# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 1343 | 0 | 1.0000 | Profiling toxin genes and antibiotic resistance in Bacillus cereus isolated from pre-launch spacecraft. Characterization of the microbiomes of pre-launch spacecraft in spacecraft assembly facilities is an important step in keeping crews healthy during journeys that can last several hundred days in small artificial environments in space. Bacillus cereus, a foodborne pathogenic bacterium, has the potential to be a significant source of food contamination in such environments. This bacterium is a spore-forming bacteria that resists different antimicrobial treatments in cleanrooms where spacecraft are assembled. This study evaluated 41 B. cereus isolates from four pre-launch spacecraft in spacecraft assembly facilities for their toxin gene profile and antibiotic resistance. Four enterotoxin genes (hlbC, cytK, nheA, and entFM) and two emetic toxin genes (ces and CER) were targeted for chromosomal DNA and plasmid DNA. Results showed 31.7, 7.3, 85, and 41.5% of isolates contained hblC, cytK, nheA, and entFM, respectively, in chromosomal or plasmid DNA. Overall, 37 isolates (90.2%) showed at least one enterotoxin gene. The emetic toxin gene, ces, was detected in the plasmid DNA of three isolates (7.3%). The antibiotic resistance of isolates was evaluated by the Kirby-Bauer disk diffusion procedure. All the isolates exhibited 100% susceptibility to gentamicin, 97% were susceptible to clindamycin, and 95% to chloramphenicol, imipenem, tetracycline, and vancomycin. The overall susceptibility average is 51%. However, 98% of the isolates were resistant to β-lactam antibiotics, 97.5% were resistant to sulfamethoxazole/trimethoprim, and 80% were resistant to rifampin. This study provides important information on B. cereus isolates from spacecraft assembly facilities for use in microbial monitoring programs of spacecraft. | 2023 | 38045028 |
| 2713 | 1 | 0.9995 | Identification of Escherichia coli from broiler chickens in Jordan, their antimicrobial resistance, gene characterization and the associated risk factors. BACKGROUND: Avian pathogenic Escherichia coli (APEC) is the principle cause of colibacillosis affecting poultry. The main challenge to the poultry industry is antimicrobial resistance and the emergence of multidrug resistant bacteria that threaten the safety of the food chain. Risk factors associated with emergence of antimicrobial resistance among avian pathogenic E. coli were correlated with the inappropriate use of antimicrobials along with inadequate hygienic practices, which encourages the selection pressure of antimicrobial resistant APEC. The aim of this study was to isolate, identify, serogroup and genotype APEC from broilers, assess their antibiotic resistance profile, expressed genes and the associated risk factors. RESULTS: APEC was isolated from the visceral organs of sick chickens with a prevalence of 53.4%. The most prevalent serotypes were O1, O2, O25 and O78, in percentage of 14.8, 12.6, 4.4 and 23.7%, respectively. Virulence Associated Genes; SitA, iss, iucD, iucC, astA, tsh cvi and irp2 were detected in rate of 97.4, 93.3, 75, 74, 71, 46.5, 39 and 34%, respectively and 186 (69.2%) isolates possess > 5-10 genes. The highest resistance was found against sulphamethoxazole-trimethoprim, florfenicol, amoxicillin, doxycycline and spectinomycin in percentage; 95.5, 93.7, 93.3, 92.2 and 92.2%, respectively. Sixty-eight percent of APEC isolates were found to have at least 5 out of 8 antimicrobial resistant genes. The most predominant genes were Int1 97%, tetA 78.4%, bla TEM 72.9%, Sul1 72.4%, Sul2 70.2%. Two risk factors were found to be associated with the presence of multi-drug resistant APEC in broiler chickens, with a P value ≤0.05; the use of ground water as source of drinking water and farms located in proximity to other farms. CONCLUSIONS: This study characterized the VAGs of avian pathogenic E. coli and establish their antimicrobial resistance patterns. The widespread of antimicrobial resistance of APEC isolates and detection of ARGs highlighted the need to monitor the spread of ARGs in poultry farms and the environment in Jordan. Use of ground water and closely located farms were significant risk factors associated with the presence of MDR APEC in broiler chickens in Jordan. | 2019 | 31118039 |
| 2710 | 2 | 0.9995 | Isolation and molecular characterization of multidrug‑resistant Escherichia coli from chicken meat. Antibiotics in animal farms play a significant role in the proliferation and spread of antibiotic-resistant genes (ARGs) and antibiotic-resistant bacteria (ARB). The dissemination of antibiotic resistance from animal facilities to the nearby environment has become an emerging concern. The present study was focused on the isolation and molecular identification of Escherichia coli (E. coli) isolates from broiler chicken meat and further access their antibiotic-resistant profile against different antibiotics. Broiler chicken meat samples were collected from 44 retail poultry slaughter shops in Prayagraj district, Uttar Pradesh, India. Standard bacteriological protocols were followed to first isolate the E. coli, and molecular characterization was performed with genus-specific PCR. Phenotypic and genotypic antibiotic-resistant profiles of all confirmed 154 E. coli isolates were screened against 09 antibiotics using the disc diffusion and PCR-based method for selected resistance genes. In antibiotic sensitivity testing, the isolates have shown maximum resistance potential against tetracycline (78%), ciprofloxacin (57.8%), trimethoprim (54.00%) and erythromycin (49.35%). E. coli bacterial isolates have shown relative resistant to amoxicillin-clavulanic acid (43.00%) and against ampicillin (44.15%). Notably, 64.28% E. coli bacteria were found to be multidrug resistant. The results of PCR assays exposed that tetA and blaTEM genes were the most abundant genes harboured by 83 (84.0%) and 82 (82.0%) out of all 99 targeted E. coli isolates, followed by 48.0% for AmpC (CITM) gene and cmlA (23.00%) for chloramphenicol resistance. It is notable that most of the isolates collected from chicken meat samples were multidrug resistant (> 3 antibiotics), with more than 80% of them carrying tetracycline (tetA) and beta-lactam gene (blaTEM). This study highlights the high risk associated with poultry products due to MDR-E. coli and promote the limited use of antibiotics in poultry farms. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-024-03950-7. | 2024 | 38476645 |
| 2709 | 3 | 0.9995 | Isolation, genotyping and antibiotic resistance analysis in Salmonella species isolated from turkey meat in Isfahan, Iran. Salmonella is one of the mainzoonotic bacteria in the poultry industry.The knowledge about biological characteristics and antibiotic resistance pattern can help medication in poultry and human. This research aimed to study Salmonella spp contamination and its antibiotic resistance in turkey meat in Isfahan province, Iran.400 samples were collected from the turkey meat in slaughter line (May 2021 to May 2022). The conventional microbiological and biochemical tests were applied for isolation and typing of Salmonella spp. The polymerase chain reaction (PCR) was utilized for detection and typing of Salmonella strains. The antibiotic sensitivity test was achieved and all strains were evaluated for resistance genes of Act (3)-IV, Sul1 and qnrA. In microbiological examination, 32 Salmonella strains (8 %) were identified. All tested strains were positive for invA gene. By amplifying the FlicC and Prot6E genes, 28 and 4 strains had genes related to enteritidis and typhimurium, respectively. In disc diffusion test, the highest antibiotic resistance was to oxytetracycline (50 %) and the lowest was to gentamicin, amoxiclavulanic acid, cefotaxime and ceftriaxone. The results showed that 6 (18.75 %) and 10 (31.25 %) of the Salmonella spp were able to amplify Sul1 and qnrA genes, respectively. No Salmonella strain could amplify Act (3)-IV gene. 100 % of the strains carried the Sul1 and qnrA genes were resistant to sulfonamide, and enrofloxacin. Furthermore, 3 sulfonamide resistant strains (75 %) and 5 enrofloxacin resistant strains (83.33 %) were harbored Sul1 and qnrA genes, respectively. The prevalence and antibiotic resistance of Salmonella spp in turkey meat can induce health risk concern. However, the wide spectrum antibiotic resistance complicates the proper treatment of Salmonella infection in human. | 2025 | 39944349 |
| 1284 | 4 | 0.9995 | Research Note: Molecular characterization of antimicrobial resistance and virulence gene analysis of Enterococcus faecalis in poultry in Tai'an, China. Enterococcus faecalis (E. faecalis) is a zoonotic pathogen that causes severe economic losses in the poultry-breeding industry. In our study, cecal samples from broilers with cecal enlargement at slaughterhouses in Tai'an, China, were analyzed. The results revealed that the 61 E. faecalis strains had drug resistance rates ranging from 96.72 to 8.20% against 11 antibiotics in 5 classes, of which erythromycin (96.72%) and tetracycline (96.72%) had the highest rates and vancomycin (8.20%) the lowest. The highest detection rate of multiple drug-resistant strains in 61 isolates was 72.13%. The results of polymerase chain reaction showed that, of the 12 virulence genes, ccf had the highest detection rate (80.33%), followed by asal and cob (both 78.69%), whereas hyl had the lowest (6.56%). Among 15 drug resistance genes, ermB had the highest detection rate (95.08%), followed by tetM (91.80%) and tetL (90.16%), whereas tetK (0.00%) and vanB (0.00%) remained undetected. Of the 34 sequence types found with multilocus sequence typing, the most predominant were ST631 (13.11%, 8/61) and ST634 (8.2%, 5/61). Our results provide a theoretical basis for guiding the rational use of antibiotics and preventing the spread of drug-resistant bacteria, along with epidemiological data for the risk analysis of food-borne bacteria and antimicrobial resistance in poultry farms in Shandong Province. | 2022 | 35263706 |
| 2670 | 5 | 0.9995 | Molecular characterisation and antimicrobial resistance of Streptococcus agalactiae isolates from dairy farms in China. INTRODUCTION: Streptococcus agalactiae (S. agalactiae) is a pathogen causing bovine mastitis that results in considerable economic losses in the livestock sector. To understand the distribution and drug resistance characteristics of S. agalactiae from dairy cow mastitis cases in China, multilocus sequence typing (MLST) was carried out and the serotypes and drug resistance characteristics of the bacteria in the region were analysed. MATERIAL AND METHODS: A total of 21 strains of bovine S. agalactiae were characterised based on MLST, molecular serotyping, antimicrobial susceptibility testing, and the presence of drug resistance genes. RESULTS: The serotypes were mainly Ia and II, accounting for 47.6% and 42.9% of all serotypes, respectively. Five sequence types (STs) were identified through MLST. The ST103 and ST1878 strains were predominant, with rates of 52.4% and 28.6%, respectively. The latter is a novel, previously uncharacterised sequence type. More than 90% of S. agalactiae strains were susceptible to penicillin, oxacillin, cephalothin, ceftiofur, gentamicin, florfenicol and sulfamethoxazole. The bacteria showed high resistance to tetracycline (85.7%), clindamycin (52.1%) and erythromycin (47.6%). Resistant genes were detected by PCR, the result of which showed that 47.6%, 33.3% and 38.1% of isolates carried the tet(M), tet(O) and erm(B) genes, respectively. CONCLUSION: The results of this study indicate that S. agalactiae show a high level of antimicrobial resistance. It is necessary to monitor the pathogens of mastitis to prevent the transmission of these bacteria. | 2023 | 38143824 |
| 2718 | 6 | 0.9994 | Virulence-Associated Genes and Antimicrobial Resistance of Aeromonas hydrophila Isolates from Animal, Food, and Human Sources in Brazil. Aeromonads are natural inhabitants of aquatic environments and may be associated with various human or animal diseases. Its pathogenicity is complex and multifactorial and is associated with many virulence factors. In this study, 110 selected Aeromonas hydrophila isolates isolated from food, animals, and human clinical material from 2010 to 2015 were analyzed. Antimicrobial susceptibility testing was performed by the disk diffusion method, and polymerase chain reaction was conducted to investigate the virulence genes hemolysin (hlyA), cytotoxic enterotoxin (act), heat-labile cytotonic enterotoxin (alt), aerolysin (aerA), and DNase-nuclease (exu). At least 92.7% of the isolates had one of the investigated virulence genes. Twenty different virulence profiles among the isolates were recognized, and the five investigated virulence genes were observed in four isolates. Human source isolates showed greater diversity than food and animal sources. Antimicrobial resistance was observed in 46.4% of the isolates, and multidrug resistance was detected in 3.6% of the isolates. Among the 120 isolates, 45% were resistant to cefoxitin; 23.5% to nalidixic acid; 16.6% to tetracycline; 13.7% to cefotaxime and imipenem; 11.8% to ceftazidime; 5.9% to amikacin, gentamicin, and sulfamethoxazole-trimethoprim; and 3.9% to ciprofloxacin and nitrofurantoin. Overall, the findings of our study indicated the presence of virulence genes and that antimicrobial resistance in A. hydrophila isolates in this study is compatible with potentially pathogenic bacteria. This information will allow us to recognize the potential risk through circulating isolates in animal health and public health and the spread through the food chain offering subsidies for appropriate sanitary actions. | 2020 | 32461959 |
| 2711 | 7 | 0.9994 | Antibiotic-resistant Escherichia coli and Salmonella spp. associated with dairy cattle and farm environment having public health significance. AIM: The present study was carried out to determine load of total bacteria, Escherichia coli and Salmonella spp. in dairy farm and its environmental components. In addition, the antibiogram profile of the isolated bacteria having public health impact was also determined along with identification of virulence and resistance genes by polymerase chain reaction (PCR) under a one-health approach. MATERIALS AND METHODS: A total of 240 samples of six types (cow dung - 15, milk - 10, milkers' hand wash - 10, soil - 10 water - 5, and vegetables - 10) were collected from four dairy farms. For enumeration, the samples were cultured onto plate count agar, eosin methylene blue, and xylose-lysine deoxycholate agar and the isolation and identification of the E. coli and Salmonella spp. were performed based on morphology, cultural, staining, and biochemical properties followed by PCR.The pathogenic strains of E. coli stx1, stx2, and rfbO157 were also identified through PCR. The isolates were subjected to antimicrobial susceptibility test against 12 commonly used antibiotics by disk diffusion method. Detection of antibiotic resistance genes ereA, tetA, tetB, and SHV were performed by PCR. RESULTS: The mean total bacterial count, E. coli and Salmonella spp. count in the samples ranged from 4.54±0.05 to 8.65±0.06, 3.62±0.07 to 7.04±0.48, and 2.52±0.08 to 5.87±0.05 log colony-forming unit/g or ml, respectively. Out of 240 samples, 180 (75%) isolates of E. coli and 136 (56.67%) isolates of Salmonella spp. were recovered through cultural and molecular tests. Among the 180 E. coli isolates, 47 (26.11%) were found positive for the presence of all the three virulent genes, of which stx1 was the most prevalent (13.33%). Only three isolates were identified as enterohemorrhagic E. coli. Antibiotic sensitivity test revealed that both E. coli and Salmonella spp. were found highly resistant to azithromycin, tetracycline, erythromycin, oxytetracycline, and ertapenem and susceptible to gentamycin, ciprofloxacin, and imipenem. Among the four antibiotic resistance genes, the most observable was tetA (80.51-84.74%) in E. coli and Salmonella spp. and SHV genes were the lowest one (22.06-25%). CONCLUSION: Dairy farm and their environmental components carry antibiotic-resistant pathogenic E. coli and Salmonella spp. that are potential threat for human health which requires a one-health approach to combat the threat. | 2019 | 31528022 |
| 2671 | 8 | 0.9994 | Toxinotyping and molecular characterization of antimicrobial resistance in Clostridium perfringens isolated from different sources of livestock and poultry. The present study was designed to understand the presence of antimicrobial resistance among the prevalent toxinotypes of Clostridium perfringens recovered from different animals of Tamil Nadu, India. A total of 75 (10.76%) C. perfringens were isolated from 697 multi-species fecal and intestinal content samples. C. perfringens type A (90.67%), type C (2.67%), type D (4%) and type F (2.67%) were recovered. Maximum number of isolates were recovered from dog (n = 20, 24.10%) followed by chicken (n = 19, 5.88%). Recovered isolates were resistant to gentamicin (44.00%), erythromycin (40.00%), bacitracin (40.00%), and tetracycline (26.67%), phenotypically and most of the isolates were found to be resistant to multiple antimicrobials. Genotypic characterization revealed that tetracycline (41.33%), erythromycin (34.66%) and bacitracin (17.33%) resistant genes were present individually or in combination among the isolates. Combined results of phenotypic and genotypic characterization showed the highest percentage of erythromycin resistance (26.66%) among the isolates. None of the isolates showed amplification for lincomycin resistance genes. The correlation matrix analysis of genotypic resistance showed a weak positive relationship between the tetracycline and bacitracin resistance while a weak negative relationship between the tetracycline and erythromycin resistance. The present study thus reports the presence of multiple-resistance genes among C. perfringens isolates that may be involved in the dissemination of resistance to other bacteria present across species. Further insights into the genome can help to understand the mechanism involved in gene transfer so that measures can be taken to prevent the AMR spread. | 2021 | 33220406 |
| 2681 | 9 | 0.9994 | Determination of the Prevalence and Antimicrobial Resistance of Enterococcus faecalis and Enterococcus faecium Associated with Poultry in Four Districts in Zambia. The presence of antimicrobial-resistant Enterococci in poultry is a growing public health concern worldwide due to its potential for transmission to humans. The aim of this study was to determine the prevalence and patterns of antimicrobial resistance and to detect drug-resistant genes in Enterococcus faecalis and E. faecium in poultry from four districts in Zambia. Identification of Enterococci was conducted using phenotypic methods. Antimicrobial resistance was determined using the disc diffusion method and antimicrobial resistance genes were detected using polymerase chain reaction and gene-specific primers. The overall prevalence of Enterococci was 31.1% (153/492, 95% CI: 27.1-35.4). Enterococcus faecalis had a significantly higher prevalence at 37.9% (58/153, 95% CI: 30.3-46.1) compared with E. faecium, which had a prevalence of 10.5% (16/153, 95% CI: 6.3-16.7). Most of the E. faecalis and E. faecium isolates were resistant to tetracycline (66/74, 89.2%) and ampicillin and erythromycin (51/74, 68.9%). The majority of isolates were susceptible to vancomycin (72/74, 97.3%). The results show that poultry are a potential source of multidrug-resistant E. faecalis and E. faecium strains, which can be transmitted to humans. Resistance genes in the Enterococcus species can also be transmitted to pathogenic bacteria if they colonize the same poultry, thus threatening the safety of poultry production, leading to significant public health concerns. | 2023 | 37107019 |
| 5402 | 10 | 0.9994 | Microbiological Biodiversity of Regional Cow, Goat and Ewe Milk Cheeses Produced in Poland and Antibiotic Resistance of Lactic Acid Bacteria Isolated from Them. (1) Unique sensory values of traditional and regional dairy products made them more and more popular among consumers. Lactic acid bacteria naturally occurring in these products can express antibiotic resistance and be a reservoir of antibiotic resistance genes (ARG) in the environment. The aim of the study was to characterize the microbial diversity of twenty regional cheeses produced from non-pasteurized cow, goat and ewe milk, and investigate the phenotypic and genotypic antibiotic resistance (AR) of lactic acid bacteria isolated from these products. (2) Conventional microbiological methods were applied for the enumeration of lactic acid bacteria (lactobacilli and lactococci) and their isolation, and for the enumeration of Enterococcus, Staphylococcus, Enterobacteriaceae and spores. The disc diffusion method was applied for phenotypic AR. The PCR-based methods were used for strain identification, microbiological diversity of cheeses (PCR-DGGE), and for AR gene detection. (3) Among 79 LAB isolates the most frequent species were L. plantarum (n = 18), Leuc. lactis (n = 17), Lc. lactis (n = 11), Leuc. mesenteroides (n = 9) and L. pentosus (n = 8). Additionally, by using the PCR-DGGE method, DNA of L. casei was found in nine products. Lactobacilli (5.63-8.46 log cfu/g) and lactococci (6.15-8.41 log cfu/g) predominated over Enterococcus (max. 4.89 log cfu/g), Staphylococcus (max. 4.18 log cfu/g), and Enterobacteriaceae (mostly up to 4.88 log cfu/g). Analysis of phenotypic resistance to tetracycline (30 µg), erythromycin (15 µg), and chloramphenicol (30 µg) showed that 29% of LAB isolates were resistant to one antibiotic, 8%-to two, and 12%-to all tested antibiotics. Antibiotic resistance genes (AGR) for tetracycline (tet(M), tet(L), tet(W)), erythromycin (erm(B)) and chloramphenicol (cat-TC) were detected in 30 (38%), 29 (36.7%) and 33 (43.4%) LAB isolates, respectively. Among 31 LAB isolates phenotypically susceptible to all tested antibiotics, only 5 (16%) had no ARGs. (4) The results obtained in our work shed light on the potential threat posed by the widespread presence of ARGs in LAB present in regional cheeses. | 2022 | 36611776 |
| 2956 | 11 | 0.9994 | Genomic Characterization of Enterococcus hirae From Beef Cattle Feedlots and Associated Environmental Continuum. Enterococci are commensal bacteria of the gastrointestinal tract of humans, animals, and insects. They are also found in soil, water, and plant ecosystems. The presence of enterococci in human, animal, and environmental settings makes these bacteria ideal candidates to study antimicrobial resistance in the One-Health continuum. This study focused on Enterococcus hirae isolates (n = 4,601) predominantly isolated from beef production systems including bovine feces (n = 4,117, 89.5%), catch-basin water (n = 306, 66.5%), stockpiled bovine manure (n = 24, 0.5%), and natural water sources near feedlots (n = 145, 32%), and a few isolates from urban wastewater (n = 9, 0.2%) denoted as human-associated environmental samples. Antimicrobial susceptibility profiling of a subset (n = 1,319) of E. hirae isolates originating from beef production systems (n = 1,308) showed high resistance to tetracycline (65%) and erythromycin (57%) with 50.4% isolates harboring multi-drug resistance, whereas urban wastewater isolates (n = 9) were resistant to nitrofurantoin (44.5%) and tigecycline (44.5%) followed by linezolid (33.3%). Genes for tetracycline (tetL, M, S/M, and O/32/O) and macrolide resistance erm(B) were frequently found in beef production isolates. Antimicrobial resistance profiles of E. hirae isolates recovered from different environmental settings appeared to reflect the kind of antimicrobial usage in beef and human sectors. Comparative genomic analysis of E. hirae isolates showed an open pan-genome that consisted of 1,427 core genes, 358 soft core genes, 1701 shell genes, and 7,969 cloud genes. Across species comparative genomic analysis conducted on E. hirae, Enterococcus faecalis and Enterococcus faecium genomes revealed that E. hirae had unique genes associated with vitamin production, cellulose, and pectin degradation, traits which may support its adaptation to the bovine digestive tract. E. faecium and E. faecalis more frequently harbored virulence genes associated with biofilm formation, iron transport, and cell adhesion, suggesting niche specificity within these species. | 2022 | 35832805 |
| 1344 | 12 | 0.9994 | Antibiotics resistance and toxin profiles of Bacillus cereus-group isolates from fresh vegetables from German retail markets. BACKGROUND: This study aimed to evaluate the safety of raw vegetable products present on the German market regarding toxin-producing Bacillus cereus sensu lato (s.l.) group bacteria. RESULTS: A total of 147 B. cereus s.l. group strains isolated from cucumbers, carrots, herbs, salad leaves and ready-to-eat mixed salad leaves were analyzed. Their toxinogenic potential was assessed by multiplex PCR targeting the hemolysin BL (hbl) component D (hblD), non-hemolytic enterotoxin (nhe) component A (nheA), cytotoxin K-2 (cytK-2) and the cereulide (ces) toxin genes. In addition, a serological test was used to detect Hbl and Nhe toxins. On the basis of PCR and serological results, none of the strains were positive for the cereulide protein/genes, while 91.2, 83.0 and 37.4% were positive for the Hbl, Nhe and CytK toxins or their genes, respectively. Numerous strains produced multiple toxins. Generally, strains showed resistance against the β-lactam antibiotics such as penicillin G and cefotaxim (100%), as well as amoxicillin/clavulanic acid combination and ampicillin (99.3%). Most strains were susceptible to ciprofloxacin (99.3%), chloramphenicol (98.6%), amikacin (98.0%), imipenem (93.9%), erythromycin (91.8%), gentamicin (88.4%), tetracycline (76.2%) and trimethoprim/sulfamethoxazole combination (52.4%). The genomes of eight selected strains were sequenced. The toxin gene profiles detected by PCR and serological test mostly agreed with those from whole-genome sequence data. CONCLUSIONS: Our study showed that B. cereus s.l. strains encoding toxin genes occur in products sold on the German market and that these may pose a health risk to the consumer if present at elevated levels. Furthermore, a small percentage of these strains harbor antibiotic resistance genes. The presence of these bacteria in fresh produce should, therefore, be monitored to guarantee their safety. | 2019 | 31706266 |
| 5398 | 13 | 0.9994 | Characterization and transfer of antimicrobial resistance in lactic acid bacteria from fermented dairy products in China. INTRODUCTION: Lactic acid bacteria (LAB) are commonly found in foods and are also natural intestinal inhabitants in humans and most animals. However, information regarding antimicrobial resistance and the transfer of resistance genes of LAB from fermented dairy products in China is limited. METHODOLOGY: In this study, LAB isolates (n = 82) of Lactobacillus (n = 43) and Streptococcus thermophilus (n = 39) were isolated from 51 commercial fermented food samples in China. All isolates were subjected to pulsed-field gel electrophoresis (PFGE), antimicrobial susceptibility, detecting resistance genes, as well as investigating the transferability of resistance genes. RESULTS: The 43 Lactobacillus isolates yielded 24 PFGE patterns and the 34 isolates of S. thermophilus generated 32 different PFGE patterns. Among the 43 Lactobacillus strains, the most commonly observed resistance was that to streptomycin (83.7%) and gentamycin (83.7%). Among the 39 S. thermophilus strains, the most frequently observed resistance was that to streptomycin (92.3%), gentamycin (87.2%), ciprofloxacin (79.5%), and chloramphenicol (71.8%), whereas the lowest level of resistance was that against erythromycin (7.7%). Antimicrobial resistance genes for erythromycin (emrB), gentamycin (aac(6')-aph(2")), streptomycin (ant(6)), sulfamethoxazole (sulI and sulII), tetracycline (tetM and tetS) were detected in the 18 resistance LAB strains. Conjugation experiments showed that tetM from L. delbrueckii subsp. bulgaricus R6 and tetS from L. plantarum R41 were successfully transferred to L. monocytogenes by filter mating. CONCLUSIONS: LAB strains could potentially act as reservoirs of resistance genes and play an active role in the transfer of resistance to humans via the food chain. | 2019 | 32036349 |
| 2700 | 14 | 0.9994 | Prevalence of Salmonella Typhimurium and Salmonella Enteritidis isolated from poultry meat: virulence and antimicrobial-resistant genes. Salmonellosis, a zoonotic disease, is one of the leading causes of foodborne illness worldwide. It is responsible for most infections caused by consumption of contaminated food. In recent years, a significant increase in the resistance of these bacteria to common antibiotics has been observed, posing a serious threat to global public health. The aim of this study was to investigate the prevalence of virulent antibiotic-resistant Salmonella spp. strains in Iranian poultry markets. A total of 440 chicken meat samples were randomly selected from meat supply and distribution facilities in Shahrekord and tested for bacteriological contamination. After culturing and isolating the strains, identification was performed using the classical bacteriological method and PCR. To determine antibiotic resistance, a disc diffusion test was performed according to the recommendations of the French Society of Microbiology. PCR was used to detect resistance and virulence genes. Only 9% of the samples were positive for Salmonella. These were Salmonella typhimurium isolates. All Salmonella typhimurium serotypes tested positive for the rfbJ, fljB, invA and fliC genes. Resistance to TET, cotrimoxazole, NA, NIT, piperacillin/tazobactam and other antibiotics was found in 26 (72.2%), 24 (66.7%), 22 (61.1%) and 21 (58.3%) isolates, respectively. The sul1, sul2 and sul3 genes were present in 20, 12 and 4 of 24 cotrimoxazole-resistant bacteria, respectively. Chloramphenicol resistance was found in six isolates, but more isolates tested positive for the floR and cat two genes. In contrast, 2 (33%) of the cat three genes, 3 (50%) of the cmlA genes and 2 (34%) of the cmlB genes were all positive. The results of this investigation showed that Salmonella typhimurium is the most common serotype of the bacterium. This means that most of the antibiotics commonly used in the livestock and poultry industries are ineffective against most Salmonella isolates, which is important for public health. | 2023 | 37322421 |
| 1362 | 15 | 0.9994 | Distribution of phenotypic and genotypic antimicrobial resistance and virulence genes in Vibrio parahaemolyticus isolated from cultivated oysters and estuarine water. A total of 594 Vibrio parahaemolyticus isolates from cultivated oysters (n = 361) and estuarine water (n = 233) were examined for antimicrobial resistance (AMR) phenotype and genotype and virulence genes. Four hundred forty isolates (74.1%) exhibited resistance to at least one antimicrobial agent and 13.5% of the isolates were multidrug-resistant strains. Most of the V. parahaemolyticus isolates were resistant to erythromycin (54.2%), followed by sulfamethoxazole (34.7%) and trimethoprim (27.9%). The most common resistance genes were qnr (77.8%), strB (27.4%) and tet(A) (22.1%), whereas blaTEM (0.8%) was rarely found. Four isolates (0.7%) from oysters (n = 2) and estuarine water (n = 2) were positive to tdh, whereas no trh-positive isolates were observed. Significantly positive associations among AMR genes were observed. The SXT elements and class 1, 2 and 3 integrons were absent in all isolates. The results indicated that V. parahaemolyticus isolates from oysters and estuarine water were potential reservoirs of resistance determinants in the environment. This increasing threat of resistant bacteria in the environment potentially affects human health. A 'One Health' approach involved in multidisciplinary collaborations must be implemented to effectively manage antimicrobial resistance. | 2020 | 32358958 |
| 2421 | 16 | 0.9994 | Antimicrobial susceptibility test and antimicrobial resistance gene detection of extracellular enzyme bacteria isolated from tilapia (Oreochromis niloticus) for probiotic candidates. BACKGROUND AND AIM: Antimicrobial resistance (AMR) is a global problem that can increase mortality and morbidity rates and adversely affect health. Therefore, AMR control must be carried out in various sectors, including the fisheries sector, using probiotics. Bacteria can become resistant to antibiotics, including bacteria used for probiotics. This study aimed to isolate bacteria as potential producers of extracellular enzymes, phenotypic characterization, and antibiotic-resistant gene patterns. MATERIALS AND METHODS: In this study, 459 bacterial isolates were isolated from the stomach of tilapia in Indonesia. Tilapia was obtained from Sukabumi, Ciamis, Serang, Banjarnegara, Jayapura, Sorong, Manokwari Selatan, Takalar, Lampung, Batam, and Mandiangin. Enzymatic bacteria were identified. An antimicrobial susceptibility test was conducted by agar disk diffusion, and genotypic detection of encoding genes was performed using a molecular method. RESULTS: This study obtained 137 isolates (29.84%) that can produce extracellular enzymes. The highest number of E-sensitive isolates was found, including 130 isolates (94.89%). Six isolates (6/137) can produce four enzymes (amylase, protease, cellulose, and lipase), and they were sensitive to antibiotics. A total of 99 isolates can produce extracellular enzymes, and they were sensitive to antibiotics. Such isolates serve as a consortium of probiotic candidates. The isolates that are resistant to oxytetracycline (OT), erythromycin (E), tetracycline (TE), and enrofloxacin (ENR) included 15 isolates (10.95%), seven isolates (5.11%), three isolates (2.19%), and one isolate (0.73%), respectively. In addition, four isolates (2.92%) were detected as multidrug-resistant. The tet(A) gene obtained the highest result of detection of resistance genes in isolates that were intermediate and resistant to TE and OT. Isolates that serve as ENR intermediates have a high qnr(S) resistance gene. CONCLUSION: The data in this study provide the latest update that bacteria can serve as a consortium of potential probiotics with antibiotic-resistant genes for the treatment of fish. Bacteria that are intermediate to antibiotics may contain resistance genes. The results of this study will improve the policy of probiotic standards in Indonesia. | 2023 | 37042005 |
| 1363 | 17 | 0.9994 | Comparison of antimicrobial resistance and molecular characterization of Escherichia coli isolates from layer breeder farms in Korea. In Korea, 4 big layer companies that possess one grandparent and 3 parent stocks are in charge of 100% of the layer chicken industry. In this study, we investigated the antimicrobial resistance of commensal 578 E. coli isolated from 20 flocks of 4-layer breeder farms (A, B, C, and D), moreover, compared the characteristics of their resistance and virulence genes. Isolates from farms B and D showed significantly higher resistance to the β-lactam antimicrobials (amoxicillin, ampicillin, and 1st-, 2nd-, and 3rd-generation cephalosporins). However, resistance to ciprofloxacin, nalidixic acid, and tetracycline was significantly higher in the isolates from farm A (P < 0.05). Interestingly, the isolates from farm C showed significantly lower resistance to most antimicrobials tested in this study. The isolates from farms B, C, and D showed the high multiple resistance to the 3 antimicrobial classes. Furthermore, the isolates from farm A showed the highest multiple resistance against the 5 classes. Among the 412 β-lactam-resistant isolates, 123 (29.9%) carried bla(TEM-1), but the distribution was significantly different among the farms from 17.5% to 51.4% (P < 0.05). Similarly, the most prevalent tetracycline resistance gene in the isolates from farms B, C, and D was tetA (50.0-77.0%); however, the isolates from farm A showed the highest prevalence in tetB (70.6%). The distribution of quinolone (qnrB, qnrD, and qnrS) and sulfonamide (su12)-resistant genes were also significantly different among the farms but that of chloramphenicol (catA1)- and aminoglycoside (aac [3]-II, and aac [6']-Ib)-resistant genes possessed no significant difference among the farms. Moreover, the isolates from farm C showed significantly higher prevalence in virulence genes (iroN, ompT, hlyF, and iss) than the other 3 farms (P < 0.05). Furthermore, the phenotypic and genotypic characteristics of E. coli isolates were significantly different among the farms, and improved management protocols are required to control of horizontal and vertical transmission of avian disease, including the dissemination of resistant bacteria in breeder flocks. | 2022 | 34844113 |
| 2931 | 18 | 0.9994 | Molecular characterization of antibiotic resistance in Escherichia coli strains from a dairy cattle farm and its surroundings. BACKGROUND: This study describes the phenotypic and genotypic characteristics of 78 genetically different Escherichia coli recovered from air and exudate samples of a dairy cattle farm and its surroundings in Spain, in order to gain insight into the flow of antimicrobial resistance through the environment and food supply. RESULTS: Antimicrobial resistance was detected in 21.8% of the 78 E. coli isolates analyzed (resistance for at least one of the 14 agents tested). The highest resistance rates were recorded for ampicillin, nalidixic acid, trimethoprim/sulfamethoxazole and tetracycline. The resistance genes detected were as follows (antibiotic (number of resistant strains), gene (number of strains)): ampicillin (9), bla(TEM-1) (6); tetracycline (15), tet(A) (7), tet(B) (4), tet(A) + tet(B) (1); chloramphenicol (5), cmlA (2), floR (2); trimethoprim/sulfamethoxazole (10), sul2 (4), sul1 (3), sul3 (2), sul1 + sul2 (1); gentamicin-tobramycin (1), ant(2″) (1). About 14% of strains showed a multidrug-resistant phenotype and, of them, seven strains carried class 1 integrons containing predominantly the dfrA1-aadA1 array. One multidrug-resistant strain was found in both inside and outside air, suggesting that the airborne spread of multidrug-resistant bacteria from the animal housing facilities to the surroundings is feasible. CONCLUSIONS: This study gives a genetic background of the antimicrobial resistance problem in a dairy cattle farm and shows that air can act as a source for dissemination of antimicrobial-resistant bacteria. © 2016 Society of Chemical Industry. | 2017 | 26969806 |
| 2708 | 19 | 0.9994 | Occurrence, Virulence and Antimicrobial Resistance-Associated Markers in Campylobacter Species Isolated from Retail Fresh Milk and Water Samples in Two District Municipalities in the Eastern Cape Province, South Africa. Campylobacter species are among the major bacteria implicated in human gastrointestinal infections and are majorly found in faeces of domestic animals, sewage discharges and agricultural runoff. These pathogens have been implicated in diseases outbreaks through consumption of contaminated milk and water in some parts of the globe and reports on this is very scanty in the Eastern Cape Province. Hence, this study evaluated the occurrence as well as virulence and antimicrobial-associated makers of Campylobacter species recovered from milk and water samples. A total of 56 water samples and 72 raw milk samples were collected and the samples were processed for enrichment in Bolton broth and incubated for 48 h in 10% CO(2) at 42 °C under microaerobic condition. Thereafter, the enriched cultures were further processed and purified. After which, presumptive Campylobacter colonies were isolated and later confirmed by PCR using specific primers for the detection of the genus Campylobacter, target species and virulence associated genes. Antimicrobial resistance profiles of the isolates were determined by disk diffusion method against a panel of 12 antibiotics and relevant genotypic resistance genes were assessed by PCR assay. A total of 438 presumptive Campylobacter isolates were obtained; from which, 162 were identified as belonging to the genus Campylobacter of which 36.92% were obtained from water samples and 37.11% from milk samples. The 162 confirmed isolates were further delineated into four species, of which, 7.41%, 27.16% and 8.64% were identified as C. fetus, C. jejuni and C. coli respectively. Among the virulence genes screened for, the iam (32.88%) was most prevalent, followed by flgR (26.87%) gene and cdtB and cadF (5.71% each) genes. Of the 12 antibiotics tested, the highest phenotypic resistance displayed by Campylobacter isolates was against clindamycin (95.68%), while the lowest was observed against imipenem (21.47%). Other high phenotypic resistance displayed by the isolates were against erythromycin (95.06%), followed by ceftriaxone (93.21%), doxycycline (87.65%), azithromycin and ampicillin (87.04% each), tetracycline (83.33%), chloramphenicol (78.27%), ciprofloxacin (77.78%), levofloxacin (59.88%) and gentamicin (56.17%). Relevant resistance genes were assessed in the isolates that showed high phenotypic resistance, and the highest resistance gene harbored by the isolates was catII (95%) gene while VIM, KPC, Ges, bla-(OXA)-48-like, tetC, tetD, tetK, IMI and catI genes were not detected. The occurrence of this pathogen and the detection of virulence and antimicrobial resistance-associated genes in Campylobacter isolates recovered from milk/water samples position them a risk to human health. | 2020 | 32708075 |