Figure 1

Conjugation experiments of plasmids carrying β la _KPC -2 and -3 from parental non-serotype K2 K. pneumoniae to recipient serotype K2 K. pneumoniae . In this conjugation experiment, plasmids carrying blaKPC from KPC-positive K. pneumoniae (KPC-2 and -3) were successfully transferred into the invasive K2 K. pneumoniae recipient isolate (NJ-K2). Specifically, DNA extracted from the invasive K2 K. pneumoniae recipient isolate (NJ-K2) were positive for the blaKPC gene by PCR. Transconjugants, K2 K. pneumoniae::βla_KPC, were obtained by Klebsiella-selective medium BIND supplemented with 2 µg/ml of imipenem. Colonies were then randomly selected from the plate and subjected for serotype K2 PCR. Colonies with PCR positive results on serotype determination were sub-cultured onto the same selective agar plate. Sub-culture of K2 K. pneumoniae:: βla_KPC occurred by inoculating onto MacConkey agar plates for 14 consecutive days. Lane 1, PCR verification of recipient serotype K2 isolate from New Jersey; Lane 2, Control KPC-2 from Taiwan; Lane 3, donor K. pneumoniae with βla_KPC-2, Lane 4, transconjugants K. pneumoniae::βla_KPC-2.