Figure 2
From: Transcriptional abundance is not the single force driving the evolution of bacterial proteins
Plots of correspondence analysis of relative synonymous codon usage (RSCU-CA). PC1 is the first principal component and PC2 is the second one. Ribosomal and non-ribosomal genes are represented by red and blue dots, respectively. Significantly different codon usages were observed between ribosomal proteins and other proteins in the genome of (A) E. coli, but were not observed in the genome of (B) H. pylori.