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1.
J Hazard Mater ; 416: 125847, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492800

RESUMO

Microplastics (MPs) and antibiotic resistance genes (ARGs) are two classes of emerging and prevalent contaminants in terrestrial environments. To date, effects of MPs on the occurrence of ARGs in terrestrial invertebrates remain uncertain. Here we exposed earthworms to a soil amended with polystyrene MPs at two environmentally relevant concentrations to elucidate the occurrence and mechanisms of ARGs in earthworms impacted by MPs with different sizes. Nano-size and 10 mg/kg of 100 µm MPs slightly affected the occurrence of ARGs in earthworms. Highest abundance of ARGs was found in the presence of 10 mg/kg of 10 µm MPs, whereas 100 mg/kg of 10 µm MPs significantly changed the profile of ARGs. Metagenomics sequencing and toxicity tests indicated that MPs caused toxicity and influenced the abundance of microbial community in earthworms, resulting in the changes of ARGs. Results of proteomics and metabolomics demonstrated that 100 mg/kg of 10 µm MPs changed the microenvironment of earthworm gut, built a new homeostatic process, and thus increased the abundance of key bacterial that carried a variety of ARGs. This study highlights the size-dependent toxic effects of MPs and their impacts on the transfer of ARGs in terrestrial environments.


Assuntos
Microplásticos , Oligoquetos , Animais , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Genes Bacterianos , Oligoquetos/genética , Plásticos , Poliestirenos , Solo
2.
J Hazard Mater ; 416: 125865, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492813

RESUMO

Anaerobic biological treatment technologies are one of the major hotspots of antibiotic resistance genes (ARGs). Previous studies have applied the electrochemical process to improve biogas production, however, it was challenged that high voltages might promote membrane permeability and reactive oxygen species overproduction to promote ARGs proliferation. Herein, the biogas production and ARGs proliferation in an anaerobic electrochemical membrane bioreactor (AnEMBR) were investigated at the gradient voltages of 0-0.9 V. Results show the reactor performances (average CH4 production and current generation) were distinctly improved with the increase of applied voltage, and reached the optimum at 0.9 V. However, long-term application (>30 day) of 0.9 V deteriorated the reactor performances. Meanwhile, the relative abundances of most target ARGs in the supernatant and effluent of AnEMBR at 0.9 V increased by 0.68-1.55 and 0.42-1.26 logs compared to those before applying voltage, respectively. After disconnecting the circuit, these ARGs abundances all decreased to the original level. Significant correlations between intlI and ARGs (e.g., tetA, tetQ, sulI, and sulII) were observed, indicating horizontal gene transfer may contribute to the increased ARGs. Moreover, the shift of microbial communities caused by the applied voltage enriched potential ARGs-hosts (e.g., Tolumonas), contributing to the proliferation of ARGs.


Assuntos
Antibacterianos , Biocombustíveis , Anaerobiose , Antibacterianos/farmacologia , Reatores Biológicos , Proliferação de Células , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos
3.
J Hazard Mater ; 416: 125868, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492815

RESUMO

Comprehensive studies on the effects of cold stress on antibiotic resistance genes (ARGs) in the intestines and feces remain scarce. In this study, pigs were selected as the animal model and divided into a normal temperature group and a 48-h short-term cold stress group. The ARG profiles in fecal, cecal content and cecal mucosa samples were analyzed. The results showed that the normalized abundance of ARGs in the cecal mucosa samples in the cold stress group was significantly higher than that in the normal temperature group, while the normalized ARG abundances in the fecal and cecal content samples were significantly lower than those in the normal temperature group (P < 0.05). The bacterial community composition (especially Firmicutes) was the major driver impacting the ARG profile and accounted for 32.2% of the variation in the ARG profile, followed by metabolites (especially creatinine and oxypurinol) and mobile genetic elements (MGEs) (especially plasmids and insertion elements). And it was found that creatinine and oxypurinol can reduce the abundance of ARGs and Firmicutes in the in vitro experiment. The results indicate that short-term cold stress can reduce the abundance of ARGs in the cecum and feces of pigs, providing reference data for environmental safety.


Assuntos
Antibacterianos , Genes Bacterianos , Animais , Antibacterianos/farmacologia , Ceco , Resposta ao Choque Frio , Resistência Microbiana a Medicamentos/genética , Fezes , Suínos
4.
Water Res ; 203: 117507, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34392041

RESUMO

In recent years, karst water has been polluted by emerging pollutants such as antibiotics. In this study, the bacterial communities and antibiotic resistance genes (ARGs) in antibiotics contaminated karst river was studied in summer and winter. The concentration of antibiotics in winter karst river is higher than that in summer, and there are significant differences in structure of bacterial community and ARGs between karst river water samples. Aminoglycoside, beta-lactamase and multidrug are the main types of ARGs, and transposons play an important role in the spread of ARGs. The horizontal gene transfer (HGT) of ARGs between bacteria mediated by mobile genetic elements (MGEs) would cause the spread of ARGs and bring potential ecological risks. In addition, we found that the risk of antibiotic resistant pathogenic bacteria (ARPB) in winter was possibly higher than that in summer. It was suggested that the discharge of antibiotics, water amount and seasonal occurrence time of human intestinal diseases affect the risks caused by antibiotics contaminants. This study helps us to understand the transmission mechanism of ARGs and their potential seasonal ecological risks in complex karst water systems.


Assuntos
Antibacterianos , Rios , Antibacterianos/farmacologia , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Humanos
5.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445146

RESUMO

Ehrlichia chaffeensis causes human monocytic ehrlichiosis. Little is known about how this and other related tick-borne rickettsia pathogens maintain pH homeostasis in acidified phagosomes and the extracellular milieu. The membrane-bound sodium (cation)/proton antiporters are found in a wide range of organisms aiding pH homeostasis. We recently reported a mutation in an antiporter gene of E. chaffeensis (ECH_0379) which causes bacterial in vivo attenuation. The E. chaffeensis genome contains 10 protein coding sequences encoding for predicted antiporters. We report here that nine of these genes are transcribed during the bacterial growth in macrophages and tick cells. All E. chaffeensis antiporter genes functionally complemented antiporter deficient Escherichia coli. Antiporter activity for all predicted E. chaffeensis genes was observed at pH 5.5, while gene products of ECH_0179 and ECH_0379 were also active at pH 8.0, and ECH_0179 protein was complemented at pH 7.0. The antiporter activity was independently verified for the ECH_0379 protein by proteoliposome diffusion analysis. This is the first description of antiporters in E. chaffeensis and demonstrates that the pathogen contains multiple antiporters with varying biological functions, which are likely important for the pH homeostasis of the pathogen's replicating and infectious forms.


Assuntos
Antiporters/genética , Bactérias/genética , Proteínas de Bactérias/genética , Ehrlichia chaffeensis/genética , Genes Bacterianos/genética , Homeostase/genética , Sódio/metabolismo , Escherichia coli/genética , Concentração de Íons de Hidrogênio , Macrófagos/metabolismo , Mutação/genética , Prótons
6.
Nucleic Acids Res ; 49(15): 8757-8776, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34379789

RESUMO

As compared to eukaryotes, bacteria have a reduced tRNA gene set encoding between 30 and 220 tRNAs. Although in most bacterial phyla tRNA genes are dispersed in the genome, many species from distinct phyla also show genes forming arrays. Here, we show that two types of arrays with distinct evolutionary origins exist. This work focuses on long tRNA gene arrays (L-arrays) that encompass up to 43 genes, which disseminate by horizontal gene transfer and contribute supernumerary tRNA genes to the host. Although in the few cases previously studied these arrays were reported to be poorly transcribed, here we show that the L-array of the model cyanobacterium Anabaena sp. PCC 7120, encoding 23 functional tRNAs, is largely induced upon impairment of the translation machinery. The cellular response to this challenge involves a global reprogramming of the transcriptome in two phases. tRNAs encoded in the array are induced in the second phase of the response, directly contributing to cell survival. Results presented here show that in some bacteria the tRNA gene set may be partitioned between a housekeeping subset, which constantly sustains translation, and an inducible subset that is generally silent but can provide functionality under particular conditions.


Assuntos
Genes Bacterianos , Óperon , Biossíntese de Proteínas , RNA de Transferência/genética , Estresse Fisiológico/genética , Anabaena/genética , Antibacterianos/farmacologia , Regulação Bacteriana da Expressão Gênica , Genoma Bacteriano , Viabilidade Microbiana/genética , RNA de Transferência/metabolismo , Sequências Reguladoras de Ácido Nucleico
7.
Water Res ; 203: 117533, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34416649

RESUMO

Studies to understand the role wastewater treatment plants (WWTPs) play in the dissemination of antibiotics (ABs), and in the emergence of antibiotic resistance (ABR), play an important role in tackling this global crisis. Here we describe the abundance and distribution of 16 ABs, and 4 corresponding antibiotic resistance genes (ARGs), sampled from the influent to five WWTPs within a single river catchment. We consider four classes of antibiotics: fluroquinolones, macrolides, sulfamethoxazole and chloramphenicol, as well the corresponding antibiotic resistance genes qnrS, ermB, sul1 and catA. All antibiotics, apart from four fluroquinolones (besifloxacin, lomefloxacin, ulifloxacin, prulifloxacin), were detected within all influent wastewater from the 5 cities (1 city = 1 WWTP), as were the corresponding antibiotic resistance genes (ARGs). Strong correlations were observed between the daily loads of ABs and ARGs versus the size of the population served by each WWTP, as well as between AB and ARG loads at a single site. The efficiency of ABs and ARGs removal by the WWTPs varied according to site (and treatment process utilized) and target, although strong correlations were maintained between the population size served by WWTPs and daily loads of discharged ABs and ARGs into the environment. We therefore conclude that population size is the main determinant of the magnitude of AB and ARG burden in the environment.


Assuntos
Antibacterianos , Rios , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Humanos , Águas Residuárias/análise
8.
Bioresour Technol ; 340: 125742, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34426239

RESUMO

In this study, six strains belonging to Alcaligenes, Enterobacter and Bacillus were employed to enhance the composting process of biogas residues and agricultural wastes. The dynamic changes of dissolved organic matter (DOM), microbial community and functional genes in composting was monitored. It was found bioaugmentation reduced the content of lignocellulose in the compost by 27.14-66.30%, and increased the seed germination index (GI) of the compost by 37.59%. Metagenomics analysis of the composting process indicated Proteobacteria (35.38%-64.19%), Actinobacteria (11.24%-28.93%) and Bacteroidetes (3.65%-9.57%) are the dominant microorganisms during the bioaugmented composting. The abundance of genes associated with glycoside hydrolase was obviously enhanced and the antibiotic resistance genes (ARGs) was significantly reduced during the bioaugmented composting. Following nursery investigation indicated the seedling substrates composed of bioaugmented compost increased the dry weight of tomato seedlings by 1.7 times, revealing obvious large-scale application potential in the resource utilization of agricultural wastes.


Assuntos
Compostagem , Antibacterianos/farmacologia , Biocombustíveis , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Lignina , Esterco , Solo
9.
Environ Pollut ; 287: 117651, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34426396

RESUMO

Antibiotic resistance in aquatic ecosystems presents an environmental health issue worldwide. Urban recipient water quality is susceptible to effluent discharges with antibiotic resistance contaminants and needs to be protected, particularly for those as sources of drinking water production. Knowledge on aquatic resistome profiles in downstream of wastewater treatment plants allows a better understanding of the extent to which antibiotic resistance contaminants emerge and spread in recipient waters, but such information remains very limited in Sweden. The key objective of this study was to determine the resistome profiles of numerous antibiotic resistance genes (ARGs), mobile genetic elements (MGEs) and other genes in urban recipient water systems connected to Sweden's major drinking water reservoir. This was achieved through analysis of surface water samples for 296 genes using high-throughput quantitative PCR arrays. A total of 167 genes were detected in at least one of the samples, including 150 ARGs conferring resistance to 11 classes of antibiotics, 7 integrase MGEs and 9 other genes. There was a spatial difference in the resistome profiles with the greatest average relative abundance of resistance genes observed in the water body of Västerås followed by Uppsala, Stockholm and Eskilstuna, as similar to the general pattern of the antibiotic sales for these regions. ARGs against ß-lactams and sulfonamides showed the highest average relative abundance in the studied water bodies, while vancomycin resistance genes were only found in the Uppsala water environment. Generally, the recipient water bodies were detected with higher numbers of genes and greater relative abundances as compared to the upstream sites. Anthropogenic pollution, i.e., wastewater discharge, in the recipient water was also reflected by the finding of intI, sul1 and crAssphage. Overall, this study provided the first quantitative assessment of aquatic environmental resistomes in Sweden, highlighting the widespread of antibiotic resistance contaminants in urban recipient waters.


Assuntos
Antibacterianos , Genes Bacterianos , Ecossistema , Reação em Cadeia da Polimerase , Suécia , Águas Residuárias
10.
Artigo em Inglês | MEDLINE | ID: mdl-34427555

RESUMO

Currently, Lactococcus garvieae contains two subspecies: L. garvieae subsp. bovis and L. garvieae subsp. garvieae. In a study by Varsha and Nampoothiri, high pheS (99.7 %) and rpoA (99.6 %) sequence similarities indicated that L. garvieae subsp. bovis and Lactococcus formosensis probably have a close taxonomic relationship; low pheS (92.2 %) and rpoA (97.8 %) sequence similarities and relatively low DNA-DNA hybridization value (75.8 %) indicated that L. garvieae subsp. bovis and L. garvieae subsp. garvieae probably represent two different species. In the present study, the taxonomic relationships between L. garvieae subsp. bovis, L. garvieae subsp. garvieae and L. formosensis were re-examined based on sequence analyses of 16S rRNA, pheS, recA, rpoA and rpoB genes, average nucleotide identity (ANI), digital DNA-DNA hybridization (dDDH) values, average amino acid identity (AAI), fatty acid methyl ester analysis and phenotypic characterization. L. garvieae subsp. bovis LMG 30663T exhibited 97.3 % ANI, 78.3 % dDDH and 96.4 % AAI values to L. formosensis NBRC 109475T, higher than the threshold for species demarcation (95-96, 70 and 95-96 %, respectively), indicating that L. garvieae subsp. bovis LMG 30663T and L. formosensis NBRC 109475T belong to the same species. L. garvieae subsp. bovis LMG 30663T had 91.2 % ANI, 43.3 % dDDH and 92.9-93.0% AAI values with the type strain of L. garvieae subsp. garvieae, indicating that they represent two different species. Because L. formosensis has been proposed and validated before L. garvieae subsp. bovis, L. garvieae subsp. bovis is transferred to L. formosensis as L. formosensis subsp. bovis comb. nov. The type strain of L. formosensis subsp. bovis is BSN307T (=DSM 100577T=MCC 2824T=KCTC 21083T=LMG 30663T). The type strain of L. formosensis subsp. formosensis is 516T (=NBRC 109475T=BCRC 80576T).


Assuntos
Lactococcus/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Genes Bacterianos , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
J Med Microbiol ; 70(8)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34463608

RESUMO

Introduction. There are several ß-lactamase genes described for Bacteroides strains, of which cepA and cfiA are specific for Bacteroides fragilis and define two genetic divisions. The expression and phenotypic effects of these genes are usually regulated by insertional activation.Hypotheses/Gap Statement. Information is lacking about how cepA is regulated for most of the B. fragilis strains and whether there could be a genetic element for it.Aim. We aimed to investigate the molecular background of ampicillin (and other ß-lactam) resistance among Bacteroides strains as mediated mainly by cepA and also to find a genetic element for it as known for cfiA.Methodology. Various PCR methods were used for ß-lactamase-resistance gene and insertion sequence (IS) element detection in 42 Bacteroides strains. ß-Lactamase activity measurements and antimicrobial-susceptibility testing using agar dilution were also applied. Further molecular experiments involved sequencing, gene targeting, Southern blotting and bioinformatic analyses.Results. We found that high antibiotic resistance and ß-lactamase levels are brought about by insertional activation of the cepA gene or by similar or dissimilar activation of cfxA or cfiA, or by the newly described pbbA genes. Non-activated cepA genes produced low levels of specific ß-lactamase activities that did not correlate with ampicillin resistance. We found a genetic element for cepA and another region close to it that are characteristic for division I B. fragilis strains, which are replaced by other sequences in division II B. fragilis strains.Conclusion. cepA usually is not activated by IS elements and usually produces low ß-lactamase activities that do not correlate with the ampicillin MICs; therefore, it probably involves some non-ß-lactamase-mediated resistance mechanism(s). pbpA is a newly described, effective ß-lactamase gene that is located on a plasmid, and cepA resides on a well-defined chromosomal segment that is mutually replaced in division II B. fragilis strains. This latter finding demonstrates the genetic dichotomy of cepA-cfiA in B. fragilis and requires further investigation.


Assuntos
Resistência a Ampicilina/genética , Infecções por Bacteroides/microbiologia , Bacteroides fragilis/genética , beta-Lactamases/genética , Proteínas de Bactérias/genética , Genes Bacterianos
12.
J Med Microbiol ; 70(8)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34397349

RESUMO

Introduction. Lactococcus petauri LZys1 (L. petauri LZys1) is a type of lactic acid bacteria (LAB), which was initially isolated from healthy human gut.Hypothesis/Gap Statement. It was previously anticipated that L. petauri LZys1 has potential characteristics of probiotic properties. The genetic structure and the regulation functions of L. petauri LZys1 need to be better revealed.Aim. The aim of this study was to detect the probiotic properties L. petauri LZys1 and to reveal the genome information related to its genetic adaptation and probiotic profiles.Methodology. Multiple in vitro experiments were carried out to evaluate its lactic acid-producing ability, resistance to pathogenic bacterial strains, auto-aggregation and co-aggregation ability, and so on. Additionally, complete genome sequencing, gene annotation, and probiotic associated gene analysis were performed.Results. The complete genome of L. petauri LZys1 comprised of 1 985 765 bp, with a DNA G+C content of 38.07 %, containing 50 tRNA, seven rRNA, and four sRNA. A total of 1931 genes were classified into six functional categories by Kyoto Encyclopaedia of Genes and Genomes (KEGG) database. The neighbour-joining phylogeny tree based on the whole genome of L. petauri LZys1 and other probiotics demonstrated that L. petauri LZys1 has a significant similarity to Lactococcus garvieae. The functional genes were detected to expound the molecular mechanism and biochemical processes of its potential probiotic properties, such as atpB gene.Conclusion. All the results described in this study, together with relevant information previously reported, made L. prtauri LZys1 a very interesting potential strain to be considered as a prominent candidate for probiotic use.


Assuntos
Trato Gastrointestinal/microbiologia , Genoma Bacteriano , Lactococcus , Probióticos , Animais , Bactérias/crescimento & desenvolvimento , Bactérias/patogenicidade , Sequência de Bases , Fezes/microbiologia , Genes Bacterianos , Humanos , Lactococcus/citologia , Lactococcus/genética , Lactococcus/isolamento & purificação , Lactococcus/fisiologia , Masculino , Anotação de Sequência Molecular , Mariposas/microbiologia , Filogenia , Polissacarídeos Bacterianos/biossíntese , Polissacarídeos Bacterianos/genética , Sequenciamento Completo do Genoma , Adulto Jovem
13.
Nat Commun ; 12(1): 4702, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34349104

RESUMO

Mycobacterium tuberculosis can adapt to changing environments by non-heritable mechanisms. Frame-shifting insertions and deletions (indels) may also participate in adaptation through gene disruption, which could be reversed by secondary introduction of a frame-restoring indel. We present ScarTrek, a program that scans genomic data for indels, including those that together disrupt and restore a gene's reading frame, producing "frame-shift scars" suggestive of reversible gene inactivation. We use ScarTrek to analyze 5977 clinical M. tuberculosis isolates. We show that indel frequency inversely correlates with genomic linguistic complexity and varies with gene-position and gene-essentiality. Using ScarTrek, we detect 74 unique frame-shift scars in 48 genes, with a 3.74% population-level incidence of unique scar events. We find multiple scars in the ESX-1 gene cluster. Six scars show evidence of convergent evolution while the rest shared a common ancestor. Our results suggest that sequential indels are a mechanism for reversible gene silencing and adaptation in M. tuberculosis.


Assuntos
Adaptação Fisiológica/genética , Inativação Gênica , Mycobacterium tuberculosis/genética , Fases de Leitura/genética , Evolução Molecular , Genes Bacterianos/genética , Genoma Bacteriano/genética , Humanos , Mutação INDEL , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/microbiologia
14.
J Environ Sci (China) ; 107: 150-159, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34412778

RESUMO

The black soldier fly larvae (BSFL) have been successfully applied to treat various organic wastes. However, the impacts of heavy metals on antibiotic resistance in the BSFL guts are poorly understood. Here, we investigated the effect of copper (exposure concentrations of 0, 100 and 800 mg/kg) on the antibiotic and metal resistance profiles in BSFL guts. A total of 83 antibiotic resistance genes (ARGs), 18 mobile genetic elements (MGEs) and 6 metal resistance genes (MRGs) were observed in larval gut samples. Exposure to Cu remarkably reduced the diversity of ARGs and MGEs, but significantly enhanced the abundances of gut-associated ARGs and MRGs. The levels of MRGs copA, czcA and pbrT were dramatically strengthened after Cu exposure as compared with CK (increased by 2.8-13.5 times). Genera Enterococcus acted as the most predominant potential host of multiple ARG, MGE and MRG subtypes. Meanwhile, high exposure to Cu aggravated the enrichment of potential pathogens in BSFL guts, especially for Escherichia, Enterococcus and Salmonella species. The mantel test and procrustes analysis revealed that the gut microbial communities could be a key determinant for antibiotic and metal resistance. However, no significant positive links were observed between MGEs and ARGs or MRGs, possibly suggesting that MGEs did not play a crucial role in shaping the ARGs or MRGs in BSFL guts under the stress of Cu. These findings extend our understanding on the impact of heavy metals on the gut-associated antibiotic and metal resistome of BSFL.


Assuntos
Dípteros , Metais Pesados , Animais , Cobre/toxicidade , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Incidência , Larva , Metais Pesados/toxicidade
15.
Huan Jing Ke Xue ; 42(9): 4358-4365, 2021 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-34414734

RESUMO

Wastewater from antibiotic production usually contains a huge amount of antibiotic resistance genes (ARG). Therefore, it is essential to study the dissemination and control of antibiotic resistance during the treatment of antibiotic production wastewater. The mutual influence between microbial community evolution, wastewater characteristics, and ARG was investigated using high-throughput sequencing and a variety of statistical analysis methods. Results showed that the influent characteristics had only a marginal influence on the microbial community of each treatment section. Methanogenic bacteria and sulfate-reducing bacteria were the dominant microbes in the anaerobic and anoxic tank. Chemical oxygen demand (COD), NO2--N, and PO43--P exhibited an intimate relationship with the microbial community, whereas biomass, NH4+-N, and COD showed a strong correlation with ARG and mobile genetic elements (MGE). In the sludge, more genera (including pathogenic bacteria) were significantly correlated with ARG and MGE than that in the wastewater, indicating that bacteria in the sludge had a greater chance of acquiring pathogenicity and resistance. Therefore, more attnetion should be given to waste sludge from the treatment plants of antibiotic production wastewater. This research could provide further understanding of antibiotic resistance dissemination and control during wastewater treatment, especially for antibiotic production wastewater.


Assuntos
Microbiota , Espiramicina , Purificação da Água , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos/genética , Águas Residuárias
16.
Nat Commun ; 12(1): 4765, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362925

RESUMO

Antibiotic resistance genes (ARGs) are widespread among bacteria. However, not all ARGs pose serious threats to public health, highlighting the importance of identifying those that are high-risk. Here, we developed an 'omics-based' framework to evaluate ARG risk considering human-associated-enrichment, gene mobility, and host pathogenicity. Our framework classifies human-associated, mobile ARGs (3.6% of all ARGs) as the highest risk, which we further differentiate as 'current threats' (Rank I; 3%) - already present among pathogens - and 'future threats' (Rank II; 0.6%) - novel resistance emerging from non-pathogens. Our framework identified 73 'current threat' ARG families. Of these, 35 were among the 37 high-risk ARGs proposed by the World Health Organization and other literature; the remaining 38 were significantly enriched in hospital plasmids. By evaluating all pathogen genomes released since framework construction, we confirmed that ARGs that recently transferred into pathogens were significantly enriched in Rank II ('future threats'). Lastly, we applied the framework to gut microbiome genomes from fecal microbiota transplantation donors. We found that although ARGs were widespread (73% of genomes), only 8.9% of genomes contained high-risk ARGs. Our framework provides an easy-to-implement approach to identify current and future antimicrobial resistance threats, with potential clinical applications including reducing risk of microbiome-based interventions.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Bactérias/efeitos dos fármacos , Bactérias/genética , Bases de Dados Factuais , Microbioma Gastrointestinal/efeitos dos fármacos , Genes Bacterianos/efeitos dos fármacos , Genoma , Humanos , Metagenoma , Plasmídeos
17.
J Med Microbiol ; 70(8)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34338626

RESUMO

Introduction. Biofilm formation is a major virulence factor associated with Staphylococcus aureus infections. However, the influence of plasma proteins on biofilm formation of clinical isolates in vitro remains unclear.Hypotheses. We hypothesized that coating surfaces with plasma proteins might induce biofilm formation by S. aureus of different clonal lineages.Aim. To evaluate biofilm production by clinical S. aureus isolates of different clonal lineages isolated in Rio de Janeiro hospitals and investigated the presence of biofilm-associated genes.Methodology. This study assessed biofilm production of 60 S. aureus isolates in polystyrene microtitre plates with and without fibrinogen or fibronectin. The biochemical composition of the biofilm matrices was determined and the biofilm formation on fibrinogen-coated surfaces was also evaluated by confocal laser scanning microscopy. The presence of biofilm-related genes was detected by PCR, and the typing and functionality of agr operon was also evaluated.Results. Most of the isolates (45 %) were weak biofilm producers or non-producers. However, most of them presented a significant increase in biofilm production on plates covered with plasma proteins. There was no significant difference in biofilm formation between methicillin-resistant and -susceptible S. aureus isolates, or between different clonal lineages, except for ST30-IV (weak producers) and ST239-III (strong producers). The fnbB gene was associated with higher biofilm production.Conclusion. An increase in biofilm production in the presence of plasma proteins highlights the importance of investigating biofilm formation by S. aureus clinical isolates under different conditions since this virulence factor contributes to persistent infections and increased resistance to antimicrobials.


Assuntos
Biofilmes/crescimento & desenvolvimento , Fibrinogênio , Fibronectinas , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Staphylococcus aureus/patogenicidade , Adesinas Bacterianas/genética , Aderência Bacteriana/genética , Proteínas de Bactérias/genética , Genes Bacterianos , Genótipo , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/fisiologia , Óperon , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/fisiologia , Transativadores/genética
18.
Environ Pollut ; 286: 117560, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34438490

RESUMO

As a common natural phenomenon, corpse decomposition may lead to serious environmental pollution such as nitrogen pollution. However, less is known about antibiotic resistance genes (ARGs), an emerging contaminant, during corpse degradation. Here, ARGs and microbiome in three soil types (black, red and yellow soil) have been investigated between experimental and control groups based on next-generation sequencing and high-throughput quantitative PCR techniques. We found that the absolute abundance of total ARGs and mobile genetic elements (MGEs) in the experimental groups were respectively enriched 536.96 and 240.60 times in different soil types, and the number of ARGs in experimental groups was 7-25 more than that in control groups. For experimental groups, the distribution of ARGs was distinct in different soil types, but sulfonamide resistance genes were always enriched. Corpse decomposition was a primary determinant for ARGs profiles. Microbiome, NH4+ concentrates and pH also significantly affected ARGs profiles. Nevertheless, soil types had few effects on ARGs. For soil microbiome, some genera were elevated in experimental groups such as the Ignatzschineria and Myroides. The alpha diversity is decreased in experimental groups and microbial community structures are different between treatments. Additionally, the Escherichia and Neisseria were potential pathogens elevated in experimental groups. Network analysis indicated that most of ARGs like sulfonamide and multidrug resistance genes presented strong positively correlations with NH4+ concentrates and pH, and some genera like Ignatzschineria and Dysgonomonas were positively correlated with several ARGs such as aminoglycoside and sulfonamide resistance genes. Our study reveals a law of ARGs' enrichment markedly during corpse decomposing in different soil types, and these ARGs contaminant maintaining in environment may pose a potential threat to environmental safety and human health.


Assuntos
Antibacterianos , Solo , Animais , Antibacterianos/farmacologia , Cadáver , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Humanos , Microbiologia do Solo
19.
Sci Total Environ ; 790: 148262, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34380279

RESUMO

Although antimicrobial resistance genes (ARGs) in dozens of environments have been well documented, the distribution of ARGs in salt lake ecosystems has been less intensively investigated. In this study, the broad-spectrum ARG profiles, microbial community composition and the comprehensive associations between microbiome and antimicrobial resistome in four salt lakes were investigated using a metagenomic approach. A total of 175 ARG subtypes affiliated with 19 ARG types were detected, and ARGs conferring resistance to multidrug, bacitracin, and macrolide-lincosamide-streptogramin (MLS) accounted for 71.2% of the total ARG abundance. However, the abundance of ARGs significantly decreased with the increasing salinity in the lakes. Both ARG profiles and microbial community structure presented remarkable discrepancies in different lakes, as well as in different sample types. Microbes such as genera Azoarcus, Aeromonas, Pseudomonas, and Kocuria, significantly co-occurred with multiple ARGs, indicating that these bacteria are potential ARG hosts in salt lake ecosystems. Collectively, this work provides new insights into the occurrence and distribution of ARGs in salt lake ecosystems.


Assuntos
Metagenômica , Microbiota , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Lagos
20.
Int J Mol Sci ; 22(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34360905

RESUMO

Some Listeria species are important human and animal pathogens that can be found in contaminated food and produce a variety of virulence factors involved in their pathogenicity. Listeria strains exhibiting multidrug resistance are known to be progressively increasing and that is why continuous monitoring is needed. Effective therapy against pathogenic Listeria requires identification of the bacterial strain involved, as well as determining its virulence factors, such as antibiotic resistance and sensitivity. The present study describes the use of liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) to do a global shotgun proteomics characterization for pathogenic Listeria species. This method allowed the identification of a total of 2990 non-redundant peptides, representing 2727 proteins. Furthermore, 395 of the peptides correspond to proteins that play a direct role in Listeria pathogenicity; they were identified as virulence factors, toxins and anti-toxins, or associated with either antibiotics (involved in antibiotic-related compounds production or resistance) or resistance to toxic substances. The proteomic repository obtained here can be the base for further research into pathogenic Listeria species and facilitate the development of novel therapeutics for these pathogens.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/química , Farmacorresistência Bacteriana Múltipla , Listeria/efeitos dos fármacos , Listeria/patogenicidade , Proteoma/química , Fatores de Virulência/química , Transportadores de Cassetes de Ligação de ATP/química , Cromatografia Líquida/métodos , Genes Bacterianos , Listeria/classificação , Listeria/genética , Peptídeos/química , Proteômica/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
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