Figure 7. Leucine codon use plotted against the genomic GC content of the representative bacteria among the following groups.

A) Alphaproteobacteria; B) Betaproteobacteria; C) Gammaproteobacteria; D) Deltaproteobacteria; E) Actinobacteria; F) Bacteriodetes/Chlorobi; G) Cyanobacteria; H) Firmicutes. Leu-T and Leu-C refer to leucine codon families with either a T or a C in the first codon position, respectively.