# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 2049 | 0 | 0.8859 | Genetic markers for detection of Escherichia coli K-12 harboring ampicillin-resistance plasmid from an industrial wastewater treatment effluent pond. Biotechnology industries that use recombinant DNA technology are potential sources for release of genetically modified organisms to the environment. Antibiotic-resistance marker genes are commonly used for recombinant bacteria selection. One example is the marker gene coding for β-lactamase (bla) in plasmids found in Escherichia coli K-12. The aim of this study was to provide an approach to develop a molecular method for genetic marker detection in E. coli K-12 harboring bla genes from an industrial wastewater treatment effluent pond (IWTEP). For the detection of bla and Achromobacter lyticus protease I (api) genes in samples from IWTEP, we employed multiplex polymerase chain reaction (PCR) using E. coli K-12 genetic marker detection primers, previously described in the literature, and primers designed in our laboratory. The microbiological screening method resulted in 22 bacterial colony-forming units isolated from three different IWTEP harvesting points. The multiplex PCR amplicons showed that five isolates were positive for the bla gene marker and negative for the E. coli K-12 and api genes. The 16S rRNA regions of positive microorganisms carrying the bla gene were genotyped by the MicroSeq®500 system. The bacteria found were Escherichia spp (3/5), Chromobacterium spp (1/5), and Aeromonas spp (1/5). None of the 22 isolated microorganisms presented the molecular pattern of E. coli K-12 harboring the bla gene. The presence of microorganisms positive for the bla gene and negative for E. coli K-12 harboring bla genes at IWTEP suggests that the ampicillin resistance found in the isolated bacteria could be from microorganisms other than the E. coli K-12 strain harboring plasmid. | 2016 | 27323199 |
| 5220 | 1 | 0.8853 | The first report of the vanC₁ gene in Enterococcus faecium isolated from a human clinical specimen. The vanC₁ gene, which is chromosomally located, confers resistance to vancomycin and serves as a species marker for Enterococcus gallinarum. Enterococcus faecium TJ4031 was isolated from a blood culture and harbours the vanC₁gene. Polymerase chain reaction (PCR) assays were performed to detect vanXYc and vanTc genes. Only the vanXYc gene was found in the E. faecium TJ4031 isolate. The minimum inhibitory concentrations of vancomycin and teicoplanin were 2 µg/mL and 1 µg/mL, respectively. Real-time reverse transcription-PCR results revealed that the vanC₁ and vanXYc genes were not expressed. Pulsed-field gel electrophoresis and southern hybridisation results showed that the vanC₁ gene was encoded in the chromosome. E. faecalis isolated from animals has been reported to harbour vanC₁gene. However, this study is the first to report the presence of the vanC₁gene in E. faecium of human origin. Additionally, our research showed the vanC₁gene cannot serve as a species-specific gene of E. gallinarum and that it is able to be transferred between bacteria. Although the resistance marker is not expressed in the strain, our results showed that E. faecium could acquire the vanC₁gene from different species. | 2014 | 25317698 |
| 1244 | 2 | 0.8845 | Identification of antibiotic resistance genes in Escherichia coli from subclinical mastitis milk in dairy cows and goats, East Java Province. Antibiotics are still used to treat mastitis in dairy cows in Indonesia. This study aimed to analyse antibiotic resistance genes in Escherichia coli (E. coli) from subclinical mastitis milk in East Java Province, Indonesia. The samples consisted of subclinical mastitis milk from cows and goats. A total of 592-quarter cow's milk and 71 goat's milk samples from both halves of the udder were collected from 67 farms in Lumajang, Banyuwangi, Malang, Sidoarjo, Jember, Pasuruan, Probolinggo, and Mojokerto. Subclinical mastitis samples were screened using the California mastitis test (CMT). E. coli was identified by phenotypic and genotypic methods. E. coli was confirmed with a primer specific to the polymerase chain reaction (PCR) technique. Gene resistance of E. coli was tested using the multiplex-PCR (mPCR) technique with primers encoding the genes temoneira enzyme (TEM), oxacillinase (OXA), sulfhydryl variable (SHV), and cefotaximase-munich IV (CTX-M IV). These genes were chosen because mastitis treatment generally uses oxacilline and β-lactam antibiotics. All data obtained were analysed descriptively. The results show that six isolates of E. coli (46.15%) carried a single resistance gene (TEM or SHV) and two isolates (33.33%) were confirmed as multiple drug-resistant organisms (MDROs) (TEM and SHV). The resistance genes were found in samples originating from Blitar, Banyuwangi, Lumajang, and Pasuruan Regencies. This research implies that antibiotic-resistance genes found in E. coli on certain farms are dangerous and may allow gene transmission to other bacteria that make treatment for mastitis or other bacterial infections ineffective. | 2024 | 38550619 |
| 5219 | 3 | 0.8843 | The first report of the vanC1 gene in Enterococcus faecium isolated from a human clinical specimen. The vanC1 gene, which is chromosomally located, confers resistance to vancomycin and serves as a species marker for Enterococcus gallinarum. Enterococcus faecium TJ4031 was isolated from a blood culture and harbours the vanC1gene. Polymerase chain reaction (PCR) assays were performed to detect vanXYc and vanTc genes. Only the vanXYc gene was found in the E. faecium TJ4031 isolate. The minimum inhibitory concentrations of vancomycin and teicoplanin were 2 µg/mL and 1 µg/mL, respectively. Real-time reverse transcription-PCR results revealed that the vanC1and vanXYc genes were not expressed. Pulsed-field gel electrophoresis and southern hybridisation results showed that the vanC1 gene was encoded in the chromosome. E. faecalis isolated from animals has been reported to harbour vanC1gene. However, this study is the first to report the presence of the vanC1gene in E. faecium of human origin. Additionally, our research showed the vanC1gene cannot serve as a species-specific gene of E. gallinarum and that it is able to be transferred between bacteria. Although the resistance marker is not expressed in the strain, our results showed that E. faecium could acquire the vanC1gene from different species. | 2014 | 25119395 |
| 9999 | 4 | 0.8841 | Assessment of competitiveness of rhizobia infecting Galega orientalis on the basis of plant yield, nodulation, and strain identification by antibiotic resistance and PCR. Competition between effective and ineffective Rhizobium galegae strains nodulating Galega orientalis was examined on the basis of plant growth, nodulation, antibiotic resistance, and PCR results. In a preliminary experiment in Leonard's jars, ineffective R. galegae strains HAMBI 1207 and HAMBI 1209 competed in similar manners with the effective strain R. galegae HAMBI 1174. In a pot experiment, soil was inoculated with 0 to 10(5) HAMBI 1207 cells per g before G. orientalis was sown. Seeds of G. orientalis were surface inoculated with 2 x 10(4) and 2 x 10(5) cells of HAMBI 1174 per seed (which represent half and fivefold the commercially recommended amount of inoculant, respectively). Plant yield and nodulation by the effective strain were significantly reduced, with as few as 10(2) ineffective rhizobia per g of soil, and the inoculation response was not improved by the 10-fold greater dose of the inoculant. Bacteria occupying the nodules were identified by antibiotic resistance and PCR with primers specific for R. galegae HAMBI 1174, R. galegae, and genes coding for bacterial 16S rRNA (bacterial 16S rDNA). Sixty-two large nodules examined were occupied by the effective strain HAMBI 1174, as proven by antibiotic resistance and amplification of the strain-specific fragment. From 20 small nodules, only the species-specific fragment could be amplified, and isolated bacteria had the same antibiotic resistance and 16S PCR restriction pattern as strain HAMBI 1207. PCR with our strain-specific and species-specific primers provides a powerful tool for strain identification of R. galegae directly from nodules without genetic modification of the bacteria. | 1996 | 8593053 |
| 531 | 5 | 0.8839 | p-Aminobenzoic acid and chloramphenicol biosynthesis in Streptomyces venezuelae: gene sets for a key enzyme, 4-amino-4-deoxychorismate synthase. Amplification of sequences from Streptomyces venezuelae ISP5230 genomic DNA using PCR with primers based on conserved prokaryotic pabB sequences gave two main products. One matched pabAB, a locus previously identified in S. venezuelae. The second closely resembled the conserved pabB sequence consensus and hybridized with a 3.8 kb NcoI fragment of S. venezuelae ISP5230 genomic DNA. Cloning and sequence analysis of the 3.8 kb fragment detected three ORFs, and their deduced amino acid sequences were used in BLAST searches of the GenBank database. The ORF1 product was similar to PabB in other bacteria and to the PabB domain encoded by S. venezuelae pabAB. The ORF2 product resembled PabA of other bacteria. ORF3 was incomplete; its deduced partial amino acid sequence placed it in the MocR group of GntR-type transcriptional regulators. Introducing vectors containing the 3.8 kb NcoI fragment of S. venezuelae DNA into pabA and pabB mutants of Escherichia coli, or into the Streptomyces lividans pab mutant JG10, enhanced sulfanilamide resistance in the host strains. The increased resistance was attributed to expression of the pair of discrete translationally coupled p-aminobenzoic acid biosynthesis genes (designated pabB/pabA) cloned in the 3.8 kb fragment. These represent a second set of genes encoding 4-amino-4-deoxychorismate synthase in S. venezuelae ISP5230. In contrast to the fused pabAB set previously isolated from this species, they do not participate in chloramphenicol biosynthesis, but like pabAB they can be disrupted without affecting growth on minimal medium. The gene disruption results suggest that S. venezuelae may have a third set of genes encoding PABA synthase. | 2001 | 11495989 |
| 2214 | 6 | 0.8838 | Development of multiplex recombinase polymerase amplification for the rapid detection of five carbapenemase (bla(KPC), bla(NDM), bla(OXA-48)-like, bla(IMP), and bla(VIM)) and 10 mcr (mcr-1 to mcr-10) genes in blood cultures. The emergence of plasmid-encoded carbapenemase and mobile colistin resistance (mcr) genes poses a significant challenge in controlling the spread of multidrug-resistant Gram-negative bacteria. Addressing this issue requires the development of rapid, accurate, and cost-effective tools for gene detection. For the first time, this study reports three multiplex recombinase polymerase amplification (RPA) assays, each designed to detect five resistance genes: carbapenemase (bla(KPC), bla(NDM), bla(OXA-48)-like, bla(IMP), and bla(VIM)), mcr-1 to mcr-5, and mcr-6 to mcr-10. Using agarose gel electrophoresis, all 15 target genes were successfully amplified by the three assays, demonstrating the potential of these assays for integration with rapid reporting platforms. To increase their applicability, the assays were combined with SYBR(Ⓡ) Green I for visual identification of all 15 target genes and with lateral flow immunoassays (LFIAs) for detection of two carbapenemase (bla(NDM) and bla(OXA-48)-like) and two mcr genes (mcr-1 and mcr-3) genes. Specificity testing showed that RPA-SYBR(Ⓡ) Green I and RPA-LFIAs produced no cross-reactivity among the target genes. The limit of detection for RPA-SYBR(Ⓡ) Green I, for all genes, ranged from 2 × 10(0) to 2 × 10(2) CFU/reaction, and for RPA-LFIAs from 2 × 10(0) to 2 × 10(3) CFU/reaction. The developed RPA-SYBR(Ⓡ) Green I and RPA-LFIAs successfully detected 15 and four target genes, from positive haemoculture bottles. These assays offer a promising approach for point-of-care testing. Providing a valuable tool for antimicrobial resistance surveillance and timely guidance for effective antibiotic intervention. | 2025 | 40618792 |
| 356 | 7 | 0.8837 | Development of an extrachromosomal cloning vector system for use in Borrelia burgdorferi. Molecular genetic analysis of Borrelia burgdorferi, the cause of Lyme disease, has been hampered by the absence of any means of efficient generation, identification, and complementation of chromosomal and plasmid null gene mutants. The similarity of borrelial G + C content to that of Gram-positive organisms suggested that a wide-host-range plasmid active in Gram-positive bacteria might also be recognized by borrelial DNA replication machinery. One such plasmid, pGK12, is able to propagate in both Gram-positive and Gram-negative bacteria and carries erythromycin and chloramphenicol resistance markers. pGK12 propagated extrachromosomally in B. burgdorferi B31 after electroporation but conferred only erythromycin resistance. pGK12 was used to express enhanced green fluorescent protein in B31 under the control of the flaB promoter. Escherichia coli transformed with pGK12 DNA extracted from B31 expressing only erythromycin resistance developed both erythromycin and chloramphenicol resistance, and plasmid DNA isolated from these transformed E. coli had a restriction pattern similar to the original pGK12. Our data indicate that the replicons of pGK12 can provide the basis to continue developing efficient genetic systems for B. burgdorferi together with the erythromycin resistance and reporter egfp genes. | 2000 | 10781091 |
| 1214 | 8 | 0.8837 | Plasmid-mediated quinolone resistance genes in fecal bacteria from rooks commonly wintering throughout Europe. This study concerned the occurrence of fecal bacteria with plasmid-mediated quinolone resistance (PMQR) genes in rooks (Corvus frugilegus, medium-sized corvid birds) wintering in continental Europe during winter 2010/2011. Samples of fresh rook feces were taken by cotton swabs at nine roosting places in eight European countries. Samples were transported to one laboratory and placed in buffered peptone water (BPW). The samples from BPW were enriched and subcultivated onto MacConkey agar (MCA) supplemented with ciprofloxacin (0.06 mg/L) to isolate fluoroquinolone-resistant bacteria. DNA was isolated from smears of bacterial colonies growing on MCA and tested by PCR for PMQR genes aac(6')-Ib, qepA, qnrA, qnrB, qnrC, qnrD, qnrS, and oqxAB. All the PCR products were further analyzed by sequencing. Ciprofloxacin-resistant bacteria were isolated from 37% (392 positive/1,073 examined) of samples. Frequencies of samples with ciprofloxacin-resistant isolates ranged significantly from 3% to 92% in different countries. The qnrS1 gene was found in 154 samples and qnrS2 in 2 samples. The gene aac(6')-Ib-cr was found in 16 samples. Thirteen samples were positive for qnrB genes in variants qnrB6 (one sample), qnrB18 (one), qnrB19 (one), qnrB29 (one), and qnrB49 (new variant) (one). Both the qnrD and oqxAB genes were detected in six samples. The genes qnrA, qnrC, and qepA were not found. Wintering omnivorous rooks in Europe were commonly colonized by bacteria supposedly Enterobacteriaceae with PMQR genes. Rooks may disseminate these epidemiologically important bacteria over long distances and pose a risk for environmental contamination. | 2012 | 22731858 |
| 396 | 9 | 0.8837 | A novel, highly efficient gene-cloning system in Micromonospora applied to the genetic analysis of fortimicin biosynthesis. We have developed a gene-cloning system in Micromonospora olivasterospora, a fortimicin A (astromicin) producer. Plasmids of Micromonospora from two strains of M. olivasterospora were used for construction of the vectors. Two antibiotic-resistance genes, nmrA and nmrB, cloned from a neomycin-producing Micromonospora, were introduced into these plasmids for the selection of transformants. In a new protoplasting protocol for lysozyme-resistant bacteria, protoplasts of M. olivasterospora were found in short-time incubation with lysozyme and transformed efficiently, indicating that the method was suitable to shotgun cloning. Using this system, seven biosynthetic genes for fortimicin A were cloned. Their physical maps revealed that at least four of these genes were clustered. Analysis of a cosmid library of M. olivasterospora showed that eleven biosynthetic genes and a self-defense gene existed in a region of approx. 25 kb of DNA. | 1992 | 1612453 |
| 1217 | 10 | 0.8835 | Antimicrobial Susceptibility Profiles among Pseudomonas aeruginosa Isolated from Professional SCUBA Divers with Otitis Externa, Swimming Pools and the Ocean at a Diving Operation in South Africa. SCUBA divers are predisposed to otitis externa caused by Pseudomonas aeruginosa, which is becoming increasingly multi-drug resistant (MDR). The present work assessed the antibiotic resistance profiles of P. aeruginosa obtained from SCUBA divers and their environment in Sodwana Bay, South Africa. Bacterial isolates from a total of 137 random water and ear swab samples were identified using biochemical and molecular methods. P. aeruginosa strains were further evaluated for antibiotic susceptibility using the Kirby-Bauer assay. Double disk synergy test (DDST) to confirm metallo-β-lactamase (MBL) production and PCR amplification of specific antibiotic resistance genes was performed. All (100%) 22 P. aeruginosa isolates recovered were resistant to 6 of the β-lactams tested including imipenem but exhibited susceptibility to trimethoprim-sulfamethoxazole. MBL production was observed in 77% of isolates while the most prevalent extended-spectrum β-lactamase (ESBL) genes present included bla(AmpC) (86.9%) followed by bla(TEM) (82.6%). Sulfonamide resistance was largely encoded by sul1 (63.6%) and sul2 (77.3%) genes with a high abundance of class 1 integrons (77.3%) of which 18.2% carried both Intl1 and Intl2. P. aeruginosa found in Sodwana Bay exhibits multi-drug resistance (MDRce) to several pharmaceutically important drugs with the potential to transfer antibiotic resistance to other bacteria if the judicious use of antibiotics for their treatment is not practiced. | 2022 | 35056039 |
| 2985 | 11 | 0.8831 | Development and evaluation of a Luminex xTAG assay for sulfonamide resistance genes in Escherichia coli and Salmonella isolates. Clinically occurring sulfonamide resistance in gram-negative bacteria is codified by several sul genes, mostly associated with the mobilized genetic elements named integrons, and integrons are frequently found in plasmids. There are four sul genes (sul1, sul2, sul3 and sul4) that encode resistance to sulfonamides. The aim of the present study was to develop a bead-based xTAG assay for the simultaneous detection of all four sul genes and related Class 1 integrons (int1) in Escherichia coli and Salmonella isolates. The limits of detection ranged from 10 to 1000 copies/μL of input purified plasmid DNA. Forty-one bacterial isolates from clinical samples were examined using the newly developed xTAG assay and also by conventional PCR to determine the relative performance of each. The results obtained by xTAG assay showed higher detection rates and accuracy for sul genes than conventional PCR. It indicated that the xTAG-multiplex PCR is a convenient method for rapid identification of sul genes. | 2020 | 31678631 |
| 5038 | 12 | 0.8830 | Simple and quick detection of extended-spectrum β-lactamase and carbapenemase-encoding genes using isothermal nucleic acid amplification techniques. The spread of plasmid-mediated antibiotic-resistant bacteria must be controlled; to this end, developing kits for simple and rapid detection in food and clinical settings is desirable. This review describes the detection of antibiotic resistance genes in extended-spectrum β-lactamase （ESBL）- and carbapenemase-producing bacteria. Loop-mediated isothermal amplification （LAMP）, a technique developed in Japan, is a useful diffusion amplification method that does not require equipment like thermal cyclers, and amplifies the target gene in 30 min at about 65℃. Although most reports targeting ESBL and carbapenemase genes are intended for clinical use, environmental and food samples have also been targeted. Recombinase polymerase amplification （RPA） has recently been developed; in RPA, the reaction proceeds under the human skin with reaction conditions of 30 min at 37℃. Detection of ESBL and carbapenemase-encoding genes in food and clinical samples using RPA has been reported in limited studies. However, research on RPA has just begun, and further development is expected. | 2023 | 38233166 |
| 1176 | 13 | 0.8829 | High carriage of plasmid-mediated quinolone resistance (PMQR) genes by ESBL-producing and fluoroquinolone-resistant Escherichia coli recovered from animal waste dumps. BACKGROUND: There has been a rise in the consumption of fluoroquinolones in human and veterinary medicine recently. This has contributed to the rising incidence of quinolone resistance in bacteria. This study aimed at the determination of the antibiotic resistance profile of ESBL-producing and fluoroquinolone-resistant E. coli (FQEC) isolated from animal waste obtained from the waste dumps of an agricultural farm and their carriage of genes encoding PMQR. METHODS AND RESULTS: Isolation of ESBL-producing E. coli from animal waste samples was done on CHROMagar ESBL, while presumptive isolates were purified, and identified via the detection of uidA gene. Susceptibility to a panel of ten antibiotics was done using the disc diffusion method, and detection of PMQR genes (qnrA, qnrB, qnrS, aac(6')-lb-cr, qepA and oqxAB) was done using monoplex and duplex PCR. Twenty-five ESBL-producing and FQEC were obtained from the cattle (6), piggery (7) and poultry (12) waste dumps of the farm. There was 100% resistance to cefpodoxime, cefotaxime, enrofloxacin, trimethoprim-sulfamethoxazole and penicillin by the isolates. The resistance to the other antibiotics was streptomycin (48%), ceftazidime (24%), while no isolate resisted amoxicillin-clavulanate and imipenem. The frequencies of PMQR genes detected were; qnrA (96%), oqxAB (96%), qnrB (92%), while qnrS was detected in 88% (22) of the isolates. Aminoglycoside acetyltransferase (aac(6')-lb-cr) and quinolone efflux pump (qepA) were each detected in 20 (80%) of the isolates. CONCLUSIONS: This study showed that animal wastes disposed indiscriminately into dumps could be a budding 'hotspot' for multidrug resistant, ESBL-producing and fluoroquinolone-resistant E. coli carrying multiple genes encoding resistance to fluoroquinolone antibiotics. | 2024 | 38491992 |
| 5086 | 14 | 0.8829 | Detection of genetically modified microorganisms in soil using the most-probable-number method with multiplex PCR and DNA dot blot. The principal objective of this study was to detect genetically modified microorganisms (GMMs) that might be accidentally released into the environment from laboratories. Two methods [plate counting and most-probable-number (MPN)] coupled with either multiplex PCR or DNA dot blots were compared using genetically modified Escherichia coli, Pseudomonas putida, and Acinetobacter oleivorans harboring an antibiotic-resistance gene with additional gfp and lacZ genes as markers. Alignments of sequences collected from databases using the Perl scripting language (Perl API) and from denaturing gradient gel electrophoresis analysis revealed that the gfp, lacZ and antibiotic-resistance genes (kanamycin, tetracycline, and ampicillin) in GMMs differed from the counterpart genes in many sequenced genomes and in soil DNA. Thus, specific multiplex PCR primer sets for detection of plasmid-based gfp and lacZ antibiotic-resistance genes could be generated. In the plate counting method, many antibiotic-resistant bacteria from a soil microcosm grew as colonies on antibiotic-containing agar plates. The multiplex PCR verification of randomly selected antibiotic-resistant colonies with specific primers proved ineffective. The MPN-multiplex PCR method and antibiotic-resistant phenotype could be successfully used to detect GMMs, although this method is quite laborious. The MPN-DNA dot blot method screened more cells at a time in a microtiter plate containing the corresponding antibiotics, and was shown to be a more efficient method for the detection of GMMs in soil using specific probes in terms of labor and accuracy. | 2011 | 21810467 |
| 521 | 15 | 0.8829 | Terbinafine resistance mediated by salicylate 1-monooxygenase in Aspergillus nidulans. Resistance to antifungal agents is a recurring and growing problem among patients with systemic fungal infections. UV-induced Aspergillus nidulans mutants resistant to terbinafine have been identified, and we report here the characterization of one such gene. A sib-selected, 6.6-kb genomic DNA fragment encodes a salicylate 1-monooxygenase (salA), and a fatty acid synthase subunit (fasC) confers terbinafine resistance upon transformation of a sensitive strain. Subfragments carrying salA but not fasC confer terbinafine resistance. salA is present as a single-copy gene on chromosome VI and encodes a protein of 473 amino acids that is homologous to salicylate 1-monooxygenase, a well-characterized naphthalene-degrading enzyme in bacteria. salA transcript accumulation analysis showed terbinafine-dependent induction in the wild type and the UV-induced mutant Terb7, as well as overexpression in a strain containing the salA subgenomic DNA fragment, probably due to the multicopy effect caused by the transformation event. Additional naphthalene degradation enzyme-coding genes are present in fungal genomes, suggesting that resistance could follow degradation of the naphthalene ring contained in terbinafine. | 2004 | 15328121 |
| 3619 | 16 | 0.8828 | Incidence of class 1 integrons in a quaternary ammonium compound-polluted environment. Samples of effluent and soil were collected from a reed bed system used to remediate liquid waste from a wool finishing mill with a high use of quaternary ammonium compounds (QACs) and were compared with samples of agricultural soils. Resistance quotients of aerobic gram-negative and gram-positive bacteria to ditallowdimethylammomium chloride (DTDMAC) and cetyltrimethylammonium bromide (CTAB) were established by plating onto nutrient agar containing 5 microg/ml or 50 microg/ml DTDMAC or CTAB. Approximately 500 isolates were obtained and screened for the presence of the intI1 (class 1 integrase), qacE (multidrug efflux), and qacE Delta1 (attenuated qacE) genes. QAC resistance was higher in isolates from reed bed samples, and class 1 integron incidence was significantly higher for populations that were preexposed to QACs. This is the first study to demonstrate that QAC selection in the natural environment has the potential to coselect for antibiotic resistance, as class 1 integrons are well-established vectors for cassette genes encoding antibiotic resistance. | 2005 | 15855499 |
| 7829 | 17 | 0.8828 | Insights into capture-inactivation/oxidation of antibiotic resistance bacteria and cell-free antibiotic resistance genes from waters using flexibly-functionalized microbubbles. The spread of antibiotic resistance in the aquatic environment severely threatens the public health and ecological security. This study investigated simultaneously capturing and inactivating/oxidizing the antibiotic resistant bacteria (ARB) and cell-free antibiotic resistance genes (ARGs) in waters by flexibly-functionalized microbubbles. The microbubbles were obtained by surface-modifying the bubbles with coagulant (named as coagulative colloidal gas aphrons, CCGAs) and further encapsulating ozone in the gas core (named as coagulative colloidal ozone aphrons, CCOAs). CCGAs removed 92.4-97.5% of the sulfamethoxazole-resistant bacteria in the presence of dissolved organic matter (DOM), and the log reduction of cell-free ARGs (particularly, those encoded in plasmid) reached 1.86-3.30. The ozone release from CCOAs led to efficient in-situ oxidation: 91.2% of ARB were membrane-damaged and inactivated. In the municipal wastewater matrix, the removal of ARB increased whilst that of cell-free ARGs decreased by CCGAs with the DOM content increasing. The ozone encapsulation into CCGAs reinforced the bubble performance. The predominant capture mechanism should be electrostatic attraction between bubbles and ARB (or cell-free ARGs), and DOM enhanced the sweeping and bridging effect. The functionalized microbubble technology can be a promising and effective barrier for ARB and cell-free ARGs with shortened retention time, lessened chemical doses and simplified treatment unit. | 2022 | 35063836 |
| 2995 | 18 | 0.8826 | Antibiotic resistance in bacteria from magpies (Pica pica) and rabbits (Oryctolagus cuniculus) from west Wales. The prevalence of antibiotic-resistant bacteria in wild animal and bird populations is largely unknown, with little consistency among the few published reports. We therefore examined intestinal bacteria from magpies (Pica pica) and rabbits (Oryctolagus cuniculus) collected in rural west Wales. Escherichia coli isolates resistant to multiple antibiotics were grown from eight of 20 magpies trapped in spring, 1999 and one of 17 in spring, 2000; the most prevalent resistance trait among these isolates was to tetracycline, but resistances to ampicillin, chloramphenicol, kanamycin, sulphonamide, tetracycline and trimethoprim were also found. Tetracycline-resistant Enterococcus spp. were found in one of 20 magpies in 1999 and three of 17 in 2000. Only one resistant E. coli isolate was detected among gut bacteria from 13 rabbits, and this strain was resistant only to tetracycline. Differences in the prevalence of resistance between bacteria from rabbits and magpies may reflect differences in diet: rabbits graze field edges, whereas magpies are omnivorous and opportunistic. The resistance genes found in E. coli isolates from magpies mostly corresponded to those common among human isolates, but those conferring tetracycline resistance were unique. | 2001 | 11722546 |
| 355 | 19 | 0.8824 | Evolution of multiple-antibiotic-resistance plasmids mediated by transposable plasmid deoxyribonucleic acid sequences. Two plasmid deoxyribonucleic acid sequences mediating multiple antibiotic resistance transposed in vivo between coexisting plasmids in clinical isolates of Serratia marcescens. This event resulted in the evolution of a transferable multiresistance plasmid. Both sequences, designated in Tn1699 and Tn1700, were flanked by inverted deoxyribonucleic acid repetitions and could transpose between replicons independently of the Excherichia coli recA gene function. Tn1699 and Tn1700 mediated ampicillin, carbenicillin, kanamycin, and gentamicin resistance but differed in the type of gentamicin-acetyltransferase enzymes that they encoded. The structural genes for these enzymes share a great deal of polynucleotide sequence similarity despite their phenotypic differences. The transposition of Tn1699 and Tn1700 to coresident transferable plasmids has contributed to the dissemination of antibiotic resistance among other gram-negative bacteria. These organisms have recently caused nosocomial infections in epidemic proportions. | 1979 | 387747 |