Part of the AaxABC system, catalyzes the decarboxylation of L-arginine. The arginine uptake by the bacterium in the macrophage may be a virulence factor against the host innate immune response (By similarity). H(+) + L-arginine = agmatine + CO2 Binds 1 pyruvoyl group covalently per subunit. Trimer of an alpha-beta dimer. Belongs to the pyruvoyl-dependent arginine decarboxylase family. Truncated C-terminus.