Table 2.

Isoleucine and arginine codon usagea

GeneCodon usageb
Ile (AUU)Ile (AUC)Ile (AUA)Arg (CGC)Arg (CGU)Arg (CGG)Arg (CGA)Arg (AGA)Arg (AGG)
E. coli K-12 genome30.325.14.422.020.95.43.62.11.2
E. coli K-12 all ORFs30.824.55.221.420.35.74.02.71.7
933W genome22.919.310.115.219.28.96.59.96.0
933W all ORFs24.223.212.514.514.09.07.911.66.6
933WstxA 9.46.346.96.328.19.46.318.86.3
933WstxB 11.111.10.011.10.00.00.00.00.0
933Wstk 22.92.948.70.08.65.70.025.811.5
  • a For E. coli K-12 (4,290 ORFs, 1,363,501 codons) and bacteriophage 933W (78 ORFs, 18,246 codons), codon usage was calculated for each genome (i.e., all codons) and for each ORF individually.

  • b Values are expressed as codon frequency per 1,000 codons; for “all ORFs,” the mean of the individual ORF values is shown.