weaker than those of the all-L-type nonapeptide, suggesting that the amino acids at the active site, Leu45 and Asp46 are required to be in the L-configuration for potent activity.
一种非apeptide,H-Ser-Pro-Val-Thr-Leu-Asp-Leu-Arg-Tyr-OH,对应于eglin c序列41-49,分别以2.2×10-5和7.2×10-6M的Ki值抑制白细胞组织蛋白酶G和α-胰凝乳蛋白酶,尽管eglin c本身分别以6.0×10-9、5.5×10-9和2.5×10-9M的Ki值抑制白细胞弹性蛋白酶、组织蛋白酶G和α-胰凝乳蛋白酶。非apeptide的抑制活性在与组织蛋白酶G孵育后下降,这是由于Leu45-Asp46肽键的断裂。因此,Leu45和/或Asp46被替换为D-氨基酸,并对产生的非apeptide的抑制活性进行了检查。它们对组织蛋白酶G和α-胰凝乳蛋白酶的抑制活性远弱于所有L型非apeptide,表明活性位点上的氨基酸,Leu45和Asp46,需要处于L-构型才能发挥强大活性。