ROXITHROMYCIN - Word Related Documents




#
Rank
Similarity
Title + Abs.
Year
PMID
012345
538700.9743Assessment of antibiotic susceptibility within lactic acid bacteria strains isolated from wine. Susceptibility to 12 antibiotics was tested in 75 unrelated lactic acid bacteria strains of wine origin of the following species: 38 Lactobacillus plantarum, 3 Lactobacillus hilgardii, 2 Lactobacillus paracasei, 1 Lactobacillus sp, 21 Oenococcus oeni, 4 Pediococcus pentosaceus, 2 Pediococcus parvulus, 1 Pediococcus acidilactici, and 3 Leuconostoc mesenteroides. The Minimal Inhibitory Concentrations of the different antibiotics that inhibited 50% of the strains of the Lactobacillus, Leuconostoc and Pediococcus genera were, respectively, the following ones: penicillin (2, < or =0.5, and < or =0.5 microg/ml), erythromycin (< or =0.5 microg/ml), chloramphenicol (4 microg/ml), ciprofloxacin (64, 8, and 128 microg/ml), vancomycin (> or =128 microg/ml), tetracycline (8, 2, and 8 microg/ml), streptomycin (256, 32, and 512 microg/ml), gentamicin (64, 4, and 128 microg/ml), kanamycin (256, 64, and 512 microg/ml), sulfamethoxazole (> or =1024 microg/ml), and trimethoprim (16 microg/ml). All 21 O. oeni showed susceptibility to erythromycin, tetracycline, rifampicin and chloramphenicol, and exhibited resistance to aminoglycosides, vancomycin, sulfamethoxazole and trimethoprim, that could represent intrinsic resistance. Differences were observed among the O. oeni strains with respect to penicillin or ciprofloxacin susceptibility. Antibiotic resistance genes were studied by PCR and sequencing, and the following genes were detected: erm(B) (one P. acidilactici), tet(M) (one L. plantarum), tet(L) (one P. parvulus), aac(6')-aph(2") (four L. plantarum, one P. parvulus, one P. pentosaceus and two O. oeni), ant(6) (one L. plantarum, and two P. parvulus), and aph(3')-IIIa (one L. plantarum and one O. oeni). This is the first time, to our knowledge, that ant(6), aph(3')-IIIa and tet(L) genes are found in Lactobacillus and Pediococcus strains and antimicrobial resistance genes are reported in O. oeni strains.200616876896
125910.9739Tetracycline resistance potential of heterotrophic bacteria isolated from freshwater fin-fish aquaculture system. AIMS: This study investigated the tetracycline resistance potential of heterotrophic bacteria isolated from twenty-four freshwater fin-fish culture ponds in Andhra Pradesh, India. METHODS AND RESULTS: A total of 261 tetracycline resistant bacteria (tetR) were recovered from pond water, pond sediment, fish gills, fish intestine, and fish feed. Bacteria with high tetracycline resistance (tetHR) (n = 30) that were resistant to tetracycline concentrations above 128  μg mL-1 were predominantly Lactococcus garvieae followed by Enterobacter spp., Lactococcus lactis, Enterobacter hormaechei, Staphylococcus arlettae, Streptococcus lutetiensis, Staphylococcus spp., Brevundimonas faecalis, Exiguobacterium profundum, Lysinibacillus spp., Stutzerimonas stutzeri, Enterobacter cloacae, and Lactococcus taiwanensis. Resistance to 1024 μg mL-1 of tetracycline was observed in L. garvieae, S. arlettae, Enterobacter spp., B. faecalis. Tet(A) (67%) was the predominant resistance gene in tetHR followed by tet(L), tet(S), tet(K), and tet(M). At similar concentrations of exposure, tetracycline procured at the farm level (69.5% potency) exhibited lower inhibition against tetHR bacteria compared to pure tetracycline (99% potency). The tetHR bacteria showed higher cross-resistance to furazolidone (100%) followed by co-trimoxazole (47.5%) and enrofloxacin (11%). CONCLUSIONS: The maximum threshold of tetracycline resistance at 1024 μg mL-1 was observed in S. arlettae, Enterobacter spp., B. faecalis, and L. garvieae and tet(A) was the major determinant found in this study.202336958862
538620.9734Antibiotic resistance of lactic acid bacteria isolated from Chinese yogurts. The aim of this study was to evaluate the susceptibility of 43 strains of lactic acid bacteria, isolated from Chinese yogurts made in different geographical areas, to 11 antibiotics (ampicillin, penicillin G, roxithromycin, chloramphenicol, tetracycline, chlortetracycline, lincomycin, kanamycin, streptomycin, neomycin, and gentamycin). The 43 isolates (18 Lactobacillus bulgaricus and 25 Streptococcus thermophilus) were identified at species level and were typed by random amplified polymorphic DNA analysis. Thirty-five genotypically different strains were detected and their antimicrobial resistance to 11 antibiotics was determined using the agar dilution method. Widespread resistance to ampicillin, chloramphenicol, chlortetracycline, tetracyclines, lincomycin, streptomycin, neomycin, and gentamycin was found among the 35 strains tested. All of the Strep. thermophilus strains tested were susceptible to penicillin G and roxithromycin, whereas 23.5 and 64.7% of Lb. bulgaricus strains, respectively, were resistant. All of the Strep. thermophilus and Lb. bulgaricus strains were found to be resistant to kanamycin. The presence of the corresponding resistance genes in the resistant isolates was investigated through PCR, with the following genes detected: tet(M) in 1 Lb. bulgaricus and 2 Strep. thermophilus isolates, ant(6) in 2 Lb. bulgaricus and 2 Strep. thermophilus isolates, and aph(3')-IIIa in 5 Lb. bulgaricus and 2 Strep. thermophilus isolates. The main threat associated with these bacteria is that they may transfer resistance genes to pathogenic bacteria, which has been a major cause of concern to human and animal health. To our knowledge, the aph(3')-IIIa and ant(6) genes were found in Lb. bulgaricus and Strep. thermophilus for the first time. Further investigations are required to analyze whether the genes identified in Lb. bulgaricus and Strep. thermophilus isolates might be horizontally transferred to other species.201222916881
774930.9729Interaction of ciprofloxacin chlorination products with bacteria in drinking water distribution systems. The interaction of ciprofloxacin chlorination products (CIP-CPs) with bacteria in drinking water distribution systems (DWDSs) was investigated. The piperazine ring of CIP was destroyed by chlorination. Among of CIP-CPs, by the bacterial role, 7.63% of the derivative with two carboxylic groups went through decarboxylation to form desethylene ciprofloxacin, and then loss of C(2)H(5)N group generated aniline compound. Furthermore, 12.3% of the aniline compound, 7.60% of chlorinated aniline compound and 1.35% of defluorinated product were bio-mineralized. Therefore, the chlorine and bacteria played synergistic effects on transformation of CIP-CPs in DWDSs, contributing to the obvious decrease of genotoxicity in effluents. Correspondingly, the TEQ(4-NQO) decreased from 667μg/L to 9.41μg/L. However, compared with DWDSs without CIP-CPs, the relative abundance of mexA and qnrS increased 1-fold in effluents and the relative abundance of qnrA and qnrB increased 3-fold in biofilms in DWDSs with CIP-CPs. mexA and qnrS positively correlated with Hyphomicrobium, Sphingomonas and Novosphingobium (p<0.05), while qnrA and qnrB positively correlated with Shewanella and Helicobacter (p<0.05), indicating the increase of antibiotic resistance genes (ARGs) came from the growth of these bacterial genera by transformation of CIP-CPs in DWDSs. These results suggested that biotransformation of antibiotics might increase ARGs risk in DWDSs.201728648729
540440.9727Characterization of tetracycline resistance lactobacilli isolated from swine intestines at western area of Taiwan. To investigate the frequency of tetracycline resistance (Tet-R) lactobacilli in pig intestines, a total of 256 pig colons were analyzed and found to contain typical colonies of Tet-R lactic acid bacteria in every sample, ranging from 3.2 × 10(3) to 6.6 × 10(5) CFU/cm(2). From these samples, a total of 159 isolates of Tet-R lactobacilli were obtained and identified as belonging to 11 species, including Lactobacillus reuteri, Lactobacillus amylovorus, Lactobacillus salivarius, Lactobacillus plantarum, Lactobacillus ruminis, Lactobacillus kefiri, Lactobacillus fermentum, Lactobacillus sakei, Lactobacillus coryniformis, Lactobacillus parabuchneri and Lactobacillus letivazi. Based on the EFSA (2008) breakpoints, all isolates, after MIC analysis, were qualified as Tet-R, from which the significant high Tet-R MIC(50) and MIC(90) values indicated an ecological distribution of Tet-R lactobacilli mostly with high resistance potency in pig colons. PCR-detection identified 5 tet genes in these isolates, the most predominant one being tet (W), followed by tet (M), (L), (K), and (Q). Their detection rates were 82.0%, 22.5%, 14.4%, 8.1% and 0.9%, respectively. Noteworthily, isolates of the same species carrying identical tet gene(s) usually had a wide different MIC values. Furthermore, strain-subtyping of these isolates by REP-PCR demonstrated a notable genotypic biodiversity % (average = 62%).201121906691
539550.9723Assessment of Antibiotic Susceptibility within Lactic Acid Bacteria and Coagulase-Negative Staphylococci Isolated from Hunan Smoked Pork, a Naturally Fermented Meat Product in China. The aim of this study was to evaluate the antibiotic susceptibility of lactic acid bacteria (LAB) and coagulase-negative staphylococci (CNS) strains isolated from naturally fermented smoked pork produced in Hunan, China. A total of 48 strains were isolated by selective medium and identified at the species level by 16S rRNA gene sequencing as follows: Staphylococcus carnosus (23), Lactobacillus plantarum (12), Lactobacillus brevis (10), Lactobacillus sakei (1), Weissella confusa (1), and Weissella cibaria (1). All strains were typed by RAPD-PCR, and their susceptibility to 15 antibiotics was determined and expressed as the minimum inhibitory concentration (MIC) using agar dilution method. High resistance to penicillin G, streptomycin, gentamycin, vancomycin, chloramphenicol, norfloxacin, ciprofloxacin, kanamycin, and neomycin was found among the isolates. All the strains were sensitive to ampicillin, while the susceptibility to tetracycline, oxytetracycline, erythromycin, lincomycin, and roxithromycin varied. The presence of relevant resistance genes was investigated by PCR and sequencing, with the following genes detected: str(A), str(B), tet(O), tet(M), ere(A), and catA. Eleven strains, including 3 S. carnosus, 6 L. plantarum, and 2 L. brevis, harbored more than 3 antibiotic resistance genes. Overall, multiple antibiotic resistance patterns were widely observed in LAB and S. carnosus strains isolated from Hunan smoked pork. Risk assessment should be carried out with regard to the safe use of LAB and CNS in food production. PRACTICAL APPLICATION: We evaluated the antibiotic resistance of lactic acid bacteria and coagulase-negative staphylococci strains isolated from Chinese naturally fermented smoked pork. Our results may provide important data on establishing breakpoint standards for LAB and CNS and evaluating the safety risk of these strains for commercial use.201829786847
348160.9722Antibiotics and Antibiotic Resistance Genes in Sediment of Honghu Lake and East Dongting Lake, China. Sediment is an ideal medium for the aggregation and dissemination of antibiotics and antibiotic resistance genes (ARGs). The levels of antibiotics and ARGs in Honghu Lake and East Dongting Lake of central China were investigated in this study. The concentrations of eight antibiotics (four sulfonamides and four tetracyclines) in Honghu Lake were in the range 90.00-437.43 μg kg(-1) (dry weight (dw)) with mean value of 278.21 μg kg(-1) dw, which was significantly higher than those in East Dongting Lake (60.02-321.04 μg kg(-1) dw, mean value of 195.70 μg kg(-1) dw). Among the tested three sulfonamide resistance genes (sul) and eight tetracycline resistance genes (tet), sul1, sul2, tetA, tetC, and tetM had 100 % detection frequency in sediment samples of East Dongting Lake, while only sul1, sul2, and tetC were observed in all samples of Honghu Lake. The relative abundance of sul2 was higher than that of sul1 at p < 0.05 level in both lakes. The relative abundance of tet genes in East Dongting Lake was in the following order: tetM > tetB > tetC > tetA. The relative abundance of sul1, sul2, and tetC in East Dongting Lake was significantly higher than those in Honghu Lake. The abundance of background bacteria may play an important role in the horizontal spread of sul2 and tetC genes in Honghu Lake and sul1 in East Dongting Lake, respectively. Redundancy analysis indicated that tetracyclines may play a more important role than sulfonamides in the abundance of sul1, sul2, and tetC gens in Honghu Lake and East Dongting Lake.201627418176
352670.9721The impact of antibiotic residues on resistance patterns in leek at harvest. When crops are cultivated on fields fertilized with animal manure, the risk exists that plants may take up antibiotic residues and may be exposed to antibiotic resistance genes and antibiotic resistant bacteria. During cultivation in a greenhouse pot experiment, leek (Allium porrum) was fertilized with either pig slurry or mineral fertilizer and exposed to either no antibiotics, doxycycline (10,000 μg/kg manure), sulfadiazine (1000 μg/kg manure), or lincomycin (1000 μg/kg manure). At harvest, 4.5 months later, lincomycin, sulfadiazine or doxycycline were not detected in any of the leek samples nor in their corresponding soil samples. Further, antimicrobial susceptibility testing was performed on 181 Bacillus cereus group isolates and 52 Pseudomonas aeruginosa isolates from the grown leek. For the B. cereus group isolates, only a small shift in MIC50 for lincomycin was observed among isolates from the lincomycin and control treatment. For P. aeruginosa, only in the setup with doxycycline treatment a higher MIC50 for doxycycline was observed compared to the control, specifically the isolates selected from growth media supplemented with 8 mg/L doxycycline. Nine antibiotic resistance genes (tet(B), tet(L), tet(M), tet(O), tet(Q), tet(W), erm(B), erm(F) and sul2) were investigated at harvest in the leek and soil samples. In the leek samples, none of the antibiotic resistance genes were detected. In the soil samples fertilized with pig slurry, the genes erm(B), erm(F), tet(M), sul2, tet(W) and tet(O) were detected in significantly higher copy numbers in the lincomycin treatment as compared to the other antibiotic treatments. This could be due to a shift in soil microbiota induced by the addition of lincomycin. The results of this study indicate that consumption of leek carries a low risk of exposure to antibiotic residues or antibiotic resistance to doxycycline, sulfadiazine or lincomycin.202337215782
526180.9720Prevalence of antibiotic resistance genes from effluent of coastal aquaculture, South Korea. The wide use of antibiotics in aquaculture for prophylactic and therapeutic purposes can potentially lead to the prevalence of antibiotic resistance genes (ARGs). This study reports for the first time the profile of ARGs from effluents of coastal aquaculture located in South Jeolla province and Jeju Island, South Korea. Using quantitative PCR (qPCR), twenty-two ARGs encoding tetracycline resistance (tetA, tetB, tetD, tetE, tetG, tetH, tetM, tetQ, tetX, tetZ, tetBP), sulfonamide resistance (sul1, sul2), quinolone resistance (qnrD, qnrS, aac(6')-Ib-cr), β-lactams resistance (bla(TEM), bla(CTX), bla(SHV)), macrolide resistance (ermC), florfenicol resistance (floR) and multidrug resistance (oqxA) and a class 1 integrons-integrase gene (intI1) were quantified. In addition, Illumina Miseq sequencing was applied to investigate microbial community differences across fish farm effluents. Results from qPCR showed that the total number of detected ARGs ranged from 4.24 × 10(-3) to 1.46 × 10(-2) copies/16S rRNA gene. Among them, tetB and tetD were predominant, accounting for 74.8%-98.0% of the total ARGs. Furthermore, intI1 gene showed positive correlation with tetB, tetD, tetE, tetH, tetX, tetZ tetQ and sul1. Microbial community analysis revealed potential host bacteria for ARGs and intI1. Two genera, Vibrio and Marinomonas belonging to Gammaproteobacteria, showed significant correlation with tetB and tetD, the most dominant ARGs in all samples. Also, operational taxonomic units (OTUs)-based network analysis revealed that ten OTUs, classified into the phyla Proteobacteria, Cyanobacteria/Chloroplast, Bacteroidetes, Verrucomicrobia and an unclassified phylum, were potential hosts of tetracycline resistance genes (i.e., tetA, tetG, tetH, tetM, tetQ and tetZ). Further systematic monitoring of ARGs is warranted for risk assessment and management of antibacterial resistance from fish farm effluents.201829031406
544590.9720Antibiotic resistance of Aeromonas ssp. strains isolated from Sparus aurata reared in Italian mariculture farms. Selective pressure in the aquatic environment of intensive fish farms leads to acquired antibiotic resistance. This study used the broth microdilution method to measure minimum inhibitory concentrations (MICs) of 15 antibiotics against 104 Aeromonas spp. strains randomly selected among bacteria isolated from Sparus aurata reared in six Italian mariculture farms. The antimicrobial agents chosen were representative of those primarily used in aquaculture and human therapy and included oxolinic acid (OXA), ampicillin (AM), amoxicillin (AMX), cephalothin (CF), cloramphenicol (CL), erythromycin (E), florfenicol (FF), flumequine (FM), gentamicin (GM), kanamycin (K), oxytetracycline (OT), streptomycin (S), sulfadiazine (SZ), tetracycline (TE) and trimethoprim (TMP). The most prevalent species selected from positive samples was Aeromonas media (15 strains). The bacterial strains showed high resistance to SZ, AMX, AM, E, CF, S and TMP antibiotics. Conversely, TE and CL showed MIC(90) values lower than breakpoints for susceptibility and many isolates were susceptible to OXA, GM, FF, FM, K and OT antibiotics. Almost all Aeromonas spp. strains showed multiple antibiotic resistance. Epidemiological cut-off values (ECVs) for Aeromonas spp. were based on the MIC distributions obtained. The results showed a high frequency of Aeromonas spp. contamination in Sparus aurata reared on the Italian coast and an elevated biodiversity in isolated bacterial strains. Aeromonas isolates comprise potentially pathogenic species for humans, often resistant to several antibiotics and able to transfer the genes responsible for antibiotic resistance to microorganisms pathogenic for humans throughout the food chain. The few ECV studies available on many antibiotics against Aeromonas spp. strains isolated from the aquaculture environment highlight the need for further research in this area, while regular monitoring programmes should be stepped up to check for antibiotic resistance.201830081345
5403100.9720Distribution of antimicrobial-resistant lactic acid bacteria in natural cheese in Japan. To determine and compare the extent of contamination caused by antimicrobial-resistant lactic acid bacteria (LAB) in imported and domestic natural cheeses on the Japanese market, LAB were isolated using deMan, Rogosa and Sharpe (MRS) agar and MRS agar supplemented with six antimicrobials. From 38 imported and 24 Japanese cheeses, 409 LAB isolates were obtained and their antimicrobial resistance was tested. The percentage of LAB resistant to dihydrostreptomycin, erythromycin, and/or oxytetracycline isolated from imported cheeses (42.1%) was significantly higher than that of LAB resistant to dihydrostreptomycin or oxytetracycline from cheeses produced in Japan (16.7%; P=0.04). Antimicrobial resistance genes were detected in Enterococcus faecalis (tetL, tetM, and ermB; tetL and ermB; tetM) E. faecium (tetM), Lactococcus lactis (tetS), Lactobacillus (Lb.), casei/paracasei (tetM or tetW), and Lb. rhamnosus (ermB) isolated from seven imported cheeses. Moreover, these E. faecalis isolates were able to transfer antimicrobial resistance gene(s). Although antimicrobial resistance genes were not detected in any LAB isolates from Japanese cheeses, Lb. casei/paracasei and Lb. coryniformis isolates from a Japanese farm-made cheese were resistant to oxytetracycline (minimal inhibitory concentration [MIC], 32 µg/mL). Leuconostoc isolates from three Japanese farm-made cheeses were also resistant to dihydrostreptomycin (MIC, 32 to >512 µg/mL). In conclusion, the present study demonstrated contamination with antimicrobial-resistant LAB in imported and Japanese farm-made cheeses on the Japanese market, but not in Japanese commercial cheeses.201323930694
7214110.9719Long-term application of fresh and composted manure increase tetracycline resistance in the arable soil of eastern China. The aim of this study was to compare the occurrence, abundance, and diversity of tetracycline resistance genes (tet) in agricultural soils after 6 years' application of fresh or composted swine manure. Soil samples were collected from fresh or composted manure-treated farmland at three depths (0-5 cm, 5-10 cm, and 10-20 cm). Nine classes of tet genes [tetW, tetB(P), tetO, tetS, tetC, tetG, tetZ, tetL, and tetX] were detected; tetG, tetZ, tetL, and tetB(P) were predominant in the manure-treated soil. The abundances of tetB(P), tetW, tetC, and tetO were reduced, while tetG and tetL were increased by fertilizing with composted versus fresh manure; thus, the total abundance of tet genes was not significantly reduced by compost manuring. tetG was the most abundant gene in manure-treated soil; the predominant tetG genotypes shared high homology with pathogenic bacteria. The tetG isolates were more diverse in soils treated with fresh versus composted manure, although the residual tet genes in composted manure remain a pollutant and produce a different influence on the tet gene resistome in field soil.201525460961
5396120.9719Antibiotic Resistance of Coagulase-Negative Staphylococci and Lactic Acid Bacteria Isolated from Naturally Fermented Chinese Cured Beef. This study provided phenotypic and molecular analysis of the antibiotic resistance within coagulase-negative staphylococci and lactic acid bacteria isolated from naturally fermented Chinese cured beef. A total of 49 strains were isolated by selective medium and identified at the species level by 16S rRNA gene sequencing as follows: Staphylococcus carnosus (37), Lactobacillus plantarum (6), Weissella confusa (4), Lactobacillus sakei (1), and Weissella cibaria (1). All strains were typed by random amplified polymorphic DNA fingerprinting, and their antibiotic resistances profiles to 15 antibiotics were determined as the MIC by using the agar dilution method. All the tested strains were sensitive to ampicillin, and most of them were also sensitive to penicillin, gentamycin, neomycin, norfloxacin, and ciprofloxacin with low MICs. High resistance to streptomycin, vancomycin, erythromycin, roxithromycin, lincomycin, and kanamycin was widely observed, while the resistant levels to tetracycline, oxytetracycline, and chloramphenicol varied. The presence of corresponding resistance genes in resistant isolates was investigated by PCR, with the following genes detected: tet(M) gene in 9 S. carnosus strains and 1 W. confusa strain; erm(F) gene in 10 S. carnosus strains; ere(A) gene in 6 S. carnosus strains; ere(A) gene in 4 S. carnosus strains and 1 L. plantarum strain; and str(A) gene and str(B) gene in 3 S. carnosus strains. The results indicated that multiple antibiotic resistances were common in coagulase-negative staphylococci and lactic acid bacteria strains isolated from naturally fermented Chinese cured beef. Safety analysis and risk assessment should be performed for application in meat products.201830485765
7757130.9718Removal of antibiotics and antibiotic resistance genes from domestic sewage by constructed wetlands: Effect of flow configuration and plant species. This study aims to investigate the removal of antibiotics and antibiotic resistance genes (ARGs) in raw domestic wastewater by various mesocosm-scale constructed wetlands (CWs) with different flow configurations or plant species including the constructed wetland with or without plant. Six mesocosm-scale CWs with three flow types (surface flow, horizontal subsurface flow and vertical subsurface flow) and two plant species (Thaliadealbata Fraser and Iris tectorum Maxim) were set up in the outdoor. 8 antibiotics including erythromycin-H2O (ETM-H2O), monensin (MON), clarithromycin (CTM), leucomycin (LCM), sulfamethoxazole (SMX), trimethoprim (TMP), sulfamethazine (SMZ) and sulfapyridine (SPD) and 12 genes including three sulfonamide resistance genes (sul1, sul2 and sul3), four tetracycline resistance genes (tetG, tetM, tetO and tetX), two macrolide resistance genes (ermB and ermC), two chloramphenicol resistance genes (cmlA and floR) and 16S rRNA (bacteria) were determined in different matrices (water, particle, substrate and plant phases) from the mesocosm-scale systems. The aqueous removal efficiencies of total antibiotics ranged from 75.8 to 98.6%, while those of total ARGs varied between 63.9 and 84.0% by the mesocosm-scale CWs. The presence of plants was beneficial to the removal of pollutants, and the subsurface flow CWs had higher pollutant removal than the surface flow CWs, especially for antibiotics. According to the mass balance analysis, the masses of all detected antibiotics during the operation period were 247,000, 4920-10,600, 0.05-0.41 and 3500-60,000μg in influent, substrate, plant and effluent of the mesocosm-scale CWs. In the CWs, biodegradation, substrate adsorption and plant uptake all played certain roles in reducing the loadings of nutrients, antibiotics and ARGs, but biodegradation was the most important process in the removal of these pollutants.201627443461
1379140.9718Antibiotic Resistance and Genetic Profiles of Vibrio parahaemolyticus Isolated from Farmed Pacific White Shrimp (Litopenaeus vannamei) in Ningde Regions. To better understand the antibiotic resistance, virulence genes, and some related drug-resistance genes of Vibrio parahaemolyticus in farmed pacific white shrimp (Litopenaeus vannamei) in Ningde regions, Fujian province, we collected and isolated a total of 102 strains of V. parahaemolyticus from farmed pacific white shrimp in three different areas of Ningde in 2022. The Kirby-Bauer disk method was used to detect V. parahaemolyticus resistance to 22 antibiotics, and resistant genes (such as quinolones (qnrVC136, qnrVC457, qnrA), tetracyclines (tet A, tetM, tetB), sulfonamides (sulI, sulII, sulIII), aminoglycosides (strA, strB), phenicols (cat, optrA, floR, cfr), β-lactams (carB), and macrolides (erm)) were detected by using PCR. The findings in this study revealed that V. parahaemolyticus was most resistant to sulfamoxazole, rifampicin, and erythromycin, with resistance rates of 56.9%, 36.3%, and 33.3%, respectively. Flufenicol, chloramphenicol, and ofloxacin susceptibility rates were 97.1%, 94.1%, and 92.2%, respectively. In all, 46% of the bacteria tested positive for multi-drug resistance. The virulence gene test revealed that all bacteria lacked the tdh and trh genes. Furthermore, 91.84% and 52.04% of the isolates were largely mediated by cat and sulII, respectively, with less than 5% resistance to aminoglycosides and macrolides. There was a clear mismatch between the antimicrobial resistance phenotypes and genotypes, indicating the complexities of V. parahaemolyticus resistance.202438257979
1329150.9717First report of the Staphylococcus aureus isolate from subclinical bovine mastitis in the South of Brazil harboring resistance gene dfrG and transposon family Tn916-1545. The aim of this work was to identify at the molecular level the species of coagulase-positive staphylococci isolates from clinical and subclinical bovine mastitis samples in Southern Brazil, and to evaluate the antimicrobial resistance profile, as well as the presence of resistance genes. According to the PCR assay, all 31 isolates were classified as Staphylococcus aureus. The isolates were tested for resistance to penicillin, ampicillin, oxacillin, cefoxitin, cephalothin, ceftiofur, streptomycin, tobramycin, teicoplanin, erythromycin, clindamycin, enrofloxacin, sulfonamide, trimethoprim-sulfamethoxazole, trimethoprim, and tetracycline by the disk diffusion method. Most of the isolates were resistant to sulfonamide (20), followed by ampicillin and clindamycin (16). Twenty isolates were multidrug-resistant. PCR was used for the detection of several antimicrobial resistance genes (ereB, ermB, ermC, tetA, tetB, tetK, tetL, tetM, tetO, Tn916-1545, strA, strB, sul1, sul2, dfrA, dfrG, dfrK, blaZ, mecA, and mecC). The most prevalent antimicrobial resistance genes were tetK and tetL, ereB, followed by tetM, Tn916-1545 and blaZ, detected in 11, nine and four isolates, respectively. For all the tetM gene positive isolates, the presence of conjugative transposons of the Tn916-1545 family was detected. The presence of multidrug-resistant isolates, antimicrobial resistance genes and transposons suggests a potential risk of spreading multi-resistance genes to other bacteria.201729051059
5392160.9717Characterization and transfer of antibiotic resistance in lactic acid bacteria from fermented food products. The study provides phenotypic and molecular analyses of the antibiotic resistance in lactic acid bacteria (LAB) from fermented foods in Xi'an, China. LAB strains (n = 84) belonging to 16 species of Lactobacillus (n = 73), and Streptococcus thermophilus (n = 11) were isolated and identified by sequencing their 16S rRNA gene. All strains were susceptible to ampicillin, bacitracin, and cefsulodin, and intrinsically resistant to nalidixic acid, kanamycin, and vancomycin (except L. bulgaricus, L. acidophilus, and S. thermophilus, which were susceptible to vancomycin). Some strains had acquired resistance for penicillin (n = 2), erythromycin (n = 9), clindamycin (n = 5), and tetracycline (n = 14), while resistance to gentamycin, ciprofloxacin, streptomycin, and chloramphenicol was species dependent. Minimum inhibitory concentrations presented in this study will help to review microbiological breakpoints for some of the species of Lactobacillus. The erm(B) gene was detected from two strains of each of L. fermentum and L. vaginalis, and one strain of each of L. plantarum, L. salivarius, L. acidophilus, L. animalis, and S. thermophilus. The tet genes were identified from 12 strains of lactobacilli from traditional foods. This is the first time, the authors identified tet(S) gene from L. brevis and L. kefiri. The erm(B) gene from L. fermentum NWL24 and L. salivarius NWL33, and tet(M) gene from L. plantarum NWL22 and L. brevis NWL59 were successfully transferred to Enterococcus faecalis 181 by filter mating. It was concluded that acquired antibiotic resistance is well dispersed in fermented food products in Xi'an, China and its transferability to other genera should be monitored closely.201121212956
7998170.9716Seasonal variation and removal efficiency of antibiotic resistance genes during wastewater treatment of swine farms. The seasonal variation and removal efficiency of antibiotic resistance genes (ARGs), including tetracycline resistance genes (tetG, tetM, and tetX) and macrolide (ermB, ermF, ereA, and mefA), were investigated in two typical swine wastewater treatment systems in both winter and summer. ARGs, class 1 integron gene, and 16S rRNA gene were quantified using real-time polymerase chain reaction assays. There was a 0.31-3.52 log variation in ARGs in raw swine wastewater, and the abundance of ARGs in winter was higher than in summer. tetM, tetX, ermB, ermF, and mefA were highly abundant. The abundance of ARGs was effectively reduced by most individual treatment process and the removal efficiencies of ARGs were higher in winter than in summer. However, when examining relative abundance, the fate of ARGs was quite variable. Anaerobic digestion reduced the relative abundance of tetX, ermB, ermF, and mefA, while lagoon treatment decreased tetM, ermB, ermF, and mefA. Sequencing batch reactor (SBR) decreased tetM, ermB, and ermF, but biofilters and wetlands did not display consistent removal efficiency on ARGs in two sampling seasons. As far as the entire treatment system is concerned, ermB and mefA were effectively reduced in both winter and summer in both total and relative abundance. The relative abundances of tetG and ereA were significantly correlated with intI1 (p < 0.01), and both tetG and ereA increased after wastewater treatment. This may pose a great threat to public health.201726715413
8029180.9716Migration of antibiotic resistance genes and evolution of flora structure in the Xenopus tropicalis intestinal tract with combined exposure to roxithromycin and oxytetracycline. The intestinal flora is one of the most important environments for antibiotic resistance development, owing to its diverse mix of bacteria. An excellent medicine model organism, Xenopus tropicalis, was selected to investigate the spread of antibiotic resistance genes (ARGs) in the intestinal bacterial community with single or combined exposure to roxithromycin (ROX) and oxytetracycline (OTC). Seventeen resistance genes (tetA, tetB, tetE, tetM, tetO, tetS, tetX, ermF, msrA, mefA, ereA, ereB, mphA, mphB, intI1, intI2, intI3) were detected in the intestines of Xenopus tropicalis living in three testing tanks (ROX tanks, OTC tanks, ROX + OTC tanks) and a blank tank for 20 days. The results showed that the relative abundance of total ARGs increased obviously in the tank with single stress but decreased in the tank with combined stress, and the genes encoding the macrolide antibiotic efflux pump (msrA), phosphatase (mphB) and integron (intI2, intI3) were the most sensitive. With the aid of AFM scanning, DNA was found to be scattered short chain in the blank, became extended or curled and then compacted with the stress from a single antibiotic, and was compacted and then fragmented with combined stress, which might be the reason for the variation of the abundance of ARGs with stress. The ratio of Firmicutes/Bacteroides related to diseases was increased by ROX and OTC. The very significant correlation between intI2 and intI3 with tetS (p ≤ 0.001) hinted at a high risk of ARG transmission in the intestines. Collectively, our results suggested that the relative abundance of intestinal ARGs could be changed depending on the intestinal microbiome and DNA structures upon exposure to antibiotics at environmental concentrations.202235063519
5390190.9715Presence of erythromycin and tetracycline resistance genes in lactic acid bacteria from fermented foods of Indian origin. Lactic acid bacteria (LAB) resistant to erythromycin were isolated from different food samples on selective media. The isolates were identified as Enterococcus durans, Enterococcus faecium, Enterococcus lactis, Enterococcus casseliflavus, Lactobacillus salivarius, Lactobacillus reuteri, Lactobacillus plantarum, Lactobacillus fermentum, Pediococcus pentosaceus and Leuconostoc mesenteroides. Of the total 60 isolates, 88 % harbored the ermB gene. The efflux gene msrA was identified in E. faecium, E. durans, E. lactis, E. casseliflavus, P. pentosaceus and L. fermentum. Further analysis of the msrA gene by sequencing suggested its homology to msrC. Resistance to tetracycline due to the genes tetM, tetW, tetO, tetK and tetL, alone or in combination, were identified in Lactobacillus species. The tetracycline efflux genes tetK and tetL occurred in P. pentosaceus and Enterococcus species. Since it appeared that LAB had acquired these genes, fermented foods may be a source of antibiotic resistance.201222644346