Imipenem resistance in Klebsiella pneumoniae is associated with the combination of ACT-1, a plasmid-mediated AmpC beta-lactamase, and the loss of an outer membrane protein - Bradford,P.A.; Urban,C.; Mariano,N.; Projan,S.J.; Rahal,J.J.; Bush,K. (Antimicrob Agents Chemother, 1997)