Table 3.
Summary of studies characterizing environmental resistomes through functional metagenomics.
| Environment | # of Clones (Bases) | # of Resistant Clones/ARs Sequenced | Resistance Gene | Reference |
|---|---|---|---|---|
| Soil (Alaskan) | 714,000 (12.4Gb) |
14 | β-Lactamase | [57] |
| Soil (Apple orchard) | 446,000 (13 Gb) |
13 | β-Lactamase, aminoglycoside acetyltransferases, efflux pump | [75] |
| Soil (Urban environment) | 1,400,000 (2.8 Gb) |
39 | Aminoglycoside acetyltransferases, rifampin ADP-ribosyltransferases, dihydrofolate reductases, transporters |
[58] |
| Soil (Agricultural and grassland) | (13.8 Gb) | 2895 | β-Lactamase, transporters, Aminoglycoside acetyltransferases | [59] |
| Soil (Agricultural) | 80,000 | 45 | aminoglycoside acetyltransferase, aminoglycoside 6-adenyltransferase, ADP-ribosyl transferase, ribosome protection protein, transporters | [76] |
| Water (Agro-industrial wastewater) | 200,000 | 1 | Multidrug resistance protein from Bcr/CflA subfamily | [77] |
| Water (WWTP) | 7,618 | 1 | β-Lactamase | [65] |
| Activated sludge | (1.85 Gb) | 9 | O-Methyltransferase, β-Lactamase, aminoglycoside phosphotransferase | [78] |
| Activated sludge | 400,000 (800 Mb) |
79 | β-Lactamase, Aminoglycoside phosphotransferase, dihydrofolate reductase, rifampin ADP-ribosyl transferase | [64] |