Correlation between genomic GC content and amino acid frequency across the 461 species. The Pearson correlation coefficient (r) was calculated between amino acid frequencies and genomic GC content. The p values distribution was p = 0.0265 (Gln) and p < 0.0001 (others).
Chen et al. BMC Evolutionary Biology 2013 13:219 doi:10.1186/1471-2148-13-219