Catalyzes the exchange of L-arginine for agmatine. The arginine uptake by the bacterium in the macrophage may be a virulence factor against the host innate immune response (By similarity). Belongs to the amino acid-polyamine-organocation (APC) superfamily. Basic amino acid/polyamine antiporter (APA) (TC 2.A.3.2) family. CTA_0406, CTA_0407 and CTA_0408 have been merged into one gene. CTA_0406, CTA_0407 and CTA_0408 have been merged into one gene. CTA_0406, CTA_0407 and CTA_0408 have been merged into one gene.