Catalyzes the sodium-dependent uptake of extracellular L-proline (By similarity). Since most S.aureus strains are L-proline auxotrophs, this transporter may aid the bacterial persistence during an infection of tissues with low proline concentrations (By similarity). L-proline(in) + Na(+)(in) = L-proline(out) + Na(+)(out) Belongs to the sodium:solute symporter (SSF) (TC 2.A.21) family.