# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 2940 | 0 | 1.0000 | Microbiome and Antimicrobial Resistance Genes in Microbiota of Cloacal Samples from European Herring Gulls (Larus Argentatus). INTRODUCTION: The aim of the study was to determine microbiota in the cloacal samples of European herring gulls (Larus argentatus) and to compare a variety of genes encoding antimicrobial resistance in cultivable and non-cultivable bacteria. MATERIAL AND METHODS: Cloacal samples from European herring gulls were collected from a Kaunas city dump. Cultivable microbiota were isolated, their microbial susceptibility was tested, and genes encoding antimicrobial resistance were detected. Additionally, a metagenomic study was performed using Next-Generation Sequencing (NGS). RESULTS: In total, 697 different operational taxonomic units at genus level were detected; however, only 63 taxonomic units were detected at the amount of ≥0.1% of the total number of DNA copies. Catellicoccus marimammalium was found to have the highest prevalence. The bacterial amount of other genera was up to 5% with the most highly prevalent being Psychrobacter (4.7%), Helicobacter(4.5%), unclassified Enterococcaceae (3.2%), Pseudomonas (2.9%), and Brachyspira (2.6%). CONCLUSIONS: C. marimammalium are predominant microbiota in the cloacal samples of Larus argentatus. This species of gulls is a reservoir of bacteria carrying a wide-spectrum of genes encoding antimicrobial resistance. The same genes were detected in both cultivable microbiota and in the total DNA of the samples. | 2017 | 29978052 |
| 2943 | 1 | 0.9997 | Pilot study of antimicrobial-resistant Escherichia coli in herring gulls (Larus argentatus) and wastewater in the northeastern United States. Wildlife may be an important reservoir of antibiotic-resistant bacteria and resistance genes. In this pilot study, the prevalence and patterns of antimicrobial resistance in Escherichia coli cultured from wild herring gull (Larus argentatus) feces and human wastewater at Cape Cod, Massachusetts, USA, was compared. Antimicrobial susceptibility was tested using Kirby-Bauer disk diffusion with seven antimicrobial agents. A high proportion of antimicrobial agent-resistant E. coli isolates (59.2%) were detected in wastewater samples compared with a lower prevalence of 17.5% in gull feces. In addition, there was a large proportion of isolates with intermediate susceptibility (93.0%) in gull feces. Although similar resistance patterns and shared resistance genes suggest possible wastewater contamination of the local environment, the relatively low frequency of resistance and high prevalence of intermediate susceptibility detected in E. coli cultured from gull feces depict a complex model of antimicrobial resistance among E. coli strains of wildlife origin. | 2011 | 22946391 |
| 2960 | 2 | 0.9997 | Antibiotic resistance, virulence genes, and phylogenetic groups of bacteria isolated from wild passerine birds in Iran. Wild passerine birds may serve as environmental reservoirs and as vectors for the long-distance dispersal of microorganisms and resistance determinants. However, there is no much knowledge on pathogenic bacteria in wild birds in Iran. The present study aimed to analyze antibiotic resistance in wild passerine birds collected from the northeast region of Iran as the rich breeding bird fauna with a special focus on Escherichia coli virulence, integron, and phylogenetic groups. A total of 326 isolates were collected and identified from the cloaca of wild birds using a swab. The results showed a high percentage of resistance to tetracycline (45.8%) and ampicillin (26.7%). The resistance genes, tet(A), tet(B), tet(M), and tet(L) were detected in tetracycline-resistant isolates, while the blaTEM gene was the most prevalent in ampicillin-resistant isolates (38.6%). Out of the 129 E. coli isolates examined, 99 isolates were found to have virulence gene, with the highest prevalence of the fimbriae (fimH) gene (22.4%). Additionally, the E. coli strains were most often classified into phylogenetic groups B1 (48.8%) followed by B2 (19.3%). Also, the highest average frequency of class 1 integron was detected among our isolates. Results indicated that wild birds are reservoirs of multidrug resistance and virulence genes that may have the potential to be transferred to other organisms, including humans. | 2024 | 39298116 |
| 2918 | 3 | 0.9996 | Antibiotic resistance genes in multidrug-resistant Enterococcus spp. and Streptococcus spp. recovered from the indoor air of a large-scale swine-feeding operation. AIMS: In this study, multidrug-resistant bacteria previously recovered from the indoor air of a large-scale swine-feeding operation were tested for the presence of five macrolide, lincosamide and streptogramin (MLS) resistance genes and five tetracycline (tet) resistance genes. METHODS AND RESULTS: Enterococcus spp. (n = 16) and Streptococcus spp. (n =16) were analysed using DNA-DNA hybridization, polymerase chain reaction (PCR) and oligoprobing of PCR products. All isolates carried multiple MLS resistance genes, while 50% of the Enterococcus spp. and 44% of the Streptococcus spp. also carried multiple tet resistance genes. All Enterococcus spp. carried erm(A) and erm(B), 69% carried erm(F), 44% carried mef(A), 75% carried tet(M), 69% carried tet(L) and 19% carried tet(K). All Streptococcus spp. carried erm(B), 94% carried erm(F), 75% carried erm(A), 38% carried mef(A), 50% carried tet(M), 81% carried tet(L) and 13% carried tet(K). CONCLUSIONS: Multidrug resistance among airborne bacteria recovered from a swine operation is encoded by multiple MLS and tet resistance genes. These are the first data regarding resistance gene carriage among airborne bacteria from swine-feeding operations. SIGNIFICANCE AND IMPACT OF THE STUDY: The high prevalence of multiple resistance genes reported here suggests that airborne Gram-positive bacteria from swine operations may be important contributors to environmental reservoirs of resistance genes. | 2006 | 17032228 |
| 2928 | 4 | 0.9996 | Antibiotic use in infants within the first year of life is associated with the appearance of antibiotic-resistant genes in their feces. BACKGROUND: Antibiotic resistance, an increasing challenge, is not only a national threat but also a global threat. Carriage of resistance genes is not limited to adults alone, various microbiota niches present in the body system of children have been found to harbor bacteria carrying resistant genes, especially, their gut microbiota. This study aims to identify selected antibiotic-resistant genes from the fecal samples of infants and the association of antibiotics use with the occurrence of resistant genes in the infant's gut. METHODS: A total number of 172 metagenomic DNA samples previously extracted from stool samples of 28 Nigerian babies longitudinally within their first year of life were screened for the presence of ESBL genes (blaSHV, blaTEM, and blaCTX-M), PMQR genes (qnrA, qnrB, qnrS, qepA), ribosomal protection protein tetracycline resistance gene, (RPP) β-lactamase (blaZ), macrolide (ermA, ermB, mefA/E), aminoglycoside modifying enzymes gent(R) (aac(6')/aph(2″)) and dfrA genes by PCR. Nineteen (19) of the 28 babies used antibiotics during the study. The association between antibiotic use by the babies within the first year of life and occurrence of resistant genes were analyzed by Spearman rank correlation. RESULTS: One hundred and twenty-two (122) samples (71%) out of the 172 isolates had antibiotic-resistance genes. PMQR genes were absent in all the samples. Three isolates had blaTEM gene, nine isolates had blaSHV gene, six isolates had blaCTX-M gene and 19 isolates had dfrA gene, 31 samples had tet gene, 29 samples had mef gene, 27 samples had ermB gene, four samples had ermA gene, 13 samples had blaZ gene and 16 samples had aac gene. The babies whose samples had resistant genes used antibiotics in the same months the samples were collected. Interestingly, the 11 babies whose samples had the dfrA gene all used antibiotics in the same months their samples were collected but none of them used trimethoprim/sulfamethoxazole antibiotic. The overall correlation matrix of the babies showed a strong association between antibiotic use (AU) and antibiotic use presence of resistance genes (AUPRG) with a coefficient of 0.89. Antibiotic-resistant genes are present in the gut of infants and their occurrence is strongly connected with antibiotic use by infants. | 2023 | 37214087 |
| 2941 | 5 | 0.9996 | Uncovering hidden threats: prevalence, antibiotic resistance and virulence gene profiles of Escherichia coli strains isolated from Testudines and their aquatic habitats. BACKGROUND: The gut microbiota of Testudines is fundamental to their digestion and overall health, yet remains a poorly investigated area in their biology, particularly in wild freshwater turtle (terrapins) and tortoise populations within South Africa. This study investigated the occurrence, diversity, virulence genes and antibiotic resistance of Escherichia coli isolated from Testudine gut microbiota and sediments at Timbavati Private Nature Reserve, South Africa. METHODS AND RESULTS: Cloacal swab samples were collected from 36 wild Testudines and 20 sediment samples from temporary and permanent water bodies. Presumed E. coli isolates were confirmed by polymerase chain reaction (PCR) targeting the β-D glucuronidase (uidA) gene and further validated through 16 S rRNA gene sequencing. Phenotypic antibiotic resistance was evaluated with the Kirby-Bauer method, whilst resistance and virulence genes were identified using PCR assays. E. coli was detected in 54 (62%) of 87 isolates (23 Testudines and 31 sediments), confirmed by uidA PCR assay. Detected virulence genes included eaeA (42%), virF (22%), stx1 (16%), and stx2 (3%), and isolates exhibited resistance to erythromycin (53%), cephalothin (48%), and spectinomycin (40%). Resistance genes such as mcr-4 (70%), bla(SHV) (46%), bla(TEM) (64%), mcr-1 (42%), qnrA (16%), mcr-2 (22%), qnrD (11%), and tetW (2%) were also detected. CONCLUSIONS: This study demonstrates that wild Testudines harbour E. coli in their gut and that it also occurs in their surrounding environment, with notable antibiotic resistance and virulence potential. The findings underscore the complexity of host-microbial interactions and the influence of environmental and host factors on microbial diversity, informing potential conservation and health management strategies for these reptilian species. | 2025 | 40751752 |
| 2904 | 6 | 0.9996 | The maintenance in the oral cavity of children of tetracycline-resistant bacteria and the genes encoding such resistance. OBJECTIVES: To investigate the maintenance of tetracycline-resistant oral bacteria and the genes encoding tetracycline resistance in these bacteria in children (aged 4--6 years) over a period of 12 months. METHODS: Plaque and saliva samples were taken from 26 children. Tetracycline-resistant bacteria were isolated and identified. The types of resistance genes and their genetic locations were also determined. RESULTS: Fifteen out of 18 children harboured tetracycline-resistant (defined as having a MIC>or=8 mg/L) oral bacteria at all three time points. The median percentage of tetracycline-resistant bacteria at 0, 6 and 12 months was 1.37, 1.37 and 0.85%, respectively; these were not significantly different. The MIC(50) of the group was 64 mg/L at all three time points compared with the MIC(90), which was 64 mg/L at 0 months, and 128 mg/L at 6 and 12 months. The most prevalent resistant species were streptococci (68%), which were isolated at all three time points in 13 children. The most prevalent gene encoding tetracycline resistance was tet(M) and this was found in different species at all three time points. For the first time, tet(32) was found in Streptococcus parasanguinis and Eubacterium saburreum. PCR and Southern-blot analysis (on isolates from three of the children) showed that the tet(M) gene was located on a Tn916-like element and could be detected at all three time points, in four different genera, Streptococcus, Granulicatella, Veillonella and Neisseria. CONCLUSIONS: The results of this study show that tetracycline-resistant bacteria and tet(M) are maintained within the indigenous oral microbiota of children, even though they are unlikely to have been directly exposed to tetracycline. | 2005 | 16027144 |
| 2979 | 7 | 0.9996 | Quinolone-resistant Escherichia coli in Poultry Farming. Increasing bacterial resistance to quinolone antibiotics is apparent in both humans and animals. For humans, a potential source of resistant bacteria may be animals or their products entering the human food chain, for example poultry. Between July 2013 and September 2014, samples were collected and analyzed in the Moravian regions of the Czech Republic to isolate the bacterium Escherichia coli. As a result, 212 E. coli isolates were obtained comprising 126 environmental isolates from poultry houses and 86 isolates from cloacal swabs from market-weight turkeys. Subsequently, the E. coli isolates were tested for susceptibility to selected antibiotics. Resistance of the poultry isolates to quinolones ranged from 53% to 73%. Additionally, the presence of plasmid-mediated resistance genes was studied. The genes were confirmed in 58% of the tested strains. The data on resistance of isolates from poultry were compared with results of resistance tests in human isolates obtained in the same regions. The high levels of resistance determined by both phenotyping and genotyping methods and reported in the present study confirm the fact that the use of fluoroquinolones in poultry should be closely monitored. | 2017 | 28662329 |
| 2895 | 8 | 0.9996 | Diversity of antimicrobial resistance genes and class-1-integrons in phylogenetically related porcine and human Escherichia coli. Antimicrobial resistant bacteria and resistance genes can be transferred between the microbial flora of humans and animals. To assess the dimension of this risk, we compared the phylogenetic ancestry of human and porcine tetracycline-insusceptible Escherichia coli. Further, we compared the resistance gene profiles (tetA/tetB/tetC/tetD/tetM/sulI/sulII/sulIII/strA-strB/addA) and the prevalence of class-1-integrons in isolates of identical and different phylogroups by endpoint-PCR. This is the first genotypic comparison of antimicrobial resistance in E. coli from humans and animals which allows for the phylogenetic ancestry of the isolates. E. coli isolates from diseased humans belonged regularly to phylogroup B2 (24.3%) or D (30.9%) and were rarely not typeable (7.2%); by contrast, isolates from pig manure were regularly not typeable (46.7%) and rarely grouped into phylogroup B2 (2.2%) or D (2.9%). Class-1-integrons were detected in 40.8% of clinical (n=152), in 9.5% of community-derived (n=21) and in 10.9% of porcine (n=137) E. coli. The prevalence of sulI (42.4%/16.0%) in phylogroup A and of tetA, tetB and sulII in phylogroup B1 differed significantly between human clinical and porcine strains. Human clinical isolates (except B2-isolates) carried significantly more different resistance genes per strain, compared to porcine or community-derived isolates. ERIC-PCR-analysis of B2- (and D-) isolates with identical genetic profiles revealed that only a minor part was clonally related. The dominant resistance gene profiles differed depending on phylogroup and source. Human and porcine isolates do not exceedingly share their genes, and might rapidly adapt their resistance gene equipment to meet the requirements of a new environment. The study underlines that resistance gene transfer between human and porcine isolates is limited, even in phylogenetically related isolates. | 2012 | 22854332 |
| 2387 | 9 | 0.9996 | Phenotypic and genotypic antimicrobial resistance profiles of fecal lactobacilli from domesticated pigeons in Poland. Lactobacillus species play an important role in the host and although they are non-pathogenic, they could act as reservoirs for antibiotic resistance genes, with the potential risk of transfer to other bacteria inhabiting the gastrointestinal tract. The aim of this study was to identify Lactobacillus species derived from feces of domesticated pigeons and to characterize their phenotypic and genotypic antimicrobial resistance (AMR) profiles. A total of 57 Lactobacillus isolates were classified into six species using the MALDI-TOF technique and 16S rDNA restriction analysis. Strains of L. ingluviei (31%), L. salivarius (28%) and L. agilis (23%) were the dominant species isolated. Determination of antimicrobial susceptibility by the microdilution broth method showed widespread resistance to kanamycin (89%), tetracycline (84%), streptomycin (63%), and enrofloxacin (37%). Less than 30% of the isolates were resistant to erythromycin, lincosamides, gentamycin, chloramphenicol and vancomycin. Over half (51%) of the lactobacilli were classified as multidrug resistant. Tet genes were detected in 79% of isolates; the lnuA, cat, ermB, ermC, ant(6)-Ia, ant(4')-Ia, and int-Tn genes were found at a lower frequency. Sequence analysis of the quinolone resistance-determining region (QRDR)of the gyrA gene showed that fluoroquinolone resistance in lactobacilli was the result of a mutation that lead to a change in the amino acid sequence (Ser83→Tyr/Leu/Phe). Domesticated pigeons could be a reservoir for AMR Lactobacillus strains and AMR genes. | 2020 | 32781109 |
| 2939 | 10 | 0.9996 | Antimicrobial Resistance Genes in Pigeons from Public Parks in Costa Rica. Antimicrobial resistance is known to be an emerging problem, but the extent of the issue remains incomplete. The aim of this study was to determine the presence or absence of nine resistance genes (bla(TEM) , catI, mecA, qnrS, sulI, sulII, tet(A), tet(Q), vanA) in the faeces of 141 pigeons from four urban parks in Alajuela, Guadalupe, Tres Ríos and San José in Costa Rica. The genes were identified by real-time PCR directly from enema samples. About 30% of the samples were positive for genes catI and sulI; between 13% and 17% were positive for qnrS, sulII, tet(A) and tet(Q); and 4% were positive for bla(TEM) . The mecA and vanA genes were not detected. The average of antimicrobial resistance genes detected per pigeon was 2. Eight different patterns of resistance were identified, without differences in the sampling areas, being the most common pattern 2 (sulII positive samples). During rainy season, the genes more frequently found were sulI and tet(A). In conclusion, the urban inhabiting pigeons tested are currently carrying antimicrobial resistance genes, potentially acting as reservoirs of resistant bacteria and vectors to humans. To the authors' knowledge, this is the first study carried out on direct detection of resistance genes in the digestive metagenomes of pigeons. | 2017 | 28233464 |
| 2693 | 11 | 0.9996 | Prevalence, Antimicrobial Resistance and Toxin-Encoding Genes of Clostridioides difficile from Environmental Sources Contaminated by Feces. Clostridioides difficile (C. difficile) is the most common pathogen causing antibiotic-associated intestinal diseases in humans and some animal species, but it can also be present in various environments outside hospitals. Thus, the objective of this study was to investigate the presence and the characteristics of toxin-encoding genes and antimicrobial resistance of C. difficile isolates from different environmental sources. C. difficile was found in 32 out of 81 samples (39.50%) after selective enrichment of spore-forming bacteria and in 45 samples (55.56%) using a TaqMan-based qPCR assay. A total of 169 C. difficile isolates were recovered from those 32 C. difficile-positive environmental samples. The majority of environmental C. difficile isolates were toxigenic, with many (88.75%) positive for tcdA and tcdB. Seventy-four isolates (43.78%) were positive for binary toxins, cdtA and cdtB, and 19 isolates were non-toxigenic. All the environmental C. difficile isolates were susceptible to vancomycin and metronidazole, and most isolates were resistant to ciprofloxacin (66.86%) and clindamycin (46.15%), followed by moxifloxacin (13.02%) and tetracycline (4.73%). Seventy-five isolates (44.38%) showed resistance to at least two of the tested antimicrobials. C. difficile strains are commonly present in various environmental sources contaminated by feces and could be a potential source of community-associated C. difficile infections. | 2023 | 36671363 |
| 2921 | 12 | 0.9996 | Diversity of tetracycline resistance genes in bacteria from aquaculture sources in Australia. AIMS: To determine the genetic determinants responsible for tetracycline resistance in oxytetracycline resistant bacteria from aquaculture sources in Australia. METHODS AND RESULTS: Twenty of 104 (19%) isolates tested were resistant to oxytetracycline (MIC > or = 16 microg ml(-1)). Using polymerase chain reaction (PCR) amplification, one or more tet genes were detected in 15/20 (75%) isolates tested, but none were found in 5/20 (25%). tetM (50%) was the most common determinant, followed by tetE (45%), tetA (35%) and tetD (15%). Five of 12 oxytetracycline resistant isolates studied were able to transfer their R-plasmid to Escherichia coli recipients of chicken, pig and human origin. tetA, tetD and tetM were found to be transferred while tetE was not transferred. Southern hybridization and PCR were used to confirm transfer of determinants. CONCLUSIONS: Bacterial isolates from aquaculture sources in Australia harbour a variety of tetracycline resistance genes, which can be transferred to other bacteria of different origin. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacteria from aquaculture sources in Australia contribute to the resistance gene pool reservoir. The in vitro transfer of tetracycline R-plasmid from aquatic bacteria to E. coli isolates from various sources is an indication of the potential public health risk associated with these resistance determinants. | 2007 | 17953612 |
| 2330 | 13 | 0.9996 | Antimicrobial and disinfectant resistance of Escherichia coli isolated from giant pandas. AIMS: The study aims to demonstrate the antimicrobial and disinfectant resistance phenotypes and genotypes of Escherichia coli isolates obtained from giant pandas (Ailuropoda melanoleuca). METHODS AND RESULTS: Antimicrobial testing was performed according to the standard disk diffusion method. The minimal inhibitory concentrations (MICs) of disinfectants were determined using the agar dilution method. All isolates were screened for the presence of antimicrobial and disinfectant resistance genes and further analysed for genetic relatedness by pulse-field gel electrophoresis (PFGE). Results showed that 46·6% of the isolates were resistant to at least one antimicrobial. Escherichia coli isolates showed resistance to fewer antimicrobials as panda age increased. Among antimicrobial-resistant E. coli isolates, the antimicrobial resistance genes blaCTX-M (88·2%) and sul1 (92·3%) were most prevalent. The disinfectant resistance genes emrE, ydgE/ydgF, mdfA and sugE(c) were commonly present (68·2-98·9%), whereas qac and sugE(p) were relatively less prevalent (0-21·3%). The frequencies of resistance genes tended to be higher in E. coli isolated in December than in July, and PFGE profiles were also more diverse in isolates in December. The qacEΔ1 and sugE(p) genes were higher in adolescent pandas than in any other age groups. PFGE revealed that antimicrobial resistance correlated well with sampling time and habitat. CONCLUSIONS: This study demonstrated that antimicrobial and disinfectant resistance was common in giant panda-derived E. coli, and the antimicrobial resistance was associated with sampling time and habitat. Escherichia coli could serve as a critical vector in spreading disinfectant and antimicrobial resistance. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study that demonstrated the phenotypic and genetic characterizations of antimicrobial and disinfectant resistance in E. coli isolates from more than 60 giant pandas. Frequent transfer of pandas to other cages may lead to the dissemination of antimicrobial resistance. The study highlights the need for regularly monitoring the antimicrobial and disinfectant resistance in bacteria from giant pandas. | 2015 | 25846200 |
| 2736 | 14 | 0.9996 | Characterization of Bacterial Communities and Their Antibiotic Resistance Profiles in Wastewaters Obtained from Pharmaceutical Facilities in Lagos and Ogun States, Nigeria. In Nigeria, pharmaceutical wastewaters are routinely disseminated in river waters; this could be associated with public health risk to humans and animals. In this study, we characterized antibiotic resistant bacteria (ARB) and their antibiotic resistance profile as well as screening for sul1 and sul2 genes in pharmaceutical wastewater effluents. Bacterial composition of the wastewater sources was isolated on non-selective media and characterized by the polymerase chain reaction (PCR) amplification of the 16S rRNA genes, with subsequent grouping using restriction fragment length polymorphism (RFLP) and sequencing. The antibiotics sensitivity profiles were investigated using the standard disk diffusion plate method and the minimum inhibitory concentrations (MICs) of selected antibiotics on the bacterial isolates. A total of 254 bacterial strains were isolated, and majority of the isolates were identified as Acinetobacter sp., Klebsiella pneumonia, Proteus mirabilis, Enterobacter sp. and Bacillus sp. A total of 218 (85.8%) of the bacterial isolates were multidrug resistant. High MICs values were observed for all antibiotics used in the study. The result showed that 31.7%, 21.7% and 43.3% of the bacterial isolates harbored sul1, sul2, and Intl1 genes, respectively. Pharmaceuticals wastewaters are potential reservoirs of ARBs which may harbor resistance genes with possible risk to public health. | 2018 | 29966226 |
| 2908 | 15 | 0.9996 | Detection of tetracycline and macrolide resistance determinants in Enterococci of animal and environmental origin using multiplex PCR. An occurrence of resistance to tetracycline (TET) and erythromycin (ERY) was ascertained in 82 isolates of Enterococcus spp. of animal and environmental origin. Using E test, 33 isolates were resistant to TET and three isolates to ERY. Using polymerase chain reaction (PCR; single and multiplex), the TET determinants tet(M) and tet(L) were detected in 35 and 13 isolates, respectively. Twelve isolates carried both tet(M) and tet(L) genes. Eight isolates possessed ermB gene associated with ERY resistance. Multiplex PCR was shown to be a suitable method for simultaneous determination of all three resistance determinants that occurred most frequently in bacteria isolated from poultry. This study also demonstrates that gastrointestinal tract of broilers may be a reservoir of enterococci with acquired resistance to both TET and ERY that can be transferred to humans via food chain. | 2011 | 21656006 |
| 2910 | 16 | 0.9996 | Phenotypic and genotypic characterization of tetracycline and minocycline resistance in Clostridium perfringens. The aim of this study was to determine the incidence of tetracycline resistance and the prevalence of tetracycline-resistance genes in strains of Clostridium perfringens isolated from different sources between 1994 and 2005. Susceptibility to tetracycline and minocycline in strains from humans (35 isolates), chickens (15 isolates), food (21 isolates), soil (16 isolates) and veterinary sources (6 isolates) was determined, and tetracycline-resistance genes were detected. Resistance was most common in strains isolated from chickens, followed by those from soils, clinical samples and foods. The most highly resistant strains were found among clinical and food isolates. tetA(P) was the most common resistance gene, and along with tetB(P) was found in all resistant strains and some sensitive strains. One tetracycline-resistant food isolate had an intact tet(M) gene. However, PCR fragments of 0.4 or 0.8 kb with high degrees of identity to parts of the tet(M) sequences of other bacteria were found, mainly in clinical isolates, and often in isolates with tetB(P). No correlation between level of sensitivity to tetracycline or minocycline and the presence of tetA(P), tetB(P) or part of tet(M) was found. The presence of part of tet(M) in some strains of C. perfringens containing tetB(P) may have occurred by recent gene transfer. | 2010 | 20661548 |
| 2840 | 17 | 0.9996 | Resistome analysis of Escherichia coli isolates from layers in Hungary. The authors aimed to investigate eight strains of Escherichia coli (E. coli) strains from Hungarian layer flocks for antimicrobial resistance genes (ARG), using metagenomic methods. The strains were isolated from cloacal swabs of healthy adult layers. This study employed shotgun sequencing-based genetic and bioinformatic analysis along with determining phenotypic minimum inhibitory concentrations. A total of 59 ARGs were identified in the eight E. coli isolates, carrying ARGs against 15 groups of antibiotics. Among these, 28 ARGs were identified as transferable. Specifically, four ARGs were plasmid-derived, 18 ARGs were phage-derived and an additional six ARGs were predicted to be mobile, contributing to their mobility and potential spread between bacteria. | 2024 | 38578711 |
| 2735 | 18 | 0.9996 | Insight into the Antibiotic Resistance of Bacteria Isolated from Popular Aquatic Products Collected in Zhejiang, China. The present study was aimed to obtain a close insight into the distribution and diversity of antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) among the aquatic products collected in Zhejiang, China. A total of 136 presumptive ARB picked up from six aquatic samples were classified into 22 genera and 49 species based on the 16S rDNA sequencing. Aeromonas spp., Shewanella spp., Acinetobacter spp., Myroides spp., Pseudomonas spp., and Citrobacter spp. accounted for 80% of the ARB. Among them, 109 isolates (80.15%) exhibited resistance to at least one antibiotic. Most isolates showed resistance to not only the originally selected drug but also to one to three other tested drugs. The diversity of ARB distributed in different aquatic products was significant. Furthermore, the resistance data obtained from genotypic tests were not entirely consistent with the results of the phenotypic evaluation. The genes qnrS, tetA, floR, and cmlA were frequently detected in their corresponding phenotypic resistant isolates. In contrast, the genes sul2, aac(6')-Ib, and bla (PSE) were less frequently found in the corresponding phenotypically resistant strains. The high diversity and detection rate of ARB and ARGs in aquaculture might be a significant threat to the food chains closely related to human health. | 2023 | 36929890 |
| 2905 | 19 | 0.9996 | Scarce detection of mobile erm genes associated with tetQ in Bacteroides and Parabacteroides from Costa Rica. The frequency of finding of clindamycin-resistant anaerobic bacteria in clinical samples has doubled from 2008 to 2010 in Costa Rica. To determine whether this increase is due to dissemination of erm genes aided by tetQ elements, we analyzed 100 isolates of Bacteroides or Parabacteroides from a regional hospital, a national hospital, and the community. Antimicrobial susceptibilities were recorded with a broth micro-dilution method and erm genes were detected by PCR and Southern blotting. In addition, plasmid isolation and mating experiments were performed to clarify the location and mobility of the detected erm genes. Resistance to clindamycin was by far more frequent in the regional hospital (72%) than in the national hospital (29%) and the community (26%). Resistance to tetracycline was even more common, with the community (85%) outweighing the hospitals (71-72%). While MIC of clindamycin were higher in the hospitals than in the community (P < 0.05), the opposite was seen for tetracycline (P < 0.0001). Of the sought-after genes, only ermG (n = 2), ermA (n = 1), and ermF (n = 1) were detected in the hospitals and ermF in the community (n = 2). In opposition to the low frequency of finding of erm genes, 71% of the isolates were positive for tetQ. None of the detected genes were encoded on plasmids. Only three isolates from the hospitals transferred their erm genes laterally. By contrast, 13 hospital isolates and two community isolates transferred tetQ. Despite the widespread finding of tetracycline-resistant tetQ-positive bacteria, mobile erm genes were rare in our bacterial collection. We conclude that the detected erm genes are likely not included in typical conjugative transposons of Bacteroides and Parabacteroides. | 2013 | 23528984 |