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1.
Rev Peru Med Exp Salud Publica ; 38(2): 308-312, 2021.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-34468581

RESUMO

This study aimed to determine the frequency of colistin resistance in Pseudomonas aeruginosa isolates obtained from three healthcare facilities in Lima and cryopreserved at the Laboratorio de Resistencia Antimicrobianos e Inmunopatología of the Universidad Peruana Cayetano Heredia (UPCH). The colistin broth disk elution method was used for the phenotypic identification of colistin resistance. We detected the expression of the mcr-1 gene by using the phenotypic diffusion method with combined colistin and ethylenediaminetetraacetic acid (EDTA) disks; and polymerase chain reaction (PCR) was used for molecular identification of the gene. Of the 97 isolates, 7 (7.2%) were resistant to colistin; however, none carried the mcr-1 gene. This is the first report from Peru on clinical isolates of colistin-resistant Pseudomonas aeruginosa, which suggests the need for implementation of appropriate methodologies for the epidemiological surveillance of colistin-resistant pathogens.


Assuntos
Colistina , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Colistina/farmacologia , Farmacorresistência Bacteriana/genética , Testes de Sensibilidade Microbiana , Peru , Pseudomonas aeruginosa/genética
2.
Ethiop J Health Sci ; 31(3): 663-672, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34483624

RESUMO

Background: This cross-sectional study was performed on isolates of Klebsiella pneumoniae, and E.coli from clinical specimens of patients admitted to Sayyad Shirazi Hospital by census sampling method in 2019. Antibiogram testing was performed using the disk diffusion method as defined by the Clinical and Laboratory Standards Organization for performing this test. Finally, the abundance of genes was evaluated by PCR using specific primers. Frequency, percentage, mean±SD were used to describe the data. Chi-square and Fisher's exact tests were used to compare the presence and absence of the studied genes alone and in the presence of each other. Result: This study was performed on 130 positive samples, isolated from 32 (24.6%) males and 98 (65.4%) females with a mean age of 43.78 ± 21.72. From the total number of 130 isolates, 84 (64.6%) consisted of E.coli, and 46 (35.4%) were Klebsiella. Most of the cultures were urine and vaginal (61.5%). The highest antibiotic resistance in isolates was cephalexin and cefazolin (67.9% in E.coli & 63% in Klebsiella). Colistin was identified as the most effective antibiotic (100%) in both. AMPC extendedspectrum ß-lactamase genes were present in 40 (30.8%) isolates. The highest frequency about the gene pattern of AMPC positive ß-lactamase bacteria was correlated to DHA, FOX, and CIT genes, while none of the samples contained the MOX ß-lactamase gene. E.coli and Klebsiella beta-lactamase-producing AMPC isolates were also significantly correlated with antibiotic resistance to the cephalosporin class (P <0.05). Conclusion: This study indicated a high percentage of resistance to third and fourth generation cephalosporins. Hence, careful antibiogram tests and prevention of antibiotic overuse in infections caused by AMPC-producing organisms and screening of clinical samples for the resistance mentioned above genes and providing effective strategies to help diagnose and apply appropriate treatments and change antibiotic usage strategies can partially prevent the transmission of this resistance.


Assuntos
Farmacorresistência Bacteriana/genética , Escherichia coli , Klebsiella pneumoniae , Antibacterianos/farmacologia , Estudos Transversais , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Infecções por Escherichia coli/tratamento farmacológico , Feminino , Humanos , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Masculino , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
3.
J Med Microbiol ; 70(9)2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34477546

RESUMO

Introduction. Carbapenem-resistant enterobacterales (CRE) are listed among the most urgent antibiotic resistance threats.Hypothesis. Previous studies on the mechanisms of CRE in Kuwait have focused on carbapenemases. There have been no studies on non-carbapenemase-producing CRE in Kuwait.Aim/Gap Statement. The aim of this study was to investigate the genetic characteristics of non-carbapenemase-producing carbapenem-resistant enterobacterales (NCPE) isolates using whole-genome sequencing (WGS).Methodology. Fourteen confirmed NCPE isolates that were negative for genes encoding carbapenemase production by polymerase chain reaction (PCR) assays using rectal swabs from intensive care unit patients were characterized using phenotypic, PCR and WGS methods. Susceptibility testing was performed via Etest and clonality via multi-locus sequence typing (MLST).Results. All of the isolates were resistant to ertapenem; 78.6 % were resistant to imipenem, meropenem and trimethoprim-sulfamethoxazole. Resistance to the other antibiotics was variable, ranging from 28.5 (colistin) through 50 (tigecycline) and 64.3 (amikacin) up to 85.7 % against both amoxicillin-clavulanic acid and ciprofloxacin. WGS detected several resistance genes mediating the production of ß-lactamases, genes encoding an outer-membrane porin permeability mutation resulting in reduced susceptibility to ß-lactams, including carbapenems, and genes for multidrug-resistant (MDR) efflux pumps. The isolates also possessed global activator protein MarA, which mediated reduced permeability to ß-lactams. The existence of ß-lactamase genes, overexpression of MDR efflux pumps and reduced permeability mediated by the porin genes were responsible for carbapenem resistance.Conclusions. This finding reflects the superior detection capabilities offered by WGS analysis, which can be used to complement traditional methods and overcome their limited resolution in clinical settings.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Farmacorresistência Bacteriana/genética , Infecções por Enterobacteriaceae/microbiologia , Trato Gastrointestinal/microbiologia , Sequenciamento Completo do Genoma/métodos , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Humanos , Kuweit/epidemiologia
4.
Microbiome ; 9(1): 178, 2021 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-34454634

RESUMO

BACKGROUND: Therapeutic and growth-promoting antibiotics are frequently used in broiler production. Indirect evidence indicates that these practices are linked to the proliferation of antimicrobial resistance (AMR), the spread of antibiotic-resistant bacteria from food animals to humans, and the environment, but there is a lack of comprehensive experimental data supporting this. We investigated the effects of growth promotor (bacitracin) and therapeutic (enrofloxacin) antibiotic administration on AMR in broilers for the duration of a production cycle, using a holistic approach that integrated both culture-dependent and culture-independent methods. We specifically focused on pathogen-harboring families (Enterobacteriaceae, Enterococcaceae, and Staphylococcaceae). RESULTS: Antibiotic-resistant bacteria and antibiotic resistance genes were ubiquitous in chicken cloaca and litter regardless of antibiotic administration. Environment (cloaca vs. litter) and growth stage were the primary drivers of variation in the microbiomes and resistomes, with increased bacterial diversity and a general decrease in abundance of the pathogen-harboring families with age. Bacitracin-fed groups had higher levels of bacitracin resistance genes and of vancomycin-resistant Enterococcaceae (total Enterococcaceae counts were not higher). Although metagenomic analyses classified 28-76% of the Enterococcaceae as the commensal human pathogens E. faecalis and E. faecium, culture-based analysis suggested that approximately 98% of the vancomycin-resistant Enterococcaceae were avian and not human-associated, suggesting differences in the taxonomic profiles of the resistant and non-resistant strains. Enrofloxacin treatments had varying effects, but generally facilitated increased relative abundance of multidrug-resistant Enterobacteriaceae strains, which were primarily E. coli. Metagenomic approaches revealed a diverse array of Staphylococcus spp., but the opportunistic pathogen S. aureus and methicillin resistance genes were not detected in culture-based or metagenomic analyses. Camphylobacteriaceae were significantly more abundant in the cloacal samples, especially in enrofloxacin-treated chickens, where a metagenome-assembled C. jejuni genome harboring fluoroquinolone and ß-lactam resistance genes was identified. CONCLUSIONS: Within a "farm-to-fork, one health" perspective, considering the evidence that bacitracin and enrofloxacin used in poultry production can select for resistance, we recommend their use be regulated. Furthermore, we suggest routine surveillance of ESBL E. coli, vancomycin-resistant E. faecalis and E. faecium, and fluoroquinolone-resistant C. jejuni strains considering their pathogenic nature and capacity to disseminate AMR to the environment. Video Abstract.


Assuntos
Galinhas , Microbiota , Animais , Antibacterianos/farmacologia , Cloaca , Farmacorresistência Bacteriana/genética , Escherichia coli , Humanos , Estudos Longitudinais , Staphylococcus aureus
5.
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
6.
Pan Afr Med J ; 39: 22, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34394813

RESUMO

Introduction: the spread of enterobacteria producing extended-broad-spectrum beta-lactamases (ESBL) is a global public health-problem. In a study carried in 2003-2005 at the Pasteur Institute in Bangui, 450 enterobacteria were identified in clinical isolates, of which 17 were ESBL (prevalence: 3.78%). The aim of this study was to update this data. Methods: from May 2018 to April 2019, a total of 941 enterobacteria were isolated and identified under identical conditions of recruitment and with the same techniques used in the previous study: phenotypic identification using Api 20E strips (bioMérieux SA, Marcy-l'Etoile, France) and antimicrobial drug susceptibility using the disk diffusion method (Bio-Rad antibiotic discs, Marnes la Coquette, France). Resistance genes were identified by polymerase chain reaction (PCR) and sequencing. Results: from May 2018 to April 2019, a total of 941 enterobacteria were isolated of which 478 were ESBL, thus amounting to a prevalence of 50.80%. The genetic profiles of the bla CTX-M resistance genes exhibited the emergence of the CTX-M28 variant (CTX-M1 group) and variants of the M2 and M9 groups. There was also a notable increase, from 35 to 64%, in the ESBL with a bla SHV gene. Conclusion: this study documents a 13 fold increase in the prevalence of ESBL derived from clinical isolates of the bacteriology laboratory of the Institute Pasteur in Bangui, by comparing its data with that of the publication by Frank et al. 2006. Together with this increase a significant diversification of the circulating CTX-M resistance genes was noticed.


Assuntos
Antibacterianos/farmacologia , Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/isolamento & purificação , beta-Lactamases/genética , Proteínas de Bactérias/genética , República Centro-Africana/epidemiologia , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Infecções por Enterobacteriaceae/microbiologia , Humanos , Reação em Cadeia da Polimerase , Estudos Retrospectivos
7.
Clin Lab ; 67(8)2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34383410

RESUMO

BACKGROUND: To investigate the epidemics of plasmid-mediated quinolone resistance (PMQR) gene in carbapenem-resistant Enterobacteriaceae (CRE) and the resistance mechanism. METHODS: We collected CRE bacteria isolated clinically between December 2017 and December 2018 for identification and drug sensitivity testing using a VITEK2 Compact Analyzer. Furthermore, genes, including qnrA, qnrB, qnrS, qepA, and acc (6') Ib-cr, were determined through the polymerase chain reaction and sequencing. The hori-zontal transfer of PMQR gene was validated through the plasmid conjugational test. RESULTS: Drug resistance rate of carbapenem-resistant Escherichia coli against quinolones was 100%, while the rate of carbapenem-resistant Klebsiella pneumoniae ranged from 15.56% to 33.33%. The detection rate of acc (6') Ib-cr was the highest (87.72%), followed by qnrB (77.19%) and qnrS (17.54%). Additionally, there were two bacteria carrying the qnrA gene (3.51%), but qepA gene was not isolated from the samples. In total, 84.21% of these bacteria carried 2 or 3 kinds of PMQR genes. Among 8 bacteria with successful plasmid conjugation, PMQR gene transfer was detected in all of them, but with no significant change in the minimum inhibitory concentration of quinolones. CONCLUSIONS: CRE remain sensitive to quinolones in spite of the high detection rate of PMQR gene in this hospital.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Enterobacteriaceae , Quinolonas , Antibacterianos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Farmacorresistência Bacteriana/genética , Infecções por Enterobacteriaceae/diagnóstico , Infecções por Enterobacteriaceae/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Quinolonas/farmacologia
8.
Adv Protein Chem Struct Biol ; 127: 343-364, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34340773

RESUMO

BACKGROUND AND AIM: The persistence of extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis (MTB) continue to pose a significant challenge to the treatment and control of tuberculosis infections worldwide. XDR-MTB strains exhibit resistance against first-line anti-TB drugs, fluoroquinolones, and second-line injectable drugs. The mechanisms of drug resistance of MTB remains poorly understood. Our study aims at identifying the differentially expressed genes (DEGs), associated gene networks, and signaling cascades involved in rendering this pathogen resistant to multiple drugs, namely, isoniazid, rifampicin, and capreomycin. METHODS: We used the microarray dataset GSE53843. The GEO2R tool was used to prioritize the most significant DEGs (top 250) of each drug exposure sample between XDR strains and non-resistant strains. The validation of the 250 DEGs was performed using volcano plots. Protein-protein interaction networks of the DEGs were created using STRING and Cytoscape tools, which helped decipher the relationship between these genes. The significant DEGs were functionally annotated using DAVID and ClueGO. The concomitant biological processes (BP) and molecular functions (MF) were represented as dot plots. RESULTS AND CONCLUSION: We identified relevant molecular pathways and biological processes, such as cell wall biogenesis, lipid metabolic process, ion transport, phosphopantetheine binding, and triglyceride lipase activity. These processes indicated the involvement of multiple interconnected mechanisms in drug resistance. Our study highlighted the impact of cell wall permeability, with the dysregulation of the mur family of proteins, as essential factors in the inference of resistance. Additionally, upregulation of genes responsible for ion transport such as ctpF, arsC, and nark3, emphasizes the importance of transport channels and efflux pumps in potentially driving out stress-inducing compounds. This study investigated the upregulation of the Lip family of proteins, which play a crucial role in triglyceride lipase activity. Thereby illuminating the potential role of drug-induced dormancy and subsequent resistance in the mycobacterial strains. Multiple mechanisms such as carboxylic acid metabolic process, NAD biosynthetic process, triglyceride lipase activity, phosphopantetheine binding, organic acid biosynthetic process, and growth of symbiont in host cell were observed to partake in resistance of XDR-MTB. This study ultimately provides a platform for important mapping targets for potential therapeutics against XDR-MTB.


Assuntos
Proteínas de Bactérias , Farmacorresistência Bacteriana/genética , Tuberculose Extensivamente Resistente a Medicamentos , Regulação Bacteriana da Expressão Gênica , Mycobacterium tuberculosis , Biologia de Sistemas , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Tuberculose Extensivamente Resistente a Medicamentos/genética , Tuberculose Extensivamente Resistente a Medicamentos/metabolismo , Humanos
9.
J Med Microbiol ; 70(8)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34356003

RESUMO

Introduction. Fluoroquinolone (FQ) resistant Salmonella are classified as high priority pathogens by WHO. FQ resistance among Salmonella Typhi has emerged rapidly and is predominantly mediated by mutations in the topoisomerase genes gyrA, and parC. Mutations in GyrA result in classical FQ resistance (DCS-NAR) i.e. decreased susceptibility to ciprofloxacin (MIC of 0.12 to 0.5 µg ml-1) (DCS) and resistance to nalidixic acid (NAR). Previously a nalidixic acid disc test was proposed for detection of DCS. Recently isolates with non-classical FQ resistance caused by plasmid-mediated quinolone resistance (PMQR) and mutations in GyrB have emerged. These mechanisms also result in DCS but are nalidixic acid susceptible (NAS) and thus pose diagnostic challenges. CLSI and EUCAST have recommended use of 5 µg pefloxacin discs for detection of DCS in Salmonella.Hypothesis. The CLSI and EUCAST recommendations for use of 5 µg pefloxacin for detection of DCS has not been validated on typhoidal Salmonella and resistance mediated by GyrB mutation in Salmonella species.Aim. The aim of the present study was to validate the performance of the 5 µg pefloxacin discs to detect isolates of S. Typhi with DCS with special reference to GyrB mutations.Methodology. A total of 180 clinical isolates of Salmonella Typhi (2005-2014) were investigated for genetic mechanisms of resistance. Zone diameters for nalidixic acid (30µg), ciprofloxacin (5µg) and pefloxacin (5µg) and minimum inhibitory concentration (MIC) for ciprofloxacin were determined using CLSI guidelines. Performance of the three discs was evaluated to detect FQ resistance in S. Typhi.Results. Topoisomerase mutations in GyrB +/ ParC and GyrB were detected in 112 and 34 isolates respectively. Different mutations have a varied effect on the MIC for ciprofloxacin. The current breakpoints for susceptible (≤0.06 µg ml-1) and non-susceptible (≥0.125 µg ml-1), failed to detect all isolates with a resistance mechanism. Performance of both ciprofloxacin and pefloxacin discs were excellent compared to nalidixic acid in differentiating isolates with non-classical resistance mediated by GyrB from wild-type.Conclusion. The pefloxacin disc can be used to detect FQ resistance among S. Typhi. This is the first report of validation of pefloxacin for detection of FQ resistance in S. Typhi mediated by GyrB mutation.


Assuntos
DNA Girase/genética , Farmacorresistência Bacteriana/efeitos dos fármacos , Fluoroquinolonas/farmacologia , Pefloxacina/farmacologia , Salmonella typhi/efeitos dos fármacos , Antibacterianos/farmacologia , Ciprofloxacina/farmacologia , DNA Topoisomerase IV/genética , Farmacorresistência Bacteriana/genética , Humanos , Testes de Sensibilidade Microbiana , Mutação , Ácido Nalidíxico/farmacologia , Salmonella typhi/genética , Salmonella typhi/isolamento & purificação , Inibidores da Topoisomerase II/farmacologia , Febre Tifoide/microbiologia
10.
BMC Genomics ; 22(1): 627, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34425756

RESUMO

BACKGROUND: Streptococcus agalactiae (Group B Streptococcus, GBS) is one of the major bacterial pathogens responsible for neonatal sepsis. Whole genome sequencing has, in recent years, emerged as a reliable tool for capsular typing and antimicrobial resistance prediction. This study characterized vaginal and rectal isolates of Group B Streptococcus obtained from pregnant women in Port Harcourt, Nigeria using a whole-genome sequence-based approach. RESULTS: Capsular types Ia, Ib, II, III, IV and V were detected among the 43 isolates sequenced. Twelve sequence types (STs) were identified, with ST19 (n = 9, 27.3 %) and ST486 (n = 5, 15.2 %) the most frequent among non-duplicated isolates. Of the alpha-like proteins (alp) identified, Alp1 was the most prevalent in 11 (33.3 %) isolates. Macrolide and lincosamide resistance determinants were present in 15 (45.5 %) isolates; ermB was detected in 1 (3 %), ermTR in 7 (21.2 %) isolates, lnu gene was detected in 6 (18.2 %) and mef was identified in 3 (9.1 %) isolates. Resistance of GBS to erythromycin and clindamycin (predicted from presence of erm or mef genes) was found to be 30.3 % and 24.2 %, respectively. All isolates were predicted resistant to tetracycline with only the tetM gene identified. Fluoroquinolone-resistance conferring substitutions in gyrA + parC were detected in 9 (27.3 %) isolates and chloramphenicol resistance was predicted from presence of aac6'-aph2 gene in 11 (33.3 %). CONCLUSIONS: The data available from the whole genome sequencing of these isolates offers a small but insightful description of common serotypes and resistance features within colonizing GBS in Nigeria.


Assuntos
Antibacterianos , Streptococcus agalactiae , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Feminino , Humanos , Recém-Nascido , Nigéria , Gravidez , Gestantes , Streptococcus agalactiae/genética
11.
Int J Mol Sci ; 22(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199768

RESUMO

Single mutations can confer resistance to antibiotics. Identifying such mutations can help to develop and improve drugs. Here, we systematically screen for candidate quinolone resistance-conferring mutations. We sequenced highly diverse wastewater E. coli and performed a genome-wide association study (GWAS) to determine associations between over 200,000 mutations and quinolone resistance phenotypes. We uncovered 13 statistically significant mutations including 1 located at the active site of the biofilm dispersal gene bdcA and 6 silent mutations in the aminoacyl-tRNA synthetase valS. The study also recovered the known mutations in the topoisomerases gyrase (gyrA) and topoisomerase IV (parC). In summary, we demonstrate that GWAS effectively and comprehensively identifies resistance mutations without a priori knowledge of targets and mode of action. The results suggest that mutations in the bdcA and valS genes, which are involved in biofilm dispersal and translation, may lead to novel resistance mechanisms.


Assuntos
Farmacorresistência Bacteriana/genética , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Mutação/genética , Quinolonas/farmacologia , Valina-tRNA Ligase/genética , Águas Residuárias/microbiologia , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Loci Gênicos , Estudo de Associação Genômica Ampla , Desequilíbrio de Ligação/genética , Modelos Moleculares , Fenótipo , Filogenia
12.
Sci Total Environ ; 795: 148815, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34247085

RESUMO

Extensive use of antibiotics is significantly associated with development of antibiotic-resistant (AR) bacteria. However, their causal relationships have not been adequately investigated, especially in human population and hospitals. Our aims were to understand clinical AR through revealing co-occurrence patterns between antibiotic-resistant bacteria and genes (ARB and ARGs), and their association with antibiotic use, and to consider impact of ARB and ARGs on environmental and human health. Antibiotic usage was calculated based on the actual consumption in our target hospital. ARB was identified by culture. In isolates collected from hospital sewage, bacterial-specific DNA sequences and ARGs were determined using metagenomics. Our data revealed that the use of culture-based single-indicator-strain approaches only captured ARB in 16.17% of the infectious samples. On the other hand, 1573 bacterial species and 885 types of ARGs were detected in the sewage. Furthermore, hospital use of antibiotics influenced the resistance profiles, but the strength varied among bacteria. From our metagenomics analyses, ARGs for aminoglycosides were the most common, followed by sulfonamide, tetracycline, phenicol, macrolides, and quinolones, comprising 82.6% of all ARGs. Association analyses indicated that 519 pairs of ARGs were significantly correlated with ARB species (r > 0.8). The co-occurrence patterns of bacteria-ARGs mirrored the AR in the clinic. In conclusion, our systematic investigation further emphasized that antibiotic usage in hospital significantly influenced the abundance and types of ARB and ARGs in dose- and time-dependent manners which, in turn, mirrored clinical AR. In addition, our data provide novel information on development of certain ARB with multiple antibiotic resistance. These ARB and ARGs from sewage can also be disseminated into the environment and communities to create health problems. Therefore, it would be helpful to use such data to develop improved predictive risk model of AR, to enhance effective use of antibiotics, and to reduce environmental pollution.


Assuntos
Antibacterianos , Esgotos , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Antibacterianos/farmacologia , Bactérias/genética , Farmacorresistência Bacteriana/genética , Genes Bacterianos , Hospitais , Humanos
13.
Front Public Health ; 9: 684456, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222184

RESUMO

Coagulase-negative staphylococci (CoNS) are common opportunistic pathogens, but also ubiquitous human and animal commensals. Infection-associated CoNS from healthcare environments are typically characterized by pronounced antimicrobial resistance (AMR) including both methicillin- and multidrug-resistant isolates. Less is known about AMR patterns of CoNS colonizing the general population. Here we report on AMR in commensal CoNS recovered from 117 non-hospitalized volunteers in a region of Germany with a high livestock density. Among the 69 individuals colonized with CoNS, 29 had reported contacts to either companion or farm animals. CoNS were selectively cultivated from nasal swabs, followed by species definition by 16S rDNA sequencing and routine antibiotic susceptibility testing. Isolates displaying phenotypic AMR were further tested by PCR for presence of selected AMR genes. A total of 127 CoNS were isolated and Staphylococcus epidermidis (75%) was the most common CoNS species identified. Nine isolates (7%) were methicillin-resistant (MR) and carried the mecA gene, with seven individuals (10%) being colonized with at least one MR-CoNS isolate. While resistance against gentamicin, phenicols and spectinomycin was rare, high resistance rates were found against tetracycline (39%), erythromycin (33%) and fusidic acid (24%). In the majority of isolates, phenotypic resistance could be associated with corresponding AMR gene detection. Multidrug-resistance (MDR) was observed in 23% (29/127) of the isolates, with 33% (23/69) of the individuals being colonized with MDR-CoNS. The combined data suggest that MR- and MDR-CoNS are present in the community, with previous animal contact not significantly influencing the risk of becoming colonized with such isolates.


Assuntos
Farmacorresistência Bacteriana , Infecções Estafilocócicas , Animais , Antibacterianos/farmacologia , Coagulase/genética , Farmacorresistência Bacteriana/genética , Alemanha/epidemiologia , Humanos , Infecções Estafilocócicas/tratamento farmacológico
14.
Biomed Environ Sci ; 34(6): 454-464, 2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34284853

RESUMO

Objective: This study was performed to compare the genetic diversity, virulence, and antimicrobial resistance of Aeromonas strains isolated from patients and healthy individuals. Methods: A total of 38 clinical strains and 19 strains from healthy individuals were isolated from the samples collected in Ma'anshan City, Anhui Province. Their taxonomy was investigated using concatenated gyrB- cpn60 sequences, and their resistance to 12 antibiotics was evaluated. The pathogenicity of these strains was examined through beta-hemolysis, protease activity, and virulence gene assays. Results: The 57 Aeromonas strains were divided into 55 sequence types. Of these types, 21 were novel, suggesting that their genetic diversity was high. These Aeromonas isolates could be divided into 7 species, and the positive rates of beta-hemolysis and protease activity were 49.1% and 73.7%, respectively. The detection rate of clinical patients in terms of beta-hemolysis and protease activity was higher than that of healthy individuals. Among the four most common Aeromonas strains, A. dhakensis had the highest detection rate of virulence genes. The multidrug resistance rate of the clinical isolates was much higher than that of the strains isolated from healthy individuals. Conclusions: The taxonomy, virulence properties, and antibiotic resistance of Aeromonas isolates from patients differ from those of the isolates from healthy individuals.


Assuntos
Aeromonas/genética , Farmacorresistência Bacteriana/genética , Aeromonas/isolamento & purificação , Aeromonas/patogenicidade , Estudos de Casos e Controles , Variação Genética , Humanos , Fatores de Virulência/genética
15.
Science ; 373(6554)2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34326207

RESUMO

Bacteriophage predation selects for diverse antiphage systems that frequently cluster on mobilizable defense islands in bacterial genomes. However, molecular insight into the reciprocal dynamics of phage-bacterial adaptations in nature is lacking, particularly in clinical contexts where there is need to inform phage therapy efforts and to understand how phages drive pathogen evolution. Using time-shift experiments, we uncovered fluctuations in Vibrio cholerae's resistance to phages in clinical samples. We mapped phage resistance determinants to SXT integrative and conjugative elements (ICEs), which notoriously also confer antibiotic resistance. We found that SXT ICEs, which are widespread in γ-proteobacteria, invariably encode phage defense systems localized to a single hotspot of genetic exchange. We identified mechanisms that allow phage to counter SXT-mediated defense in clinical samples, and document the selection of a novel phage-encoded defense inhibitor. Phage infection stimulates high-frequency SXT ICE conjugation, leading to the concurrent dissemination of phage and antibiotic resistances.


Assuntos
Farmacorresistência Bacteriana/genética , Sequências Repetitivas Dispersas , Myoviridae/fisiologia , Vibrio cholerae/efeitos dos fármacos , Vibrio cholerae/virologia , Bacteriólise , Cólera/microbiologia , Conjugação Genética , Epigênese Genética , Fezes/microbiologia , Fezes/virologia , Gammaproteobacteria/genética , Gammaproteobacteria/virologia , Genes Bacterianos , Genes Virais , Genoma Bacteriano , Genoma Viral , Especificidade de Hospedeiro , Humanos , Interações Microbianas , Myoviridae/genética , Myoviridae/isolamento & purificação , Vibrio cholerae/genética , Vibrio cholerae/isolamento & purificação , Proteínas Virais/genética , Proteínas Virais/metabolismo
16.
Int J Mol Sci ; 22(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34205867

RESUMO

The increase in the use of antimicrobials such as colistin for the treatment of infectious diseases has led to the appearance of Aeromonas strains resistant to this drug. However, resistance to colistin not only occurs in the clinical area but has also been determined in Aeromonas isolates from the environment or animals, which has been determined by the detection of mcr genes that confer a resistance mechanism to colistin. The variants mcr-1, mcr-3, and mcr-5 have been detected in the genus Aeromonas in animal, environmental, and human fluids samples. In this article, an overview of the resistance to colistin in Aeromonas is shown, as well as the generalities of this molecule and the recommended methods to determine colistin resistance to be used in some of the genus Aeromonas.


Assuntos
Aeromonas/genética , Antibacterianos/química , Colistina/química , Farmacorresistência Bacteriana/genética , Aeromonas/efeitos dos fármacos , Aeromonas/patogenicidade , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Colistina/uso terapêutico , Humanos , Plasmídeos/efeitos dos fármacos , Plasmídeos/genética
17.
World J Gastroenterol ; 27(24): 3595-3608, 2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34239272

RESUMO

BACKGROUND: The drug resistance rate of clinical Helicobacter pylori (H. pylori) isolates has increased. However, the mechanism of drug resistance remains unclear. In this study, drug-resistant H. pylori strains were isolated from different areas and different populations of Chinese for genomic analysis. AIM: To investigate drug-resistant genes in H. pylori and find the genes for the early diagnosis of clarithromycin resistance. METHODS: Three drug-resistant H. pylori strains were isolated from patients with gastritis in Bama County, China. Minimal inhibitory concentrations of clarithromycin, metronidazole, and levofloxacin were determined and complete genome sequencing was performed with annotation. Hp1181 and hp1184 genes were found in these strains and then detected by reverse transcription polymerase chain reaction. The relationships between hp1181 or hp1184 and clarithromycin resistance were ascertained with gene mutant and drug-resistant strains. The homology of the strains with hp26695 was assessed through complete genome detection and identification. Differences in genome sequences, gene quantity, and gene characteristics were detected amongst the three strains. Prediction and analysis of the function of drug-resistant genes indicated that the RNA expression of hp1181 and hp1184 increased in the three strains, which was the same in the artificially induced clarithromycin-resistant bacteria. After gene knockout, the drug sensitivity of the strains was assessed. RESULTS: The strains showing a high degree of homology with hp26695, hp1181, and hp1184 genes were found in these strains; the expression of the genes hp1184 and hp1181 was associated with clarithromycin resistance. CONCLUSION: Hp1181 and hp1184 mutations may be the earliest and most persistent response to clarithromycin resistance, and they may be the potential target genes for the diagnosis, prevention, and treatment of clarithromycin resistance.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , China/epidemiologia , Claritromicina/farmacologia , Farmacorresistência Bacteriana/genética , Diagnóstico Precoce , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/genética , Humanos , Metronidazol/farmacologia , Testes de Sensibilidade Microbiana , RNA Ribossômico 23S
18.
Sheng Wu Gong Cheng Xue Bao ; 37(7): 2503-2512, 2021 Jul 25.
Artigo em Chinês | MEDLINE | ID: mdl-34327915

RESUMO

The purpose of this study is to provide a simple and reliable genetic typing approach for molecular drug susceptibility test of Mycobacterium tuberculosis, through the developing of fluorescence molecular marker of rifampicin resistance gene rpoB. Eleven fluorescent molecular markers of the rpoB gene were established by using the sequence difference between the amino acid positions 531, 526, 516, 511 and 513 of rpoB gene of rifampicin-resistant strains and the alleles of rifampicin-sensitive strains, combined with the PARMS technique (Penta-primer amplification refractory mutation system). We used 104 clinical isolates of Mycobacterium tuberculosis to validate this marker and it was verified by sequencing as 100% correct. These samples were also tested with proportional drug sensitivity test. The coincidence rate was 94.23%. The molecular markers had high reliability for genotyping of rpoB gene. It can also detect low-concentration drug-resistant samples (511/533 unit point mutations) whose phenotypic susceptibility cannot be detected. The eleven sets of fluorescent molecular markers could cover 92%-96% of rpoB gene mutation types of rifampicin-resistant strains, and provide new idea for rapid detection of rifampin-resistant Mycobacterium tuberculosis.


Assuntos
Mycobacterium tuberculosis , Rifampina , Proteínas de Bactérias/genética , RNA Polimerases Dirigidas por DNA/genética , Farmacorresistência Bacteriana/genética , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/genética , Reprodutibilidade dos Testes , Rifampina/farmacologia , Tecnologia
19.
J Med Microbiol ; 70(7)2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34236301

RESUMO

Introduction. Tigecycline is currently acknowledged to be one of the most effective antibiotics against infections caused by Mycobacteroides abscessus.Gap statement. The genetic determinants of tigecycline resistance in M. abscessus are not well understood.Aim. In this study, we characterized a tigecycline-resistant M. abscessus mutant, designated CL7, to identify the potential resistance mechanism.Methodology. CL7 was characterized using antimicrobial susceptibility testing, whole-genome sequencing, PCR and RT-qPCR. For biological verification, gene overexpression assays were carried out.Results. Whole-genome sequencing and the subsequent gene overexpression assays showed that CL7 harboured a stop-gain mutation in MAB_3543 c, which may be responsible for the tigecycline resistance phenotype. This gene encodes an orthologue of SigH, which is involved in the positive regulation of physiological stress response and is negatively regulated by the RshA anti-sigma factor in Mycobacterium tuberculosis. We hypothesized that the MAB_3543 c mutation may disrupt the interaction between SigH and RshA (MAB_3542 c). RT-qPCR analyses revealed the upregulation of MAB_3543 c and other key stress response genes, which has previously been shown to be a hallmark of SigH-RshA bond disruption and tigecycline resistance.Conclusion. The MAB_3543c mutation may represent a novel determinant of tigecycline resistance in M. abscessus. The findings of this study will hopefully contribute to our knowledge of potential tigecycline resistance mechanisms in M. abscessus, which may lead to better diagnostics and treatment modalities in the future.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Mycobacterium abscessus/efeitos dos fármacos , Mycobacterium abscessus/genética , Fator sigma/genética , Tigeciclina/farmacologia , Genoma Bacteriano , Mutação , Sequenciamento Completo do Genoma
20.
Chemosphere ; 281: 130945, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34289613

RESUMO

The global spread of mobilized colistin resistance (mcr) genes in clinical and natural environments dangerously diminishes the effectiveness of this last-resort antibiotic, becoming an urgent health threat. We used a multidisciplinary approach to detect mcr-1 gene and colistin (CL)-resistant bacteria in seawater from two Croatian public beaches. Illumina-based sequencing of metagenomic 16S rRNA was used to assess the taxonomic, functional, and antibiotic resistance genes (ARGs) profiling of the bacterial community tolerant to CL regarding different culture-based isolation methodologies. Data revealed that the choice of methodology alters the diversity and abundance of taxa accounting for the CL-resistance phenotype. The mcr-1 gene was identified by cloning and sequencing in one sample, representing the first report of mcr-1 gene in Croatia. Culturing of CL-resistant strains revealed their resistance phenotypes and concurrent production of clinically significant ß-lactamases, such as CTX-M-15, CTX-M-3 and SHV-12. We also report the first identification of blaCTX-M-15 gene in Klebsiella huaxiensis and K. michiganensis, as well as the blaTEM-1+CTX-M-3 in Serratia fonticola. ARGs profiles derived from metagenomic data and predicted by PICRUSt2, showed the highest abundance of genes encoding for multidrug efflux pumps, followed by the transporter genes accounting for the tetracycline, macrolide and phenicol resistance. Our study evidenced the multidrug resistance features of CL-tolerant bacterial communities thriving in surface beach waters. We also showed that combined application of the metagenomic approaches and culture-based techniques enabled successful detection of mcr-1 gene, which could be underreported in natural environment.


Assuntos
Colistina , Microbiota , Antibacterianos/farmacologia , Colistina/farmacologia , Croácia , Farmacorresistência Bacteriana/genética , Resistência Microbiana a Medicamentos/genética , Microbiota/genética , RNA Ribossômico 16S/genética , Serratia , beta-Lactamases/genética
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