Isolation: Analysis and Properties of Three Bradykinin–Potentiating Peptides (BPP-II, BPP-III, and BPP-V) From Bothrops Neuwiedi Venom

Abstract

In the course of systematic investigations on low-molecular-weight compounds from the venom of Crotalidae and Viperidae, we have isolated and characterized at least three bradykinin-potentiating peptides (BPP-II, BPP-III, and BPP-V) from Bothrops neuwiedi venom by gel filtration on Sephadex G-25 M, Sephadex G-10 followed by HPLC. The peptides showed bradykinin-potentiating action on isolated guinea-pig ileum, for which the BPP-V was more active than of BPP-II, and BPP-III, rat arterial blood pressure, and a relevant angiotensin-converting enzyme (ACE) competitive inhibiting activity. The kinetic studies showed a K _i of the order of 9.7 × 10⁻³ μM to BPP-II, 7 × 10⁻³ μM to BPP-III, and 3.3 ×10⁻³ μM to BPP-V. The amino acid sequence of the BPP-III has been determined to be pGlu-Gly-Gly-Trp-Pro-Arg-Pro-Gly-Pro-Glu-Ile-Pro-Pro, and the amino acid compositions of the BPP-II and BPP-V by amino acid analysis were 2Glu-2Gly-1Arg-4Pro-lIle and 2Glu-2Gly-lSer-3Pro-2Val-Ille, with molecular weight of 1372, 1046, and 1078, respectively.