Global utilization pattern of dipeptides by PA14, the dipeptide transporter DppBCDF and the SBPs DppA1–A5.

<p>The rings show the total number of dipeptides utilized by the wild-type strain PA14 (outer purple ring), transported by the dipeptide transporter system DppBCDF (middle blue ring), and recognized by the substrate-binding proteins (inner dark green ring). The oval rings (green) present different pools of dipeptides (nonpolar, acidic, uncharged) containing a specific amino acid side-chain either at the N- or C-terminal end of the dipeptide (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0111311#pone-0111311-t002" target="_blank">Table 2</a>). Dipeptides containing positively charged amino acid residues were excluded from the analysis (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0111311#s4" target="_blank">Materials and Methods</a>).