E. coli genes with GFP scores higher than 4.2 have higher translation efficiency and protein abundance than other genes. (A) Density histogram of GFP scores for genes identified in E. coli for nucleotide composition at codon positions 3–5. As a control, we used a scrambled genome. Based on the GFP score, the E. coli genes were divided into two groups: genes with a score higher than 4.2 and scores lower than 4.2. Translation efficiency was measured in three independent studies, Morgan et al., 2018 [17](B), Li et al., 2014 [18](C) and Burkahardt et al., 2017 [19](D). (E) Protein abundance of genes with a score higher than 4.2 and score lower than 4.2. Kolmogorov-Smirnov nonparametric t-test, ****<0.0001, ***0.0004, *0.028. (F) Web Logo of nucleotide composition at codon positions 3–5 of E. coli genes or GFP library with a score higher than 4.2.