Putrescine importer. Required for induction of type 1 pili-driven surface motility. H(+)(in) + putrescine(in) = H(+)(out) + putrescine(out) Putrescine uptake is inhibited by carbonyl cyanide m-chlorophenylhydrazone (CCCP), which dissipates the proton motive force. Belongs to the amino acid-polyamine-organocation (APC) superfamily. Extended N-terminus.