[i] ^aThe amino acid and the average GC content of all synonymous codons.

[ii] ^bNumber of GC pairs (in the codon–anticodon pairing).

[iii] ^cCodon sequences. Codons for each amino acid are sorted by increasing GC content of the codon–anticodon pairing.

[iv] ^dRSCU (Relative Synonymous Codon Usage) (Sharp and Li 1987) value computed over the CDS of the whole genome and the value over CDS of C-left only. As a general rule (except Arg AGA, Arg CGC, and Ser AGC), RSCU values of the synonymous codon harboring the largest number of GC pairs in the codon–anticodon pairing are higher in C-left compared with the whole genome (shown as “<”), while for the others, RSCU values are lower (“>”). The highest RSCU values in the whole genome and C-left for a given amino acid are shown in bold.

[v] ^eNumber of tRNA genes bearing the cognate anticodon.