Structure determination of a tetradecapeptide mimicking the RXVRG consensus sequence recognized by a Xenopus laevis skin endoprotease: an approach based on simulated annealing and 1H NMR.

The tetradecapeptide of sequence H-Asp-Val-Asp-Glu-Arg5-Asp-Val-Arg-Gly9-Phe-Ala-Ser-Phe-Leu- NH2 is recognized by a putative maturation endoprotease of the Xenopus laevis skin, which cleaves between Arg8 and Gly9. A conformational search has been performed on this peptide by simulated annealing calculations. Two different models in agreement with the NMR data were found. The conformational difference between the two types of model is located in the consensus sequence, i.e., from Arg5 to Gly9.