List of Abbreviations

Abbrev Organism Abbreviation
BP Base Pair
CA Correspondence Analysis
CAI Codon Adaptation Index
ID Gene Identification
HEG Highly Expressed Genes
Name Organism Name
NGenes Number of genes
RPG Ribosomal Protein Genes
RSCU Relative Synonymous Codon Usage
tRNA tRNA Gene Copy Number (or tGCN)

Translational selection and highly expressed genes

The methods for determining whether a genome is under translational selection and predicting highly expressed genes are described in the following article: Puigbo P, Guzman E, Romeu A and Garcia-Vallve S. OPTIMIZER: A web server for optimizing the codon usage of DNA sequences. Nucleic Acids Research. 2007. Vol. 35, No. suppl_2 W126-W131.

Correspondence Analysis of RSCU

To make the prediction of translational selection, we checked whether the mean position of the ribosomal protein genes along any of the four principal axes (Axis1, Axis2, Axis3 and Axis4) was significantly different (evaluated with a t-test - ns/*:<0.90/0.90 - **:0.95, ***:0.99, ****:0.9995) from the mean position of the other genes of their genome.