Effect of the localization of an amino acid residue on utilization of a dipeptide.

<p>The middle square boxes represent the specific amino acid. The background color of the box gives information about the chemical nature of the specific side-chain group. The left and right arms of a box indicate the localization of the amino acid either at the N- or C-terminal end of the dipeptide. The numbers within the arms indicate how many dipeptides of this group were utilized by the different strains. The colors within the arms indicate the percentage of dipeptides used by a strain (see legend) related to the total amount of dipeptides used by the wild type.