The activity of AaaA enables <i>P. aeruginosa</i> to grow using the tripeptide arg-gly-asp as the sole source of carbon and nitrogen.

<p><i>P. aeruginosa</i> PAO1 (closed circles) and its derived <i>aaaA</i> deficient mutant (Δ<i>aaaA</i>, open circles) alone or bearing pME6032 (vector, open triangles) or pME6032::<i>aaaA</i> (complemented, closed triangles) were grown to mid-exponential phase before the induction of AaaA production by 1 mM IPTG. Cells were resuspended in MMP to OD₆₀₀ of 1, and subsequently 20 µl of this solution diluted into 200 µl of MMP containing arginine at 10 mM (<b>Panel A</b>), or 10 mM of the tripeptide arg-gly-asp (<b>Panel B</b>). The graph shows the subsequent growth in the Tecan monitored by observing the increase in OD₄₉₂ over time. The data is representative of 3 independent repetitions of this experiment.