FIGURE 4.

Distribution and abundance of MDRPs obtained from conjugation experiments in the absence (C) and presence of ZnSO₄ and CuSO₄ at 0.5 and 1 mM. Urban and agricultural areas in the La Paz River basin were used as the source of bacterial donor communities. A total of 28 MDRPs (P1–P28) were identified in 150 randomly selected transconjugants analyzed by the Kirby-Bauer Disk Diffusion Susceptibility Test to 13 antibiotics. Each identified profile was labeled with a distinctive color followed by the antibiotic resistance profile. Antibiotics whose transconjugants exhibited intermediate resistance are written in italics. Unique MDRPs per site are marked with a star (*), and they were only found with the addition of metals in conjugation experiments.