Abstract

Conformational Study on Pheromonotropin neuropeptide using NMR and Molecular Dynamics

Deep Bhattacharya, Nitin Mishra, Evans C Coutinho, Sudha Srivastava, Raghuvir RS Pissurlenkar and Mushtaque Shaikh

Pheromonotropic neuropeptide, Pseudaletia pheromonotropin, is an 18 amino acid peptide with the sequence Lys-Leu-Ser-Tyr-Asp-Asp-Lys-Val-Phe-Glu-Asn-Val-Glu-Phe-Thr-Pro-Arg-Leu which is widely distributed in female moths of Bombyx mori. This peptide is structurally related to leucopyrokinin, an insect myotropic neuropeptide, responsible for melanization and reddish coloration hormone (MRCH) activity. A combined NMR and Molecular Dynamics (MD) methods were used to fathom the conformational behaviour in water which was used as a solvent. The structure was investigated using 1D-NMR and 2D-NMR (COSY, TOCSY and ROESY) experiments. The conformation was built by constrained MD simulations using distance and dihedral restraints from NMR data in the GROMACS simulation package. The peptide predominately adopts a β-sheet structure in water.