Enterobacter aerogenes strain C2657B class 1 integron dihydrofolate reductase (dfrA12) and hypothetical protein genes, complete cds, disrupted streptomycin/spectinomycin 3' adenyltransferase (aadA2) gene, partial sequence, and insertion sequence IS26 TnpA transposase (tnpA) gene, partial cds