Genetic Determinants for Metal Tolerance and Antimicrobial Resistance Detected in Bacteria Isolated from Soils of Olive Tree Farms. - Related Documents




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370101.0000Genetic Determinants for Metal Tolerance and Antimicrobial Resistance Detected in Bacteria Isolated from Soils of Olive Tree Farms. Copper-derived compounds are often used in olive tree farms. In a previous study, a collection of bacterial strains isolated from olive tree farms were identified and tested for phenotypic antimicrobial resistance and heavy metal tolerance. The aim of this work was to study the genetic determinants of resistance and to evaluate the co-occurrence of metal tolerance and antibiotic resistance genes. Both metal tolerance and antibiotic resistance genes (including beta-lactamase genes) were detected in the bacterial strains from Cu-treated soils. A high percentage of the strains positive for metal tolerance genes also carried antibiotic resistance genes, especially for genes involved in resistances to beta-lactams and tetracycline. Significant associations were detected between genes involved in copper tolerance and genes coding for beta-lactamases or tetracycline resistance mechanisms. A significant association was also detected between zntA (coding for a Zn(II)-translocating P-type ATPase) and tetC genes. In conclusion, bacteria from soils of Cu-treated olive farms may carry both metal tolerance and antibiotic resistance genes. The positive associations detected between metal tolerance genes and antibiotic resistance genes suggests co-selection of such genetic traits by exposure to metals.202032756388
340110.9999Heavy metal resistance and virulence profile in Pseudomonas aeruginosa isolated from Brazilian soils. Pseudomonas aeruginosa is an opportunistic pathogen, which can have several virulence factors that confer on it the ability to cause severe, acute and chronic infections. Thus, the simultaneous occurrence of resistance to antibiotics and heavy metals associated with the presence of virulence genes is a potential threat to human health and environmental balance. This study aimed to investigate the resistance profile to heavy metals and the correlation of this phenotype of resistance to antimicrobials and to investigate the pathogenic potential of 46 P. aeruginosa isolates obtained from the soil of five Brazilian regions. The bacteria were evaluating for antimicrobial and heavy metal resistance, as well as the presence of plasmids and virulence genes. The isolates showed resistance to four different antibiotics and the majority (n = 44) had resistance to aztreonam or ticarcillin, furthermore, 32 isolates showed concomitant resistance to both of these antibiotics. A high prevalence of virulence genes was found, which highlights the pathogenic potential of the studied environmental isolates. Moreover, a high frequency of heavy metal resistance genes was also detected, however, the phenotypic results indicated that other genes and/or mechanisms should be related to heavy metal resistance.201627197940
340720.9999The culturable soil antibiotic resistome: a community of multi-drug resistant bacteria. Understanding the soil bacterial resistome is essential to understanding the evolution and development of antibiotic resistance, and its spread between species and biomes. We have identified and characterized multi-drug resistance (MDR) mechanisms in the culturable soil antibiotic resistome and linked the resistance profiles to bacterial species. We isolated 412 antibiotic resistant bacteria from agricultural, urban and pristine soils. All isolates were multi-drug resistant, of which greater than 80% were resistant to 16-23 antibiotics, comprising almost all classes of antibiotic. The mobile resistance genes investigated, (ESBL, bla NDM-1, and plasmid mediated quinolone resistance (PMQR) resistance genes) were not responsible for the respective resistance phenotypes nor were they present in the extracted soil DNA. Efflux was demonstrated to play an important role in MDR and many resistance phenotypes. Clinically relevant Burkholderia species are intrinsically resistant to ciprofloxacin but the soil Burkholderia species were not intrinsically resistant to ciprofloxacin. Using a phenotypic enzyme assay we identified the antibiotic specific inactivation of trimethoprim in 21 bacteria from different soils. The results of this study identified the importance of the efflux mechanism in the soil resistome and variations between the intrinsic resistance profiles of clinical and soil bacteria of the same family.201323776501
370330.9999Antibiotic resistance patterns of metal-tolerant bacteria isolated from an estuary. Estuarine bacteria isolated on metal-containing media were also found to be antibiotic resistant; ampicillin and chloramphenicol were the antibiotics to which resistance was most common. Patterns of antibiotic resistance were found associated with a variety of taxa.1977921251
340840.9999The role of aquatic ecosystems as reservoirs of antibiotic resistant bacteria and antibiotic resistance genes. The widespread and indiscriminate use of antibiotics has led to the development of antibiotic resistance in pathogenic, as well as commensal, microorganisms. Resistance genes may be horizontally or vertically transferred between bacterial communities in the environment. The recipient bacterial communities may then act as a reservoir of these resistance genes. In this study, we report the incidence of antibiotic resistance in enteric bacteria isolated from the Mhlathuze River and the distribution of genetic elements that may be responsible for the observed antibiotic resistance. The resistance of the enteric bacteria isolated over a period of one year showed that resistance to the older classes of antibiotics was high (94.7% resistance to one antibiotic and 80.8% resistance to two antibiotics). Furthermore, antibiotic resistance data of the environmental isolates showed a strong correlation (r = 0.97) with data obtained from diarrhoea patients. PCR based methods demonstrated that class 1 integrons were present in >50% of the environmental bacterial isolates that were resistant to multiple antibiotics. This class of integrons is capable of transferring genes responsible for resistance to beta-lactam, aminoglycoside, sulfonamide and quaternary ammonium antimicrobial agents. Conjugate plasmids were also isolated, but from a small percentage of isolates. This study showed that the Mhlathuze River (a) is a medium for the spread of bacterial antibiotic resistance genes, (b) acts as a reservoir for these genes and (c) due to socio-economic pressures, may play a role in the development and evolution of these genes along this river system.200415318485
457150.9998Growth of soil bacteria, on penicillin and neomycin, not previously exposed to these antibiotics. There is growing evidence that bacteria, in the natural environment (e.g. the soil), can exhibit naturally occurring resistance/degradation against synthetic antibiotics. Our aim was to assess whether soils, not previously exposed to synthetic antibiotics, contained bacterial strains that were not only antibiotic resistant, but could actually utilize the antibiotics for energy and nutrients. We isolated 19 bacteria from four diverse soils that had the capability of growing on penicillin and neomycin as sole carbon sources up to concentrations of 1000 mg L(-1). The 19 bacterial isolates represent a diverse set of species in the phyla Proteobacteria (84%) and Bacteroidetes (16%). Nine antibiotic resistant genes were detected in the four soils but some of these genes (i.e. tetM, ermB, and sulI) were not detected in the soil isolates indicating the presence of unculturable antibiotic resistant bacteria. Most isolates that could subsist on penicillin or neomycin as sole carbon sources were also resistant to the presence of these two antibiotics and six other antibiotics at concentrations of either 20 or 1000 mg L(-1). The potentially large and diverse pool of antibiotic resistant and degradation genes implies ecological and health impacts yet to be explored and fully understood.201424956077
360160.9998R factors mediate resistance to mercury, nickel, and cobalt. Fifty-five clinical isolates and laboratory stocks of Escherichia coli and Salmonella were studied for resistance to each of ten metals. Eleven clinical isolates carrying R factors were resistant to mercury, and, in each case, the resistance was mediated by a previously undefined R-factor gene. The gene was phenotypically expressed within 2 to 4 minutes after entry into sensitive bacteria, but the basis for the resistance remains undefined. Fourteen strains, 12 infected with R factors, were resistant to cobalt and nickel, but these resistances were mediated by R-factor genes in only two strains; separate R-factor genes mediated the resistances to nickel and cobalt. These and other results indicate that the genetic composition of R factors is greater than that originally defined.19675337360
457270.9998Effect of high pressure processing on changes in antibiotic resistance genes expression among strains from commercial starter cultures. This study analyzed the effect of high-pressure processing on the changes in resistance phenotype and expression of antibiotic resistance genes among strains from commercial starter cultures. After exposure to high pressure the expression of genes encoding resistance to aminoglycosides (aac(6')Ie-aph(2″)Ia and aph(3')-IIIa) decreased and the expression of genes encoding resistance to tetracyclines (tetM and tetW), ampicillin (blaZ) and chloramphenicol (cat) increased. Expression changes differed depending on the pressure variant chosen. The results obtained in the gene expression analysis correlated with the results of the phenotype patterns. To the best of the authors' knowledge, this is one of the first studies focused on changes in antibiotic resistance associated with a stress response among strains from commercial starter cultures. The results suggest that the food preservation techniques might affect the phenotype of antibiotic resistance among microorganisms that ultimately survive the process. This points to the need to verify strains used in the food industry for their antibiotic resistance as well as preservation parameters to prevent the further increase in antibiotic resistance in food borne strains.202336462825
370280.9998Antibiotic and metal resistance of Stenotrophomonas maltophilia isolates from Eboling permafrost of the Tibetan Plateau. Whole-genome sequencing of pathogenic bacteria Stenotrophomonas maltophilia from a less polluted environment of permafrost can help understand the intrinsic resistome of both antibiotics and metals. This study aimed to examine the maximum minimum inhibitory concentration (MIC) of both antibiotics and metals, as well as antibiotic resistance genes and metal resistance genes annotated from whole-genome sequences. The permafrost S. maltophilia was sensitive to ciprofloxacin, tetracycline, streptomycin, and bacitracin, and resistant to chloramphenicol, trimethoprim-sulfamethoxazole, erythromycin, Zn(2+), Ni(2+), Cu(2+), and Cr(6+), with a lower maximum MIC, compared with clinical S. maltophilia. The former strain belonged to the lower antibiotic resistance gene (ARG) and metal resistance gene (MRG) clusters compared with the latter ones. The permafrost strain contained no or only one kind of ARG or MRG on a single genomic island, which explained the aforementioned lower maximum MIC and less diversity of ARGs or MRGs. The result indicated that the co-occurrence of antibiotic and metal resistance was due to a certain innate ability of S. maltophilia. The continuous human use of antibiotics or metals induced selective pressure, resulting in higher MIC and more diverse ARGs and MRGs in human-impacted environments.202336097311
339190.9998Phenotypic and genotypic analysis of bacteria isolated from three municipal wastewater treatment plants on tetracycline-amended and ciprofloxacin-amended growth media. AIMS: The goal of this study was to determine the antimicrobial susceptibility of bacteria isolated from three municipal wastewater treatment plants. METHODS AND RESULTS: Numerous bacterial strains were isolated from three municipal wastewater treatment facilities on tetracycline- (n=164) and ciprofloxacin-amended (n=65) growth media. These bacteria were then characterized with respect to their resistance to as many as 10 different antimicrobials, the presence of 14 common genes that encode resistance to tetracycline, the presence of integrons and/or the ability to transfer resistance via conjugation. All of the characterized strains exhibited some degree of multiple antimicrobial resistance, with nearly 50% demonstrating resistance to every antimicrobial that was tested. Genes encoding resistance to tetracycline were commonly detected among these strains, although intriguingly the frequency of detection was slightly higher for the bacteria isolated on ciprofloxacin-amended growth media (62%) compared to the bacteria isolated on tetracycline-amended growth media (53%). Class 1 integrons were also detected in 100% of the queried tetracycline-resistant bacteria and almost half of the ciprofloxacin-resistant strains. Conjugation experiments demonstrated that at least one of the tetracycline-resistant bacteria was capable of lateral gene transfer. CONCLUSIONS: Our results demonstrate that multiple antimicrobial resistance is a common trait among tetracycline-resistant and ciprofloxacin-resistant bacteria in municipal wastewater. SIGNIFICANCE AND IMPACT OF THE STUDY: These organisms are potentially important in the proliferation of antimicrobial resistance because they appear to have acquired multiple genetic determinants that confer resistance and because they have the potential to laterally transfer these genetic determinants to strains of clinical importance.201020629799
3704100.9998Antibiotic resistance in bacteria isolated from the deep terrestrial subsurface. Various natural environments have been examined for the presence of antibiotic-resistant bacteria and/or novel resistance mechanisms, but little is known about resistance in the terrestrial deep subsurface. This study examined two deep environments that differ in their known period of isolation from surface environments and the bacteria therein. One hundred fifty-four strains of bacteria were isolated from sediments located 170-259 m below land surface at the US Department of Energy Savannah River Site (SRS) in South Carolina and Hanford Site (HS) in Washington. Analyses of 16S rRNA gene sequences showed that both sets of strains were phylogenetically diverse and could be assigned to several genera in three to four phyla. All of the strains were screened for resistance to 13 antibiotics by plating on selective media and 90% were resistant to at least one antibiotic. Eighty-six percent of the SRS and 62% of the HS strains were resistant to more than one antibiotic. Resistance to nalidixic acid, mupirocin, or ampicillin was noted most frequently. The results indicate that antibiotic resistance is common among subsurface bacteria. The somewhat higher frequencies of resistance and multiple resistance at the SRS may, in part, be due to recent surface influence, such as exposure to antibiotics used in agriculture. However, the HS strains have never been exposed to anthropogenic antibiotics but still had a reasonably high frequency of resistance. Given their long period of isolation from surface influences, it is possible that they possess some novel antibiotic resistance genes and/or resistance mechanisms.200918677528
3394110.9998Antibiotic resistance patterns of Pseudomonas spp. isolated from faecal wastes in the environment and contaminated surface water. The Pseudomonas genus, which includes environmental and pathogenic species, is known to present antibiotic resistances, and can receive resistance genes from multi-resistant enteric bacteria released into the environment via faecal rejects. This study was aimed to investigate the resistome of Pseudomonas populations that have been in contact with these faecal bacteria. Thus, faecal discharges originating from human or cattle were sampled (from 12 points and two sampling campaigns) and 41 Pseudomonas species identified (316 isolates studied). The resistance phenotype to 25 antibiotics was determined in all isolates, and we propose a specific antibiotic resistance pattern for 14 species (from 2 to 9 resistances). None showed resistance to aminoglycosides, tetracycline, or polymyxins. Four species carried a very low number of resistances, with none to β-lactams. Interestingly, we observed the absence of the transcriptional activator soxR gene in these four species. No plasmid transfer was highlighted by conjugation assays, and a few class 1 but no class 2 integrons were detected in strains that may have received resistance genes from Enterobacteria. These results imply that the contribution of the Pseudomonas genus to the resistome of an ecosystem first depends on the structure of the Pseudomonas populations, as they may have very different resistance profiles.202031930390
3705120.9998Widespread occurrence of bacterial human virulence determinants in soil and freshwater environments. The occurrence of 22 bacterial human virulence genes (encoding toxins, adhesins, secretion systems, regulators of virulence, inflammatory mediators, and bacterial resistance) in beech wood soil, roadside soil, organic agricultural soil, and freshwater biofilm was investigated by nested PCR. The presence of clinically relevant bacterial groups known to possess virulence genes was tested by PCR of 16S and 23S rRNA genes. For each of the virulence genes detected in the environments, sequencing and NCBI BLAST analysis confirmed the identity of the PCR products. The virulence genes showed widespread environmental occurrence, as 17 different genes were observed. Sixteen genes were detected in beech wood soil, and 14 were detected in roadside and organic agricultural soils, while 11 were detected in the freshwater biofilm. All types of virulence traits were represented in all environments; however, the frequency at which they were detected was variable. A principal-component analysis suggested that several factors influenced the presence of the virulence genes; however, their distribution was most likely related to the level of contamination by polycyclic aromatic hydrocarbons and pH. The occurrence of the virulence genes in the environments generally did not appear to be the result of the presence of clinically relevant bacteria, indicating an environmental origin of the virulence genes. The widespread occurrence of the virulence traits and the high degree of sequence conservation between the environmental and clinical sequences suggest that soil and freshwater environments may constitute reservoirs of virulence determinants normally associated with human disease.201323835169
3871130.9998Functional characterization of bacteria isolated from ancient arctic soil exposes diverse resistance mechanisms to modern antibiotics. Using functional metagenomics to study the resistomes of bacterial communities isolated from different layers of the Canadian high Arctic permafrost, we show that microbial communities harbored diverse resistance mechanisms at least 5,000 years ago. Among bacteria sampled from the ancient layers of a permafrost core, we isolated eight genes conferring clinical levels of resistance against aminoglycoside, β-lactam and tetracycline antibiotics that are naturally produced by microorganisms. Among these resistance genes, four also conferred resistance against amikacin, a modern semi-synthetic antibiotic that does not naturally occur in microorganisms. In bacteria sampled from the overlaying active layer, we isolated ten different genes conferring resistance to all six antibiotics tested in this study, including aminoglycoside, β-lactam and tetracycline variants that are naturally produced by microorganisms as well as semi-synthetic variants produced in the laboratory. On average, we found that resistance genes found in permafrost bacteria conferred lower levels of resistance against clinically relevant antibiotics than resistance genes sampled from the active layer. Our results demonstrate that antibiotic resistance genes were functionally diverse prior to the anthropogenic use of antibiotics, contributing to the evolution of natural reservoirs of resistance genes.201525807523
3409140.9998Antibiotic resistance genes in the bacteriophage DNA fraction of environmental samples. Antibiotic resistance is an increasing global problem resulting from the pressure of antibiotic usage, greater mobility of the population, and industrialization. Many antibiotic resistance genes are believed to have originated in microorganisms in the environment, and to have been transferred to other bacteria through mobile genetic elements. Among others, β-lactam antibiotics show clinical efficacy and low toxicity, and they are thus widely used as antimicrobials. Resistance to β-lactam antibiotics is conferred by β-lactamase genes and penicillin-binding proteins, which are chromosomal- or plasmid-encoded, although there is little information available on the contribution of other mobile genetic elements, such as phages. This study is focused on three genes that confer resistance to β-lactam antibiotics, namely two β-lactamase genes (blaTEM and blaCTX-M9) and one encoding a penicillin-binding protein (mecA) in bacteriophage DNA isolated from environmental water samples. The three genes were quantified in the DNA isolated from bacteriophages collected from 30 urban sewage and river water samples, using quantitative PCR amplification. All three genes were detected in the DNA of phages from all the samples tested, in some cases reaching 104 gene copies (GC) of blaTEM or 102 GC of blaCTX-M and mecA. These values are consistent with the amount of fecal pollution in the sample, except for mecA, which showed a higher number of copies in river water samples than in urban sewage. The bla genes from phage DNA were transferred by electroporation to sensitive host bacteria, which became resistant to ampicillin. blaTEM and blaCTX were detected in the DNA of the resistant clones after transfection. This study indicates that phages are reservoirs of resistance genes in the environment.201121390233
3600150.9998Uncultured soil bacteria are a reservoir of new antibiotic resistance genes. Antibiotic resistance genes are typically isolated by cloning from cultured bacteria or by polymerase chain reaction (PCR) amplification from environmental samples. These methods do not access the potential reservoir of undiscovered antibiotic resistance genes harboured by soil bacteria because most soil bacteria are not cultured readily, and PCR detection of antibiotic resistance genes depends on primers that are based on known genes. To explore this reservoir, we isolated DNA directly from soil samples, cloned the DNA and selected for clones that expressed antibiotic resistance in Escherichia coli. We constructed four libraries that collectively contain 4.1 gigabases of cloned soil DNA. From these and two previously reported libraries, we identified nine clones expressing resistance to aminoglycoside antibiotics and one expressing tetracycline resistance. Based on the predicted amino acid sequences of the resistance genes, the resistance mechanisms include efflux of tetracycline and inactivation of aminoglycoside antibiotics by phosphorylation and acetylation. With one exception, all the sequences are considerably different from previously reported sequences. The results indicate that soil bacteria are a reservoir of antibiotic resistance genes with greater genetic diversity than previously accounted for, and that the diversity can be surveyed by a culture-independent method.200415305923
3872160.9998Functional metagenomic analysis reveals rivers are a reservoir for diverse antibiotic resistance genes. The environment harbours a significant diversity of uncultured bacteria and a potential source of novel and extant resistance genes which may recombine with clinically important bacteria disseminated into environmental reservoirs. There is evidence that pollution can select for resistance due to the aggregation of adaptive genes on mobile elements. The aim of this study was to establish the impact of waste water treatment plant (WWTP) effluent disposal to a river by using culture independent methods to study diversity of resistance genes downstream of the WWTP in comparison to upstream. Metagenomic libraries were constructed in Escherichia coli and screened for phenotypic resistance to amikacin, gentamicin, neomycin, ampicillin and ciprofloxacin. Resistance genes were identified by using transposon mutagenesis. A significant increase downstream of the WWTP was observed in the number of phenotypic resistant clones recovered in metagenomic libraries. Common β-lactamases such as blaTEM were recovered as well as a diverse range of acetyltransferases and unusual transporter genes, with evidence for newly emerging resistance mechanisms. The similarities of the predicted proteins to known sequences suggested origins of genes from a very diverse range of bacteria. The study suggests that waste water disposal increases the reservoir of resistance mechanisms in the environment either by addition of resistance genes or by input of agents selective for resistant phenotypes.201424636906
3597170.9998Evidence for extensive resistance gene transfer among Bacteroides spp. and among Bacteroides and other genera in the human colon. Transfer of antibiotic resistance genes by conjugation is thought to play an important role in the spread of resistance. Yet virtually no information is available about the extent to which such horizontal transfers occur in natural settings. In this paper, we show that conjugal gene transfer has made a major contribution to increased antibiotic resistance in Bacteroides species, a numerically predominant group of human colonic bacteria. Over the past 3 decades, carriage of the tetracycline resistance gene, tetQ, has increased from about 30% to more than 80% of strains. Alleles of tetQ in different Bacteroides species, with one exception, were 96 to 100% identical at the DNA sequence level, as expected if horizontal gene transfer was responsible for their spread. Southern blot analyses showed further that transfer of tetQ was mediated by a conjugative transposon (CTn) of the CTnDOT type. Carriage of two erythromycin resistance genes, ermF and ermG, rose from <2 to 23% and accounted for about 70% of the total erythromycin resistances observed. Carriage of tetQ and the erm genes was the same in isolates taken from healthy people with no recent history of antibiotic use as in isolates obtained from patients with Bacteroides infections. This finding indicates that resistance transfer is occurring in the community and not just in clinical environments. The high percentage of strains that are carrying these resistance genes in people who are not taking antibiotics is consistent with the hypothesis that once acquired, these resistance genes are stably maintained in the absence of antibiotic selection. Six recently isolated strains carried ermB genes. Two were identical to erm(B)-P from Clostridium perfringens, and the other four had only one to three mismatches. The nine strains with ermG genes had DNA sequences that were more than 99% identical to the ermG of Bacillus sphaericus. Evidently, there is a genetic conduit open between gram-positive bacteria, including bacteria that only pass through the human colon, and the gram-negative Bacteroides species. Our results support the hypothesis that extensive gene transfer occurs among bacteria in the human colon, both within the genus Bacteroides and among Bacteroides species and gram-positive bacteria.200111157217
4573180.9998High pressure processing, acidic and osmotic stress increased resistance to aminoglycosides and tetracyclines and the frequency of gene transfer among strains from commercial starter and protective cultures. This study analyzed the effect of food-related stresses on the expression of antibiotic resistance of starter and protective strains and resistance gene transfer frequency. After exposure to high-pressure processing, acidic and osmotic stress, the expression of genes encoding resistance to aminoglycosides (aac(6')Ie-aph(2″)Ia and aph(3')-IIIa) and/or tetracyclines (tetM) increased. After cold stress, a decrease in the expression level of all tested genes was observed. The results obtained in the gene expression analysis correlated with the results of the phenotype patterns. After acidic and osmotic stresses, a significant increase in the frequency of each gene transfer was observed. To the best of the authors' knowledge, this is the first study focused on changes in antibiotic resistance associated with a stress response among starter and protective strains. The results suggest that the physicochemical factors prevailing during food production and storage may affect the phenotype of antibiotic resistance and the level of expression of antibiotic resistance genes among microorganisms. As a result, they can contribute to the spread of antibiotic resistance. This points to the need to verify strains used in the food industry for their antibiotic resistance to prevent them from becoming a reservoir for antibiotic resistance genes.202235953184
3358190.9998Novel class 1 integron harboring antibiotic resistance genes in wastewater-derived bacteria as revealed by functional metagenomics. Combatting antibiotic resistance is critical to our ability to treat infectious diseases. Here, we identified and characterized diverse antimicrobial resistance genes, including potentially mobile elements, from synthetic wastewater treatment microcosms exposed to the antibacterial agent triclosan. After seven weeks of exposure, the microcosms were subjected to functional metagenomic selection across 13 antimicrobials. This was achieved by cloning the combined genetic material from the microcosms, introducing this genetic library into E. coli, and selecting for clones that grew on media supplemented with one of the 13 antimicrobials. We recovered resistant clones capable of growth on media supplemented with a single antimicrobial, yielding 13 clones conferring resistance to at least one antimicrobial agent. Antibiotic susceptibility analysis revealed resistance ranging from 4 to >50 fold more resistant, while one clone showed resistance to multiple antibiotics. Using both Sanger and SMRT sequencing, we identified the predicted active gene(s) on each clone. One clone that conferred resistance to tetracycline contained a gene encoding a novel tetA-type efflux pump that was named TetA(62). Three clones contained predicted active genes on class 1 integrons. One integron had a previously unreported genetic arrangement and was named In1875. This study demonstrated the diversity and potential for spread of resistance genes present in human-impacted environments.202133515651