Crystallization and preliminary x-ray diffraction study of neurotoxin-I from Naja naja oxiana VENOM

Abstract

Crystals of the neurotoxin-I (NTX-I) from the venom of the middle Asian cobra Naja naja oxiana have been grown by vapour diffusion and dialysis methods. The crystals belong to space group P2 12 12 with dimension of a = 25.19 Å, b = 75.59 Å, c = 36.09 Å and diffract to 1.9 Å resolution. The asymmetric unit contains one molecule ( V m = 2.2 Å/Da). Using the molecule of α-cobratoxin (CTX) as a starting model for NTX-I structure determination coordinates of Cα atoms of the NTX-I molecule were obtained and the position of NTX-I in the unit cell was derived.