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1.
Int J Food Microbiol ; 351: 109263, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34116344

RESUMO

Campylobacter is the leading cause of foodborne human diarrhea worldwide. This microbe in the viable but non-culturable (VBNC) state can evade detection by routinely used culture-based methods and remain viable for extended periods of time. Bacteria in this dormancy state can resume their metabolic activity and virulence by resuscitation under favorable conditions, and subsequently cause infections. In this study, an assay combining loop-mediated isothermal amplification (LAMP) and propidium monoazide (PMA) treatment was developed for the detection and quantification of VBNC C. jejuni in agri-foods. PMA-qLAMP targeting the hipO gene demonstrated 100% high specificity to C. jejuni. A linear detection of C. jejuni was achieved between 8.77 × 102 and 8.77 × 07 CFU/mL with a coefficient of determination (R2) of 0.9956, indicating a good quantitative capacity. C. jejuni was effectively induced into the VBNC state by osmotic stress (i.e., 7% NaCl, w/v) over 48 h. VBNC C. jejuni cells were spiked into three representative food products and determined by PMA-qLAMP coupled with plating assay. The detection limits of PMA-qLAMP were 1.58 × 102 CFU/mL in milk, 3.78 × 102 CFU/g in chicken breast meat, and 4.33 × 102 CFU/g in romaine lettuce. PMA-qLAMP demonstrated rapid (25-40 min), specific (100% inclusivity and 100% exclusivity) and sensitive (~102 CFU/mL) determination of VBNC C. jejuni. This method can be applied in the agri-food industry to decrease the risks related to the consumption of contaminated agri-foods with pathogenic bacteria in the VBNC state and reduce the burden of C. jejuni infections to public health.


Assuntos
Campylobacter jejuni/isolamento & purificação , Microbiologia de Alimentos/métodos , Animais , Azidas , Campylobacter jejuni/genética , Galinhas , Genes Bacterianos/genética , Substâncias Intercalantes , Alface/microbiologia , Leite/microbiologia , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Aves Domésticas/microbiologia , Propídio/análogos & derivados , Sensibilidade e Especificidade
2.
Nat Commun ; 12(1): 3801, 2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34155204

RESUMO

The recent emergence of strains of Neisseria gonorrhoeae associated with treatment failures to ceftriaxone, the foundation of current treatment options, has raised concerns over a future of untreatable gonorrhea. Current global data on gonococcal strains suggest that several lineages, predominately characterized by mosaic penA alleles, are associated with elevated minimum inhibitory concentrations (MICs) to extended spectrum cephalosporins (ESCs). Here we report on whole genome sequences of 813 N. gonorrhoeae isolates collected through the Gonococcal Isolate Surveillance Project in the United States. Phylogenomic analysis revealed that one persisting lineage (Clade A, multi-locus sequence type [MLST] ST1901) with mosaic penA-34 alleles, contained the majority of isolates with elevated MICs to ESCs. We provide evidence that an ancestor to the globally circulating MLST ST1901 clones potentially emerged around the early to mid-20th century (1944, credibility intervals [CI]: 1935-1953), predating the introduction of cephalosporins, but coinciding with the use of penicillin. Such results indicate that drugs with novel mechanisms of action are needed as these strains continue to persist and disseminate globally.


Assuntos
Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Genes Bacterianos/genética , Neisseria gonorrhoeae/efeitos dos fármacos , Neisseria gonorrhoeae/genética , Alelos , Resistência às Cefalosporinas/efeitos dos fármacos , Resistência às Cefalosporinas/genética , Variação Genética , Genoma Bacteriano/genética , Gonorreia/epidemiologia , Gonorreia/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Neisseria gonorrhoeae/classificação , Neisseria gonorrhoeae/isolamento & purificação , Filogenia , Recombinação Genética , Análise de Sequência de DNA , Estados Unidos/epidemiologia
3.
Ecotoxicol Environ Saf ; 221: 112427, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34171688

RESUMO

Lakes in arid northwestern China, as the main pollutant-holding water bodies in the typical ecologically fragile areas, are facing the unknown risk of exposure to antibiotics and antibiotic resistance genes (ARGs). In this study, five ARGs and one mobile genetic element (intI1) and their relation with antibiotics, microbial communities and water quality were investigated in Ebinur Lake Basin, a typical salt-lake of China. Quantitative PCR analysis indicated that ARGs decreasing order in both surface water and sediment was sul1 >sul2 >tetW>ermB>qnrS, which means sulfonamide resistance genes were the main pollution ARGs. Macrolide antibiotics were the predominant antibiotics in the surface water and sediment in winter, while sulfonamides and quinolones accounted for a high proportion in summer. There was a non-corresponding relationship between ARGs and antibiotics. Moreover, the relationship between ARGs and microbial communities were defined. Sulfonamide resistance genes were carried by a greater diversity of potential host bacteria (76 genera) than other ARGs (9 genera). And their positive correlation with intI1 (p < 0.05) which promotes their migration and provides possibility of their co-occurrence in bacterial populations (e.g., Nitrospira). Bacterial genera were the main driver of ARGs distribution pattern in highly saline lake sediment. Environmental factors like salinity, total nitrogen and organic matter could have a certain influence on the occurrence of ARGs by affecting microorganisms. The results systematically show the distribution and propagation characteristics of ARGs in typical inland salt-lakes in China, and preliminarily explored the relationship between ARGs and antibiotics, resistance genes and microorganisms in lakes in ecologically fragile areas.


Assuntos
Resistência Microbiana a Medicamentos/genética , Monitoramento Ambiental , Genes Bacterianos/genética , Lagos/microbiologia , Microbiota/efeitos dos fármacos , Microbiota/genética , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , China , Quinolonas/farmacologia , Sulfonamidas/farmacologia , Qualidade da Água
4.
Huan Jing Ke Xue ; 42(6): 2937-2945, 2021 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-34032093

RESUMO

Research on the distribution of antibiotic resistance genes (ARGs) in urban sewage treatment systems is extensive, but there is still insufficient research on their abundance in industrial wastewater recycling systems. In this study, a printing and dyeing wastewater (PDWW) recycling system was constructed, and 16S rDNA and high-throughput sequencing technology was used to analyze the microbial communities and ARG abundance during the treatment process. A total of 52 ARGs in nine categories were detected, of which the relative abundance of ß-lactam resistance genes was the highest. During the treatment cycle, the concentration of aromatic pollutants increased with an increase in the number of cycles, while the abundance of ß-lactam resistance genes increased first, decreased, and then increased (reaching 61.85% on the 100th day). At the same time, the abundance of Firmicutes, Actinobacteria, and Cyanobacteria related ARGs decreased significantly (by 84.66%, 64.38%, and 85.15%, respectively). More than 21 kinds of ARGs were significantly affected by the enrichment by the aromatic pollutants. Among them, 6 kinds of ARGs were significantly positively correlated with changes in the concentrations of the aromatic pollutants (P<0.01), while 6 were significantly negatively correlate (P<0.01). These results show that the abundance of ARGs was affected by the microbial communities and the aromatic pollutants, which increased at first, decreased, and then increased during the PPDW recycling process. This study reveals the effects of the enrichment of aromatic contaminants and changes in microbial communities on ARGs during PPDW recycling, and provides theoretical guidance for the recycling of PDWW to reduce environmental pollution associated with ARGs.


Assuntos
Antibacterianos , Águas Residuárias , Antibacterianos/farmacologia , Corantes , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos/genética , Impressão Tridimensional
5.
Huan Jing Ke Xue ; 42(6): 2975-2980, 2021 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-34032097

RESUMO

Soil is the primary interface of Earth's critical zone and plays an important role in food security and sustaining environmental balance. Antibiotic resistance genes (ARGs) pose significant threat to human health and ecosystems, with croplands being intensively affected via planting patterns and the application of fertilizers. The transmission of ARGs in croplands remains largely unknown. Using high throughput quantitative Polymerase Chain Reaction (HT-qPCR) techniques, we investigated the occurrence and diversity of ARGs and their association with heavy metals in different croplands in China. A total of 187 ARGs were identified, ranging from 89 to 159 in agricultural soils. The abundance of ARGs ranged from 6.47×109 to 1.41×1010 copies·g-1 with multidrug resistance genes being the most abundant. Heavy metals including As, Co, Cr, Mo, Ni, and Pb were correlated with ARGs using the R package 'evnfit'. Furthermore, redundancy analysis (RDA) revealed that the heavy metals explained 59.3% of the variability of ARGs in the different croplands, indicating that heavy metals might exert an important influence on the composition and transmission of ARGs. Croplands soils act as a vital reservoir and reaction media for ARGs. Different crop cultivation coupled with selection pressure of heavy metals from fertilizers could have potential impacts on the prevalence, diversity, and distribution of ARGs.


Assuntos
Antibacterianos , Microbiologia do Solo , Antibacterianos/farmacologia , China , Produtos Agrícolas/genética , Resistência Microbiana a Medicamentos/genética , Ecossistema , Genes Bacterianos/genética , Humanos , Esterco , Solo
6.
Huan Jing Ke Xue ; 42(6): 2981-2991, 2021 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-34032098

RESUMO

Livestock breeding intensively uses veterinary antibiotics in concentrated feeding operations to improve growth and control disease. Consequently, livestock and poultry manure is an important repository of antibiotics and antibiotic resistance genes (ARGs). To understanding the distribution of antibiotics and ARGs in manure and surrounding soils of cattle farms in Ningxia, cattle manure from five breeding periods (lactation, calving, growing, pre-fattening, and post-fattening periods) and comparative soil samples were collected from the largest beef-breeding area in Ningxia. The compositions of ARGs in the samples were analyzed by UPLC-MS/MS and HT-qPCR. The results showed that:① Tetracycline, quinolone, and sulfonamide were the dominant antibiotics in cattle manure. The content of antibiotics in the manure varied greatly between different breeding periods. High amounts of antibiotics were detected during the pre-fattening and lactation periods, and the lowest amounts were detected during the calving period. ② Quinolone and tetracycline were the dominant antibiotics in the soils, and the detection rate and content of quinolone were highest. The cattle farms did not affect the distribution of antibiotics in the surrounding soils. The content of quinolone and tetracycline in the soils with cattle manure application were significantly higher than control and surrounding soils. ③ We detected 79-142 ARGs in cattle manure, with aminoglycosides the most common form. The number and relative abundance of ARGs were highest during the growing period and lowest during the calving period. The dominant ARGs were tetQ, ermF, and tetO-01 across all the breeding periods. ④ There were 35-79 ARGs in the tested soils, and multidrug and aminoglycoside ARGs were dominant. The cattle farms did not affect the number and relative abundance of ARGs in the surrounding soils; however, manure application significantly affected the number and relative abundance of ARGs. ⑤ Sulfonamide and chloramphenicol ARGs are at risk of mobilization and horizontal transport. A correlation analysis showed that the relative abundances of aminoglycoside and tetracycline in cattle manure were significantly positively correlated with their contents. ⑥ Aminoglycoside, sulfonamide, chloramphenicol, and mobile genetic elements (MGEs) in manure were significantly or extremely significantly positively correlated with aminoglycosides and sulfonamides in the soils, whereas macrolides were negatively correlated with vancomycin. These results provide baseline data to inform controls on the variety and dosages of feed and veterinary drugs in cattle farms and the application of organic fertilizers in agriculture.


Assuntos
Esterco , Solo , Animais , Antibacterianos/farmacologia , Bovinos , Cromatografia Líquida , Resistência Microbiana a Medicamentos , Fazendas , Genes Bacterianos/genética , Microbiologia do Solo , Espectrometria de Massas em Tandem
7.
Huan Jing Ke Xue ; 42(6): 2992-2999, 2021 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-34032099

RESUMO

To investigate the effects of temperature and stirring on antibiotic resistance genes (ARGs) and microbial communities during the anaerobic digestion of dairy manure, mesophilic and thermophilic anaerobic digestion experiments were performed with and without stirring. Two-way analysis of variance indicated that temperature affected biogas production more strongly than stirring (η2=0.934>0.911), and thermophilic and stirring increased the total biogas yield by 13.93% and 12.63%, respectively. The effect of temperature on the removal of ARGs was also stronger than that of stirring (η2=0.992>0.920), where thermophilic conditions enhanced the reduction of ARGs and MGEs to 0.09-1.53 (logarithm), while stirring had no significant effects. When temperature was altered from mesophilic to thermophilic, the microbial communities shifted, with Firmicutes becoming the dominant phylum after thermophilic anaerobic digestion, with a relative abundance of >86%. Network analysis demonstrated that eight genera including Sedimentibacter, Sphaerochaeta, and Pseudomonas were the hosts of ARGs and MGEs, and the redundancy analysis suggested that physicochemical parameters play important roles in shaping microbial communities, especially TAN and TVFAs, which indirectly affected the ARGs by altering their host bacteria.


Assuntos
Esterco , Microbiota , Anaerobiose , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos/genética , Microbiota/genética , Temperatura
8.
Nat Commun ; 12(1): 2653, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976161

RESUMO

Plasmid persistence in bacterial populations is strongly influenced by the fitness effects associated with plasmid carriage. However, plasmid fitness effects in wild-type bacterial hosts remain largely unexplored. In this study, we determined the fitness effects of the major antibiotic resistance plasmid pOXA-48_K8 in wild-type, ecologically compatible enterobacterial isolates from the human gut microbiota. Our results show that although pOXA-48_K8 produced an overall reduction in bacterial fitness, it produced small effects in most bacterial hosts, and even beneficial effects in several isolates. Moreover, genomic results showed a link between pOXA-48_K8 fitness effects and bacterial phylogeny, helping to explain plasmid epidemiology. Incorporating our fitness results into a simple population dynamics model revealed a new set of conditions for plasmid stability in bacterial communities, with plasmid persistence increasing with bacterial diversity and becoming less dependent on conjugation. These results help to explain the high prevalence of plasmids in the greatly diverse natural microbial communities.


Assuntos
Bactérias/genética , Transferência Genética Horizontal , Genes Bacterianos/genética , Variação Genética , Genoma Bacteriano/genética , Plasmídeos/genética , Algoritmos , Antibacterianos/farmacologia , Bactérias/classificação , Farmacorresistência Bacteriana Múltipla/genética , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Microbioma Gastrointestinal/genética , Humanos , Microbiota/genética , Filogenia , Especificidade da Espécie
9.
Biomed Res Int ; 2021: 5568845, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33981770

RESUMO

The flora compositions of nitrogen-fixing bacteria in roots of Pennisetum giganteum z.x.lin at different growth stages and the expression and copy number of nitrogen-fixing gene nifH were studied by Illumina Miseq second-generation sequencing technology and qRT-PCR. The results showed that there were more than 40,000~50,000 effective sequences in 5 samples from the roots of P. giganteum, with Proteobacteria and Cyanobacteria as the dominant nitrogen-fixing bacteria based on the OTU species annotations for each sample and Bradyrhizobium as the core bacterial genera. The relative expression and quantitative change of nifH gene in roots of P. giganteum at different growth stages were consistent with the changes in the flora compositions of nitrogen-fixing microbia. Both revealed a changing trend with an initial increase and a sequential decrease, as well as changing order as jointing stage>maturation stage>tillering stage>seedling stage>dying stage. The relative expression and copy number of nifH gene were different in different growth stages, and the difference among groups basically reached a significant level (p < 0.05). The relative expression and copy number of nifH gene at the jointing stage were the highest, and the 2-△△CT value was 4.43 folds higher than that at the seedling stage, with a copy number of 1.32 × 107/g. While at the dying stage, it was the lowest, and the 2-△△CT value was 0.67 folds, with a copy number of 0.31 × 107/g.


Assuntos
Proteínas de Bactérias , Bactérias Fixadoras de Nitrogênio , Oxirredutases , Pennisetum/microbiologia , Raízes de Plantas/microbiologia , Proteínas de Bactérias/análise , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Dosagem de Genes/genética , Genes Bacterianos/genética , Bactérias Fixadoras de Nitrogênio/classificação , Bactérias Fixadoras de Nitrogênio/genética , Bactérias Fixadoras de Nitrogênio/metabolismo , Oxirredutases/análise , Oxirredutases/genética , Oxirredutases/metabolismo , Microbiologia do Solo
10.
Nat Commun ; 12(1): 2213, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33850115

RESUMO

Global oceanographic monitoring initiatives originally measured abiotic essential ocean variables but are currently incorporating biological and metagenomic sampling programs. There is, however, a large knowledge gap on how to infer bacterial functions, the information sought by biogeochemists, ecologists, and modelers, from the bacterial taxonomic information (produced by bacterial marker gene surveys). Here, we provide a correlative understanding of how a bacterial marker gene (16S rRNA) can be used to infer latitudinal trends for metabolic pathways in global monitoring campaigns. From a transect spanning 7000 km in the South Pacific Ocean we infer ten metabolic pathways from 16S rRNA gene sequences and 11 corresponding metagenome samples, which relate to metabolic processes of primary productivity, temperature-regulated thermodynamic effects, coping strategies for nutrient limitation, energy metabolism, and organic matter degradation. This study demonstrates that low-cost, high-throughput bacterial marker gene data, can be used to infer shifts in the metabolic strategies at the community scale.


Assuntos
Bactérias/genética , Genes Bacterianos/genética , Redes e Vias Metabólicas/genética , Metagenômica/métodos , Bactérias/classificação , Fenômenos Fisiológicos Bacterianos , Biodiversidade , Ecologia , Metagenoma , Oceano Pacífico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Termodinâmica
11.
Int J Mol Sci ; 22(9)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33926096

RESUMO

The SOS response is induced upon DNA damage and the inhibition of Z ring formation by the product of the sulA gene, which is one of the LexA-regulated genes, allows time for repair of damaged DNA. On the other hand, severely DNA-damaged cells are eliminated from cell populations. Overexpression of sulA leads to cell lysis, suggesting SulA eliminates cells with unrepaired damaged DNA. Transcriptome analysis revealed that overexpression of sulA leads to up-regulation of numerous genes, including soxS. Deletion of soxS markedly reduced the extent of cell lysis by sulA overexpression and soxS overexpression alone led to cell lysis. Further experiments on the SoxS regulon suggested that LpxC is a main player downstream from SoxS. These findings suggested the SulA-dependent cell lysis (SDCL) cascade as follows: SulA→SoxS→LpxC. Other tests showed that the SDCL cascade pathway does not overlap with the apoptosis-like and mazEF cell death pathways.


Assuntos
Dano ao DNA/fisiologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Amidoidrolases/metabolismo , Apoptose/genética , Proteínas de Bactérias/metabolismo , Divisão Celular/genética , Dano ao DNA/genética , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/genética , Genes Bacterianos/genética , Serina Endopeptidases/metabolismo , Transativadores/metabolismo
12.
Nat Commun ; 12(1): 2435, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33893312

RESUMO

Antibiotic resistance spreads among bacteria through horizontal transfer of antibiotic resistance genes (ARGs). Here, we set out to determine predictive features of ARG transfer among bacterial clades. We use a statistical framework to identify putative horizontally transferred ARGs and the groups of bacteria that disseminate them. We identify 152 gene exchange networks containing 22,963 bacterial genomes. Analysis of ARG-surrounding sequences identify genes encoding putative mobilisation elements such as transposases and integrases that may be involved in gene transfer between genomes. Certain ARGs appear to be frequently mobilised by different mobile genetic elements. We characterise the phylogenetic reach of these mobilisation elements to predict the potential future dissemination of known ARGs. Using a separate database with 472,798 genomes from Streptococcaceae, Staphylococcaceae and Enterobacteriaceae, we confirm 34 of 94 predicted mobilisations. We explore transfer barriers beyond mobilisation and show experimentally that physiological constraints of the host can explain why specific genes are largely confined to Gram-negative bacteria although their mobile elements support dissemination to Gram-positive bacteria. Our approach may potentially enable better risk assessment of future resistance gene dissemination.


Assuntos
Antibacterianos/farmacologia , Bactérias/genética , Farmacorresistência Bacteriana/genética , Transferência Genética Horizontal/genética , Genes Bacterianos/genética , Genoma Bacteriano/genética , Bactérias/classificação , Filogenia , Especificidade da Espécie
13.
J Environ Manage ; 289: 112576, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33865023

RESUMO

The increasing prevalence of antibiotic resistance genes (ARGs) in the soil environment poses a serious threat to crop safety and even public health. In this study, the fate of ARGs in the soil was investigated during the growth period of pakchoi and after harvesting with the application of different kinds of fertilizers. The result showed that increasing rate of soil ARGs during the growth period of pakchoi followed the order of composted manure > commercial fertilizer > mineral fertilizer. After harvesting, soil ARGs abundance treated with mineral fertilizer, commercial fertilizer or composted manure significantly increased by 0.63, 3.19 and 8.65 times (p < 0.05), respectively, compared with the non-fertilized soil. The ARGs abundance in the pakchoi treated with composted manure was significantly higher than that of treatments with mineral fertilizer and commercial organic fertilizer. These findings indicated the application of composted pig manure would significantly increase the pollution load of ARGs in farmland soil and plant, and also promote the proliferation of farmland ARGs. Principal component analysis suggested that bacterial communities might have a significant influence on ARGs changes during the growth period of pakchoi. Network analysis further indicated ARGs changes may be mainly related to their host bacteria (including Gammaproteobacteria, Flavobacteriia and Bacilli). The results provided a proper method and useful information on reducing transmission risk of ARGs and control the propagation of ARGs in agricultural activities.


Assuntos
Fertilizantes , Solo , Animais , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Fazendas , Fertilizantes/análise , Genes Bacterianos/genética , Esterco , Microbiologia do Solo , Suínos
14.
Huan Jing Ke Xue ; 42(5): 2413-2421, 2021 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-33884812

RESUMO

The organic fraction of municipal solid waste (OFMSW) has become one of the sources and reservoirs of antibiotic resistance genes (ARGs). It is essential to explore the fate of ARGs during biological treatment of OFMSW. Therefore, the changes in several types of ARGs and integron genes during anaerobic digestion of the OFMSW were analyzed by quantitative PCR. Furthermore, the effects of different particle sizes of activated carbon on the behaviors of the target genes and the potential microbial mechanisms of ARGs dynamics were investigated. The results showed that the total ARGs in the initial system were reduced after anaerobic digestion with or without the presence of activated carbon. The removal rate of the absolute abundance of total ARGs was 29.95%-63.40%. In the final system of anaerobic digestion of the OFMSW, the abundance of total ARGs in powdered activated carbon (PAC) groups was significantly higher than that in the control group (P<0.05). The supplementation of PAC inhibited the reduction of ARGs, and the supplementation of granular activated carbon had no significant effect on the change in ARGs. The potential host bacteria of ARGs were mainly Clostridia, Bacteroidia, and Synergistia during anaerobic digestion. The enrichment of host bacteria caused by PAC addition was the main reason for the increase in the target genes. Moreover, Clostridia might have been the main driving factor for the growth and decline of ARGs. These results will help us to understand the dissemination of ARGs and the impacts of activated carbon addition on ARGs during anaerobic digestion of the OFMSW.


Assuntos
Antibacterianos , Resíduos Sólidos , Anaerobiose , Antibacterianos/farmacologia , Carvão Vegetal , Resistência Microbiana a Medicamentos , Genes Bacterianos/genética
15.
Huan Jing Ke Xue ; 42(5): 2541-2549, 2021 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-33884825

RESUMO

The widespread use of antibiotics in the aquaculture industry has caused antibiotic resistance genes (ARGs) pollution. Metagenomics technology was used to detect and analyze the relative abundance of ARGs and microbial community structure in a fishery reclamation mining subsidence area. A total of 29 ARGs were detected, and bacA had the highest relative abundance in all the samples, reaching 1.96×10-5-1.19×10-4. The relative abundance of sulfonamide and tetracycline ARGs in sediments was relatively high and the relative abundance of multidrug ARGs in well water was relatively high. Proteobacteria was the most dominant bacterial phylum in all the samples, and Chloroflexi and Euryarchaeota were relatively abundant in the sediments. Thiobacillus was the most dominant bacterial genus in the sediments, and Acinetobacter and Pseudomonas were the dominant bacterial genera in the well water. The correlation analysis between the ARGs and microorganisms showed that the genera and ARGs were mainly correlated to a moderate degree, and multiple genera had significant positive correlations with ARGs. The distribution of ARGs was affected by the structure of the microbial community. The sediments and well water in the fishery reclamation mining subsidence area were both contaminated by ARGs, and corresponding control measures should be strengthened to protect the regional environment.


Assuntos
Antibacterianos , Microbiota , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Pesqueiros , Genes Bacterianos/genética , Microbiota/genética
16.
Microbiome ; 9(1): 81, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795006

RESUMO

BACKGROUND: Research is needed to delineate the relative and combined effects of different antibiotic administration and manure management practices in either amplifying or attenuating the potential for antibiotic resistance to spread. Here, we carried out a comprehensive parallel examination of the effects of small-scale (> 55 °C × 3 days) static and turned composting of manures from dairy and beef cattle collected during standard antibiotic administration (cephapirin/pirlimycin or sulfamethazine/chlortetracycline/tylosin, respectively), versus from untreated cattle, on "resistomes" (total antibiotic resistance genes (ARGs) determined via shotgun metagenomic sequencing), bacterial microbiota, and indicator ARGs enumerated via quantitative polymerase chain reaction. To gain insight into the role of the thermophilic phase, compost was also externally heated to > 55 °C × 15 days. RESULTS: Progression of composting with time and succession of the corresponding bacterial microbiota was the overarching driver of the resistome composition (ANOSIM; R = 0.424, p = 0.001, respectively) in all composts at the small-scale. Reduction in relative abundance (16S rRNA gene normalized) of total ARGs in finished compost (day 42) versus day 0 was noted across all conditions (ANOSIM; R = 0.728, p = 0.001), except when externally heated. Sul1, intI1, beta-lactam ARGs, and plasmid-associated genes increased in all finished composts as compared with the initial condition. External heating more effectively reduced certain clinically relevant ARGs (blaOXA, blaCARB), fecal coliforms, and resistome risk scores, which take into account putative pathogen annotations. When manure was collected during antibiotic administration, taxonomic composition of the compost was distinct according to nonmetric multidimensional analysis and tet(W) decayed faster in the dairy manure with antibiotic condition and slower in the beef manure with antibiotic condition. CONCLUSIONS: This comprehensive, integrated study revealed that composting had a dominant effect on corresponding resistome composition, while little difference was noted as a function of collecting manure during antibiotic administration. Reduction in total ARGs, tet(W), and resistome risk suggested that composting reduced some potential for antibiotic resistance to spread, but the increase and persistence of other indicators of antibiotic resistance were concerning. Results indicate that composting guidelines intended for pathogen reduction do not necessarily provide a comprehensive barrier to ARGs or their mobility prior to land application and additional mitigation measures should be considered. Video Abstract.


Assuntos
Compostagem , Esterco , Animais , Antibacterianos/farmacologia , Bovinos , Resistência Microbiana a Medicamentos , Genes Bacterianos/genética , RNA Ribossômico 16S/genética , Solo
17.
Huan Jing Ke Xue ; 42(2): 749-760, 2021 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742869

RESUMO

Emerging contaminants including antibiotics and antibiotic resistance genes (ARGs) have been frequently detected in drinking water resources. In this study, the occurrence of antibiotics and ARGs in various environmental matrices in representative drinking water sources in Jiangsu Province and their influencing factors were explored. Five representative drinking water sources in northern, central, and southern Jiangsu were selected. Water, surface sediment, and epilithic biofilm samples were harvested near the water intakes of each water resource in December 2018 and June 2019. The concentrations and abundances of ten antibiotics, one integrase gene intl1, and seven common ARGs were measured. The results suggest that the concentrations of the target antibiotics and ARGs are relatively low compared to previously reported data in China and elsewhere in the world. The target antibiotics were detected in all of the water sources. The concentrations of sulfonamides in the water, surface sediment, and epilithic biofilm ranged from not found (NF) to 37.4 ng·L-1, NF to 47.3 ng·g-1, and NF to 3759.1 ng·g-1, respectively; the concentrations of quinolones in three matrices were NF-5.3 ng·L-1, 0.4-32.5 ng·g-1, and NF-4220.9 ng·g-1, respectively. The detection rates of the ARGs including sul 1, sul2, tetW, and tetQ were 100%, among which the sulfonamides sul1 and sul2 showed the highest abundance. The absolute abundances of sul1 in the three matrices were 2.48×106 copies·L-1, 3.54×107 copies·g-1, and 1.44×109 copies·g-1, respectively. The abundances of ARGs in the sediments and epilithic biofilms were comparable, and were much higher than in the water body. The phyla Bacteroidetes, Proteobacteris, Firmicutes, Verrucobacteria, and Actinomycetes have proven potential hosts for ARGs and might play an important role in the transmission and diffusion of resistance genes. This study offers baseline information on the presence of antibiotics and ARGs in the drinking water sources of Jiangsu Province, providing a significant theoretical basis for ARGs pollution control and safety guidelines for drinking water resources.


Assuntos
Antibacterianos , Água Potável , Antibacterianos/análise , China , Água Potável/análise , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos/genética , Recursos Hídricos
18.
Huan Jing Ke Xue ; 42(2): 761-765, 2021 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742870

RESUMO

Antibiotic resistance genes (ARGs) are considered emerging contaminants posing an increasing threat to the ecological environment and global human health. Profiling ARGs in tailings ponds is essential to better understand their spatial and temporal dynamics. In this study, high-throughput quantitative polymerase chain reaction (PCR) techniques were used to investigate the occurrence, diversity, abundance, and distribution of ARGs in a tailings pond. A total of 97, 52, 44, and 56 ARGs were detected in WK0, WK1, WK2, and HS, respectively, with 11, 6, 3, and 6 mobile genetic elements (MGEs) also being detected, respectively. The absolute abundance of ARGs in the pond water ranged from 6.39×107 to 1.75×108 copies·L-1. Additionally, the abundance of MGEs were higher than ARGs in WK1 and WK2, indicating the potential for horizontal gene transfer (HGT). Furthermore, Cu, TOC, and MGEs were significantly associated with ARGs. Indeed, redundancy analysis (RDA) revealed that Cu, TOC, and MGEs explained 61.64% of the alteration of the ARG profiles, implying their potential roles in the spread and evolution of ARGs in tailings ponds.


Assuntos
Antibacterianos , Lagoas , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos/genética , Humanos
19.
Poult Sci ; 100(4): 100985, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33647720

RESUMO

Bacterial infections of yolk sacs contribute to increased mortality of chicks, chronic infections during their rearing, or increased selection in the flock, which in turn leads to high economic losses in poultry production worldwide. The aim of this study was a phenotypic and genotypic characterization of enterococci isolated from yolk sac infections (YSI) of broiler chickens from Poland and the Netherlands. Biochemical, matrix-assisted laser desorption/ionization (MALDI)-time-of-flight (TOF) MS, and rpoA gene sequencing identification was performed. Moreover, phenotypic and genotypic characterization of virulence factors and analysis of the clonal relationship of isolates by MALDI-TOF MS and enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) were performed. The biochemical test identified 70 isolates as Enterococcus faecalis and 6 as Enterococcus mundtii. The results of MALDI-TOF MS were 100% concordant with those obtained by rpoA gene sequencing, and all 76 isolates were identified as E. faecalis. Differences were noted in the ß-glucuronidase, ß-glucosidase, α-galactosidase, phosphatase, melibiose, lactose, and raffinose tests that is going about the results of biochemical identification. None of the isolates were beta-hemolytic on blood agar in aerobic conditions, but all but one were gelatinase positive. Among biofilm-forming isolates (30/76; 39.5%), as many as 66.7% (20/30) were Polish E. faecalis strains. Most of the isolates carried virulence genes, that is gelE, ace, asa1, efaAfs, fsrA, fsrB, fsrC, cob, cpd, and ccf, but none had the hyl gene. Some isolates harbored cyl operon genes. One Polish strain (ST16) had all of the tested cyl genes and the esp gene, considered clinically important, and showed the highest biofilm-forming ability. Nearly 50% of the isolates showed close genetic relatedness in ERIC typing. In contrast with MALDI-TOF MS cluster analysis, ERIC-PCR results did not show a relationship with the origin of the strains. Using MALDI-TOF MS, 7 peaks were found in Polish and Dutch isolates, which may type them as species-specific biomarkers in E. faecalis from YSI.


Assuntos
Enterococcus , Infecções por Bactérias Gram-Positivas , Doenças das Aves Domésticas , Fatores de Virulência , Saco Vitelino , Animais , Galinhas , Enterococcus/genética , Enterococcus/patogenicidade , Genes Bacterianos/genética , Genótipo , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/veterinária , Países Baixos , Fenótipo , Polônia , Doenças das Aves Domésticas/microbiologia , Fatores de Virulência/genética , Saco Vitelino/microbiologia
20.
Arch Virol ; 166(5): 1337-1344, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33683473

RESUMO

A reservoir of antibiotic resistance genes (ARGs) is present in pathogenic, commensal, and environmental bacteria as well as in mobile genetic elements, including bacteriophages. Wastewater treatment plants (WWTPs) are considered hotspots for the spread of ARGs. The aim of this work was to analyze the diversity of the highly prevalent ARGs blaCTX-M and blaTEM in bacterial and bacteriophage fractions associated with human and animal environments through the study of urban waste and animal residues discharged into WWTPs to provide information about the composition and maintenance of the current resistome in Buenos Aires, Argentina. The results showed that a putative extended-spectrum variant of the blaTEM gene was the most frequently detected, with blaTEM-116 being the most prevalent, while a recently described type, blaTEM-229, was also found. In the bacteriophage fraction, we detected blaCTX-M genes from four out of the five clusters described. The detection of blaCTX- M-9-like and blaCTX-M-25-like genes was unexpected based on surveys of the ARGs from clinical pathogens circulating regionally. The finding of divergent blaCTX-M sequences associated with previously reported environmental genes argues in favor of the natural environment as a reservoir of resistance genes. ARGs were detected in bacteriophages as frequently as in bacterial communities, and furthermore, the blaCTX-M genes were more diverse in the bacteriophage fraction. Bacteriophages might therefore play a role in the spread of ARGs in the environment, but they might also be used as "reporters" for monitoring circulating ARGs.


Assuntos
Bacteriófagos/genética , Águas Residuárias/virologia , beta-Lactamases/genética , Animais , Argentina , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos/genética , Genes Virais/genética , Variação Genética , Humanos , Filogenia , Águas Residuárias/microbiologia , beta-Lactamases/classificação
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