Fig. 5

The codon-pair context map of optimized sequences of MT1-MMP E2C6 and ADAM17 A9B8. In order to better demonstrate codon-pair context of optimized sequences of MT1-MMP E2C6 and ADAM17 A9B8 based on CUB and CPB, the codons of optimized sequences were arranged into the map with 16 × 16 cells from left to right in sequence. Each cell in the map corresponds to a codon encoding a specific amino acid. The start codon ATG is displayed in the upper left corner of map and the stop codon TAA in the bottom right corner of map and the number of codons on the right of maps. The codon in the cell with its 5′ neighbor codon was colored in red for rejected contexts, green for preferred ones and black for ones without statistical significance. The intensity of red and green indicates the extent of the preference or rejection. CUB codon usage bias, CPB codon pair bias