Figure 4.

Single linkage (Euclidean distances) clustering based on standardized amino acid usages (with respect to E. coli) of 12 Prochlorococcus strains and 4 other microbes, accompanied by a heatmap representation of the standardized amino acid usage values. The overrepresentation or underrepresentation of amino acid residues in the organisms are shown in green and red colored blocks of varying colour intensities, respectively. [Abbreviations, EC → E. coli; CJ → C. jejuni; GF → G. foresetii and CTH → Cyanothece sp.]