Fig. 1

The β-lactamases genes carried by K.pneumoniae and E.coli strains. Based on the neighbor-joining method, the phylogenetic tree was constructed by comparing the 16SrDNA sequences of K.pneumoniae (A) and E.coli strains (B). The β-Lactamases genes of bla_SHV (red), bla_TEM−1 (yellow), bla_CTX−M−9 (green), bla_IMP (blue), and bla_NDM−1 (purple) amplified by PCR were placed on the right side of the strain, but this did not indicate the location of these genes in the genome of the strain