Figure 3

Summary of correlation of expression results with physical features of the transmembrane proteins. For each category of each characteristic, the numbers of proteins expressed (grey bars) and not expressed (black bars) are indicated. A. Number of transmembrane helices. Transmembrane proteins with fewer TMH tended to be expressed more often than those with a greater number of TMH. Those proteins that were not expressed had on average more than 7 TMH, while those that were expressed had on average fewer than 6 TMH (Chi-square test p value = 0.005). B. Percentage of amino acids in transmembrane helices versus in periplasmic or cytoplasmic loops and domains. Proteins that were expressed tended to have fewer of their amino acids in the TMHs than those proteins that were not expressed (Chi-square test for trend p value = 0.005). C. Grand average of hydropathicity (GRAVY). Proteins that were not expressed had a higher average GRAVY score (Chi-square test for trend p value 0.008).