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Cyclic analogues of wasp kinins from Vespa analis and Vespa tropica

1995; Wiley; Volume: 45; Issue: 3 Linguagem: Inglês

10.1111/j.1399-3011.1995.tb01490.x

0367-8377

Marina Gobbo, Laura Biondi, Fernando Filira, Raniero Rocchi, T. Piek,

Protein Hydrolysis and Bioactive Peptides

Syntheses are described of two bradykinin‐like kinins isolated from Vespa analis (G‐R‐P‐P‐G‐F‐S‐P‐F‐R‐V‐I, VSK‐A) and Vespa tropica (G‐R‐P‐Hyp‐G‐F‐S‐P‐F‐R‐V‐V, VSK‐T) and of their cyclic analogues. Linear dodecapeptides were prepared by the solid‐phase procedure based on Fmoc‐chemistry, and cyclization was carried out by the diphenyl‐phosphorazide method. Peptides were characterized by amino acid analysis, optical rotation, analytical HPLC and FAB‐MS. The conformational features of the cyclic and linear kinins were determined by circular dichroism measurements in water, 95% trifluoroethanol and 8 M guanidinium chloride. Consistent with previous findings, preliminary pharmacological experiments on smooth muscle preparations showed that cyclic wasp kinins were 50–100 times less potent than their linear analogues. Moreover, cyclo‐VSK‐A and cyclo‐VSK‐T behave like kininase inhibitors by preventing the degradation of straight kinins.