Identification of a glycine-like fragment on the strychnine molecule.

Strychnine, a complex molecule, antagonizes in some unknown manner the action of glycine, an important inhibitory neurotransmitter in the spinal cord and brainstem of many vertebrates. To help understand the mechanism of this antagonism, we have employed modern computational methods to assess the similarities between these seemingly different molecules. An exhaustive comparison of topological and electronic features of both molecules was made. We have successfully located a glycine-like fragment in the strychnine molecule that, when compared to glycine, exhibits both topological and electronic charge congruence. The successful location of this glycine-like fragment allows us to speculate how the large strychnine molecule assumes its role as an antagonist against the inhibitory action of glycine, the simplest amino acid.