Figure 7

Bias of codon-triplets that vanished from ORFeomes. The number of possible codon-triplet combinations that were not present in fungal ORFeomes was surprisingly high. In order to elucidate why these triplets disappeared from ORFeomes, the respective codons were further studied, namely by counting the number of times each codon appeared in the first, second or third position of the triplets. No significant differences were found between species and between codon-triplet positions. Also, the first base of all codons originated redundant results. Therefore, values for all ORFeomes, triplet positions, and also for all codons starting with A, C, G or T were averaged. NCC, NCG and NGN codons were the most frequent codons in codon-triplets that were absent in fungal ORFeomes (red bars in panel B). Conversely, NAA codons were underrepresented in this group (yellow bar).