Conservation profile of 16S rRNA three-dimensional structure; Screenshot showing the conservation profile or positional variability information superimposed onto the 3D structure of small subunit rRNA. Column statistics are performed on the multiple alignments using parsimony method and minimum number of mutations for each site is determined. The positional variability values are then overlaid onto the 3D structure of 16S rRNA of Escherichia coli residue-by-residue to generate 3D positional variability maps. Residues inclining towards yellow are highly variable where as the residues inclining towards red are highly conserved positions. It is apparent that the highly variable residues are located on the periphery of the 3D structure while the highly conserved residues are centralized at the core of the structure. Conservation profile was calculated with the data set containing around 40,000 complete 16S rRNA sequences.