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Bacterial resistance occurs by spontaneous mutations or horizontal gene transfer mediated by mobile genetic elements, which represents a great concern. Resistance to β-lactam antibiotics is mainly due to the production of β-lactamases, and an important mechanism of fluoroquinolone resistance is the acquisition plasmid determinants. The aim of this study was to verify the presence of β-lactamase-encoding genes and plasmid-mediated quinolone resistance genes in different water samples obtained from São Paulo state, Brazil. A high level of these resistance genes was detected, being the bla, bla, and qnr the most prevalent. Besides that, the bla gene, which codify an important and hazardous metallo-β-lactamase, was detected.

The DNA puff BhC4-1 gene of Bradysia hygida (Diptera, Sciaridae) is amplified and expressed in the salivary glands at the end of the last larval instar. Even though there are no BhC4-1 orthologs in Drosophila melanogaster, the mechanisms that regulate BhC4-1 gene expression in B. hygida are for the most part conserved in D. melanogaster. The BhC4-1 promoter contains a 129bp (-186/-58) cis-regulatory module (CRM) that drives developmentally regulated expression in transgenic salivary glands at the onset of metamorphosis. Both in the sciarid and in transgenic D. melanogaster, BhC4-1 gene expression is induced by the increase in ecdysone titers that triggers metamorphosis. Genetic interaction experiments revealed that in the absence of the Eip74EF-PA early gene isoform BhC4-1-lacZ levels of expression in the salivary gland are severely reduced. Here we show that the overexpression of the Eip74EF-PA transcription factor is sufficient to anticipate BhC4-1-lacZ expression in transgenic D. melanogaster. Through yeast one-hybrid assays we confirm that the Eip74EF-PA transcription factor directly binds to the 129 bp sciarid CRM. Together, these results contribute to the characterization of an insect CRM and indicate that the ecdysone gene regulatory network that promotes metamorphosis is conserved between D. melanogaster and the sciarid B. hygida.