The protein structure of crotamine could not be initially determined through protein crystallization nor X-ray diffraction. It was speculated that the difficulty was because crotamine has so many isoforms, leading to the formation of aggregates and different possible conformations of the protein. The structure and the shape of the protein was proposed through a 3D model generated by Siqueira et al. (2002) based on computational calculations that were supported with intensive molecular dynamics simulations and homology modeling procedures. Afterwards, Nicastro et al. (2003) discovered the structure of crotamine through nuclear magnetic resonance spectroscopy. Crotamine has a topology that was never before seen in active toxins that target ion channels; the protein is composed of a short N-terminal alpha helix, a type of protein formation, and a small antiparallel triple-stranded beta-sheet, another type of protein formation, arranged in an ab1b2b3 topology. Crotamine has similar structural fold conformations to the human b-defensin family as well as identical disulfide bridges arrangement.