# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 3578 | 0 | 1.0000 | Analysis of newly detected tetracycline resistance genes and their flanking sequences in human intestinal bifidobacteria. Due to tetracycline abuse, the safe bifidobacteria in the human gastrointestinal intestinal tract (GIT) may serve as a reservoir of tetracycline resistance genes. In the present investigation of 92 bifidobacterial strains originating from the human GIT, tetracycline resistance in 29 strains was mediated by the tet(W), tet(O) or tet(S) gene, and this is the first report of tet(O)- and tet(S)-mediated tetracycline resistance in bifidobacteria. Antibiotic resistance genes harbored by bifidobacteria are transferred from other bacteria. However, the characteristics of the spread and integration of tetracycline resistance genes into the human intestinal bifidobacteria chromosome are poorly understood. Here, conserved sequences were identified in bifidobacterial strains positive for tet(W), tet(O), or tet(S), including the tet(W), tet(O), or tet(S) and their partial flanking sequences, which exhibited identity with the sequences in multiple human intestinal pathogens, and genes encoding 23 S rRNA, an ATP transporter, a Cpp protein, and a membrane-spanning protein were flanking by the 1920-bp tet(W), 1920-bp tet(O), 1800-bp tet(O) and 252-bp tet(S) in bifidobacteria, respectively. These findings suggest that tetracycline resistance genes harbored by human intestinal bifidobacteria might initially be transferred from pathogens and that each kind of tetracycline resistance gene might tend to insert in the vicinity of specific bifidobacteria genes. | 2017 | 28740169 |
| 3579 | 1 | 0.9998 | The Tetracycline Resistance Gene, tet(W) in Bifidobacterium animalis subsp. lactis Follows Phylogeny and Differs From tet(W) in Other Species. The tetracycline resistance gene tet(W) encodes a ribosomal protection protein that confers a low level of tetracycline resistance in the probiotic bacterium Bifidobacterium animalis subsp. lactis. With the aim of assessing its phylogenetic origin and potential mobility, we have performed phylogenetic and in silico genome analysis of tet(W) and its flanking genes. tet(W) was found in 41 out of 44 examined B. animalis subsp. lactis strains. In 38 strains, tet(W) was flanked by an IS5-like element and an open reading frame encoding a hypothetical protein, which exhibited a similar GC content (51-53%). These genes were positioned in the same genomic context within the examined genomes. Phylogenetically, the B. animalis subsp. lactis tet(W) cluster in a clade separate from tet(W) of other species and genera. This is not the case for tet(W) encoded by other bifidobacteria and other species where tet(W) is often found in association with transferable elements or in different genomic regions. An IS5-like element identical to the one flanking the B. animalis subsp. lactis tet(W) has been found in a human gut related bacterium, but it was not associated with any tet(W) genes. This suggests that the IS5-like element is not associated with genetic mobility. tet(W) and the IS5 element have previously been shown to be co-transcribed, indicating that co-localization may be associated with tet(W) expression. Here, we present a method where phylogenetic and in silico genome analysis can be used to determine whether antibiotic resistance genes should be considered innate (intrinsic) or acquired. We find that B. animalis subsp. lactis encoded tet(W) is part of the ancient resistome and thereby possess a negligible risk of transfer. | 2021 | 34335493 |
| 3595 | 2 | 0.9998 | Antibiotic Susceptibility, Resistance Gene Determinants and Corresponding Genomic Regions in Lactobacillus amylovorus Isolates Derived from Wild Boars and Domestic Pigs. Restrictions on the use of antibiotics in pigs lead to the continuous search for new probiotics serving as an alternative to antibiotics. One of the key parameters for probiotic bacteria selection is the absence of horizontally transmissible resistance genes. The aim of our study was to determine antibiotic susceptibility profiles in 28 Lactobacillus amylovorus isolates derived from the digestive tract of wild boars and farm pigs by means of the broth microdilution method and whole genome sequencing (WGS). We revealed genetic resistance determinants and examined sequences flanking resistance genes in these strains. Our findings indicate that L. amylovorus strains from domestic pigs are predominantly resistant to tetracycline, erythromycin and ampicillin. WGS analysis of horizontally transmissible genes revealed only three genetic determinants (tetW, ermB and aadE) of which all tetW and ermB genes were present only in strains derived from domestic pigs. Sequence analysis of coding sequences (CDS) in the neighborhood of the tetW gene revealed the presence of site-specific recombinase (xerC/D), site-specific DNA recombinase (spoIVCA) or DNA-binding transcriptional regulator (xre), usually directly downstream of the tetW gene. In the case of ermB, CDS for omega transcriptional repressor or mobilization protein were detected upstream of the ermB gene. | 2022 | 36677394 |
| 3594 | 3 | 0.9998 | Directed Recovery and Molecular Characterization of Antibiotic Resistance Plasmids from Cheese Bacteria. Resistance to antimicrobials is a growing problem of worldwide concern. Plasmids are thought to be major drivers of antibiotic resistance spread. The present work reports a simple way to recover replicative plasmids conferring antibiotic resistance from the bacteria in cheese. Purified plasmid DNA from colonies grown in the presence of tetracycline and erythromycin was introduced into plasmid-free strains of Lactococcus lactis, Lactiplantibacillus plantarum and Lacticaseibacillus casei. Following antibiotic selection, the plasmids from resistant transformants were isolated, analyzed by restriction enzyme digestion, and sequenced. Seven patterns were obtained for the tetracycline-resistant colonies, five from L. lactis, and one each from the lactobacilli strains, as well as a single digestion profile for the erythromycin-resistant transformants obtained in L. lactis. Sequence analysis respectively identified tet(S) and ermB in the tetracycline- and erythromycin-resistance plasmids from L. lactis. No dedicated resistance genes were detected in plasmids conferring tetracycline resistance to L. casei and L. plantarum. The present results highlight the usefulness of the proposed methodology for isolating functional plasmids that confer antibiotic resistance to LAB species, widen our knowledge of antibiotic resistance in the bacteria that inhabit cheese, and emphasize the leading role of plasmids in the spread of resistance genes via the food chain. | 2021 | 34360567 |
| 4501 | 4 | 0.9998 | A Bacteroides tetracycline resistance gene represents a new class of ribosome protection tetracycline resistance. The ribosome protection type of tetracycline resistance (Tcr) has been found in a variety of bacterial species, but the only two classes described previously, Tet(M) and Tet(O), shared a high degree of amino acid sequence identity (greater than 75%). Thus, it appeared that this type of resistance emerged recently in evolution and spread among different species of bacteria by horizontal transmission. We obtained the DNA sequence of a Tcr gene from Bacteroides, a genus of gram-negative, obligately anaerobic bacteria that is phylogenetically distant from the diverse species in which tet(M) and tet(O) have been found. The Bacteroides Tcr gene defines a new class of ribosome protection resistance genes, Tet(Q), and has a deduced amino acid sequence that was only 40% identical to Tet(M) or Tet(O). Like tet(M) and tet(O), tet(Q) appears to have spread by horizontal transmission, but only within the Bacteroides group. | 1992 | 1339256 |
| 5993 | 5 | 0.9998 | Genetic basis of erythromycin resistance in oral bacteria. We determined the prevalence of erythromycin-resistant bacteria in the oral cavity and identified mef and erm(B) as the most common resistance determinants. In addition, we demonstrate the genetic linkage, on various Tn1545-like conjugative transposons, between erythromycin and tetracycline resistance in a number of isolates. | 2004 | 15155239 |
| 3568 | 6 | 0.9998 | Occurrence of the new tetracycline resistance gene tet(W) in bacteria from the human gut. Members of our group recently identified a new tetracycline resistance gene, tet(W), in three genera of rumen obligate anaerobes. Here, we show that tet(W) is also present in bacteria isolated from human feces. The tet(W) genes found in human Fusobacterium prausnitzii and Bifidobacterium longum isolates were more than 99.9% identical to those from a rumen isolate of Butyrivibrio fibrisolvens. | 2000 | 10681357 |
| 3577 | 7 | 0.9998 | Intrinsic tet(L) sub-class in Bacillus velezensis and Bacillus amyloliquefaciens is associated with a reduced susceptibility toward tetracycline. Annotations of non-pathogenic bacterial genomes commonly reveal putative antibiotic resistance genes and the potential risks associated with such genes is challenging to assess. We have examined a putative tetracycline tet(L) gene (conferring low level tetracycline resistance), present in the majority of all publicly available genomes of the industrially important operational group Bacillus amyloliquefaciens including the species B. amyloliquefaciens, Bacillus siamensis and Bacillus velezensis. The aim was to examine the risk of transfer of the putative tet(L) in operational group B. amyloliquefaciens through phylogenetic and genomic position analysis. These analyses furthermore included tet(L) genes encoded by transferable plasmids and other Gram-positive and -negative bacteria, including Bacillus subtilis. Through phylogenetic analysis, we could group chromosomally and plasmid-encoded tet(L) genes into four phylogenetic clades. The chromosomally encoded putative tet(L) from operational group B. amyloliquefaciens formed a separate phylogenetic clade; was positioned in the same genomic region in the three species; was not flanked by mobile genetic elements and was not found in any other bacterial species suggesting that the gene has been present in a common ancestor before species differentiation and is intrinsic. Therefore the gene is not considered a safety concern, and the risk of transfer to and expression of resistance in other non-related species is considered negligible. We suggest a subgrouping of the tet(L) class into four groups (tet(L)1.1, tet(L)1.2 and tet(L)2.1, tet(L)2.2), corresponding with the phylogenetic grouping and tet(L) from operational group B. amyloliquefaciens referred to as tet(L)2.2. Phylogenetic analysis is a useful tool to correctly differentiate between intrinsic and acquired antibiotic resistance genes. | 2022 | 35992677 |
| 5995 | 8 | 0.9998 | In vitro conjugal transfer of tetracycline resistance from Lactobacillus isolates to other Gram-positive bacteria. The ability of 14 Lactobacillus strains, isolated from fermented dry sausages, to transfer tetracycline resistance encoded by tet(M) through conjugation was examined using filter mating experiments. Seven out of 14 tetracycline-resistant Lactobacillus isolates were able to transfer in vitro this resistance to Enterococcus faecalis at frequencies ranging from 10(-4) to 10(-6) transconjugants per recipient. Two of these strains could also transfer their resistance to Lactococcus lactis subsp. lactis, whereas no conjugal transfer to a Staphylococcus aureus recipient was found. These data suggest that meat lactobacilli might be reservoir organisms for acquired resistance genes that can be spread to other lactic acid bacteria. In order to assess the risk of this potential hazard, the magnitude of transfer along the food chain merits further research. | 2003 | 12900030 |
| 3569 | 9 | 0.9998 | Identification of a new ribosomal protection type of tetracycline resistance gene, tet(36), from swine manure pits. Previously, only one ribosome protection type of a tetracycline resistance gene, tetQ, had been identified in Bacteroides spp. During an investigation of anaerobic bacteria present in swine feces and manure storage pits, a tetracycline-resistant Bacteroides strain was isolated. Subsequent analysis showed that this new Bacteroides strain, Bacteroides sp. strain 139, did not contain tetQ but contained a previously unidentified tetracycline resistance gene. Sequence analysis showed that the tetracycline resistance gene from Bacteroides sp. strain 139 encoded a protein (designated Tet 36) that defines a new class of ribosome protection types of tetracycline resistance. Tet 36 has 60% amino acid identity over 640 aa to TetQ and between 31 and 49% amino acid identity to the nine other ribosome protection types of tetracycline resistance genes. The tet(36) region was not observed to transfer from Bacteroides sp. strain 139 to another Bacteroides sp. under laboratory conditions. Yet tet(36) was found in other genera of bacteria isolated from the same swine manure pits and from swine feces. Phylogenetic analysis of the tet(36)-containing isolates indicated that tet(36) was present not only in the Cytophaga-Flavobacter-Bacteroides group to which Bacteroides sp. strain 139 belongs but also in gram-positive genera and gram-negative proteobacteria, indicating that horizontal transfer of tet(36) is occurring between these divergent phylogenetic groups in the farm environment. | 2003 | 12839793 |
| 3580 | 10 | 0.9998 | Transfer of plasmid-mediated resistance to tetracycline in pathogenic bacteria from fish and aquaculture environments. The transferability of a large plasmid that harbors a tetracycline resistance gene tet(S), to fish and human pathogens was assessed using electrotransformation and conjugation. The plasmid, originally isolated from fish intestinal Lactococcus lactis ssp. lactis KYA-7, has potent antagonistic activity against the selected recipients (Lactococcus garvieae and Listeria monocytogenes), preventing conjugation. Therefore the tetracycline resistance determinant was transferred via electroporation to L. garvieae. A transformant clone was used as the donor in conjugation experiments with three different L. monocytogenes strains. To our knowledge, this is the first study showing the transfer of an antibiotic resistance plasmid from fish-associated lactic bacteria to L. monocytogenes, even if the donor L. garvieae was not the original host of the tetracycline resistance but experimentally created by electroporation. These results demonstrate that the antibiotic resistance genes in the fish intestinal bacteria have the potential to spread both to fish and human pathogens, posing a risk to aquaculture and consumer safety. | 2009 | 19236483 |
| 5996 | 11 | 0.9997 | Molecular characterization of intrinsic and acquired antibiotic resistance in lactic acid bacteria and bifidobacteria. The minimum inhibitory concentrations (MICs) of 6 different antibiotics (chloramphenicol, clindamycin, erythromycin, streptomycin, tetracycline and vancomycin) were determined for 143 strains of lactic acid bacteria and bifidobacteria using the Etest. Different MICs were found for different species and strains. Based on the distribution of these MIC values, most of the strains were either susceptible or intrinsically resistant to these antibiotics. However, the MIC range of some of these antibiotics showed a bimodal distribution, which suggested that some of the tested strains possess acquired antibiotic resistance. Screening for resistance genes was performed by PCR using specific primers, or using a DNA microarray with around 300 nucleotide probes representing 7 classes of antibiotic resistance genes. The genes identified encoded resistance to tetracycline [tet(M), tet(W), tet(O) and tet(O/W)], erythromycin and clindamycin [erm(B)] and streptomycin [aph(E) and sat(3)]. Internal portions of some of these determinants were sequenced and found to be identical to genes described in other bacteria. All resistance determinants were located on the bacterial chromosome, except for tet(M), which was identified on plasmids in Lactococcus lactis. The contribution of intrinsic multidrug transporters to the antibiotic resistance was investigated by cloning and measuring the expression of Bifidobacterium breve genes in L. lactis. | 2008 | 17957105 |
| 3574 | 12 | 0.9997 | Antibiotic resistances of starter and probiotic strains of lactic acid bacteria. The antibiotic resistances of 45 lactic acid bacteria strains belonging to the genera Lactobacillus, Streptococcus, Lactococcus, Pediococcus, and Leuconostoc were investigated. The objective was to determine antibiotic resistances and to verify these at the genetic level, as is currently suggested by the European "qualified presumption of safety" safety evaluation system for industrial starter strains. In addition, we sought to pinpoint possible problems in resistance determinations. Primers were used to PCR amplify genes involved in beta-lactam antibiotic, chloramphenicol, tetracycline, and erythromycin resistance. The presence of ribosomal protection protein genes and the ermB gene was also determined by using a gene probe. Generally, the incidences of erythromycin, chloramphenicol, tetracycline, or beta-lactam resistances in this study were low (<7%). In contrast, aminoglycoside (gentamicin and streptomycin) and ciprofloxacin resistances were higher than 70%, indicating that these may constitute intrinsic resistances. The genetic basis for ciprofloxacin resistance could not be verified, since no mutations typical of quinolone resistances were detected in the quinolone determining regions of the parC and gyrA genes. Some starter strains showed low-level ampicillin, penicillin, chloramphenicol, and tetracycline resistances, but no known resistance genes could be detected. Although some strains possessed the cat gene, none of these were phenotypically resistant to chloramphenicol. Using reverse transcription-PCR, these cat genes were shown to be silent under both inducing and noninducing conditions. Only Lactobacillus salivarius BFE 7441 possessed an ermB gene, which was encoded on the chromosome and which could not be transferred in filter-mating experiments. This study clearly demonstrates problems encountered with resistance testing, in that the breakpoint values are often inadequately identified, resistance genes may be present but silent, and the genetic basis and associated resistance mechanisms toward some antibiotics are still unknown. | 2007 | 17122388 |
| 3576 | 13 | 0.9997 | Removal of antibiotic resistance gene-carrying plasmids from Lactobacillus reuteri ATCC 55730 and characterization of the resulting daughter strain, L. reuteri DSM 17938. The spread of antibiotic resistance in pathogens is primarily a consequence of the indiscriminate use of antibiotics, but there is concern that food-borne lactic acid bacteria may act as reservoirs of antibiotic resistance genes when distributed in large doses to the gastrointestinal tract. Lactobacillus reuteri ATCC 55730 is a commercially available probiotic strain which has been found to harbor potentially transferable resistance genes. The aims of this study were to define the location and nature of beta-lactam, tetracycline, and lincosamide resistance determinants and, if they were found to be acquired, attempt to remove them from the strain by methods that do not genetically modify the organism before subsequently testing whether the probiotic characteristics were retained. No known beta-lactam resistance genes was found, but penicillin-binding proteins from ATCC 55730, two additional resistant strains, and three sensitive strains of L. reuteri were sequenced and comparatively analyzed. The beta-lactam resistance in ATCC 55730 is probably caused by a number of alterations in the corresponding genes and can be regarded as not transferable. The strain was found to harbor two plasmids carrying tet(W) tetracycline and lnu(A) lincosamide resistance genes, respectively. A new daughter strain, L. reuteri DSM 17938, was derived from ATCC 55730 by removal of the two plasmids, and it was shown to have lost the resistances associated with them. Direct comparison of the parent and daughter strains for a series of in vitro properties and in a human clinical trial confirmed the retained probiotic properties of the daughter strain. | 2008 | 18689509 |
| 3573 | 14 | 0.9997 | Antibiotic Susceptibility Profiles of Lactic Acid Bacteria from the Human Vagina and Genetic Basis of Acquired Resistances. Lactic acid bacteria can act as reservoirs of antibiotic resistance genes that can be ultimately transferred to pathogens. The present work reports on the minimum inhibitory concentration (MIC) of 16 antibiotics to 25 LAB isolates of five Lactobacillus and one Bifidobacterium species from the human vagina. Acquired resistances were detected to kanamycin, streptomycin, chloramphenicol, gentamicin, and ampicillin. A PCR analysis of lactobacilli failed to identify genetic determinants involved in any of these resistances. Surprisingly, a tet(W) gene was detected by PCR in two Bifidobacterium bifidum strains, although they proved to be tetracycline-susceptible. In agreement with the PCR results, no acquired genes were identified in the genome of any of the Lactobacillus spp. strains sequenced. A genome analysis of B. bifidum VA07-1AN showed an insertion of two guanines in the middle of tet(W) interrupting the open reading frame. By growing the strain in the presence of tetracycline, stable tetracycline-resistant variants were obtained. An amino acid substitution in the ribosomal protein S12 (K43R) was further identified as the most likely cause of VA07-1AN being streptomycin resistance. The results of this work expand our knowledge of the resistance profiles of vaginal LAB and provide evidence for the genetic basis of some acquired resistances. | 2020 | 32276519 |
| 5962 | 15 | 0.9997 | Functional screening of antibiotic resistance genes from human gut microbiota reveals a novel gene fusion. The human gut microbiota has a high density of bacteria that are considered a reservoir for antibiotic resistance genes (ARGs). In this study, one fosmid metagenomic library generated from the gut microbiota of four healthy humans was used to screen for ARGs against seven antibiotics. Eight new ARGs were obtained: one against amoxicillin, six against d-cycloserine, and one against kanamycin. The new amoxicillin resistance gene encodes a protein with 53% identity to a class D β-lactamase from Riemerella anatipestifer RA-GD. The six new d-cycloserine resistance genes encode proteins with 73-81% identity to known d-alanine-d-alanine ligases. The new kanamycin resistance gene encodes a protein of 274 amino acids with an N-terminus (amino acids 1-189) that has 42% identity to the 6'-aminoglycoside acetyltransferase [AAC(6')] from Enterococcus hirae and a C-terminus (amino acids 190-274) with 35% identity to a hypothetical protein from Clostridiales sp. SSC/2. A functional study on the novel kanamycin resistance gene showed that only the N-terminus conferred kanamycin resistance. Our results showed that functional metagenomics is a useful tool for the identification of new ARGs. | 2012 | 22845886 |
| 3597 | 16 | 0.9997 | Evidence for extensive resistance gene transfer among Bacteroides spp. and among Bacteroides and other genera in the human colon. Transfer of antibiotic resistance genes by conjugation is thought to play an important role in the spread of resistance. Yet virtually no information is available about the extent to which such horizontal transfers occur in natural settings. In this paper, we show that conjugal gene transfer has made a major contribution to increased antibiotic resistance in Bacteroides species, a numerically predominant group of human colonic bacteria. Over the past 3 decades, carriage of the tetracycline resistance gene, tetQ, has increased from about 30% to more than 80% of strains. Alleles of tetQ in different Bacteroides species, with one exception, were 96 to 100% identical at the DNA sequence level, as expected if horizontal gene transfer was responsible for their spread. Southern blot analyses showed further that transfer of tetQ was mediated by a conjugative transposon (CTn) of the CTnDOT type. Carriage of two erythromycin resistance genes, ermF and ermG, rose from <2 to 23% and accounted for about 70% of the total erythromycin resistances observed. Carriage of tetQ and the erm genes was the same in isolates taken from healthy people with no recent history of antibiotic use as in isolates obtained from patients with Bacteroides infections. This finding indicates that resistance transfer is occurring in the community and not just in clinical environments. The high percentage of strains that are carrying these resistance genes in people who are not taking antibiotics is consistent with the hypothesis that once acquired, these resistance genes are stably maintained in the absence of antibiotic selection. Six recently isolated strains carried ermB genes. Two were identical to erm(B)-P from Clostridium perfringens, and the other four had only one to three mismatches. The nine strains with ermG genes had DNA sequences that were more than 99% identical to the ermG of Bacillus sphaericus. Evidently, there is a genetic conduit open between gram-positive bacteria, including bacteria that only pass through the human colon, and the gram-negative Bacteroides species. Our results support the hypothesis that extensive gene transfer occurs among bacteria in the human colon, both within the genus Bacteroides and among Bacteroides species and gram-positive bacteria. | 2001 | 11157217 |
| 4612 | 17 | 0.9997 | Assessment of tetracycline and erythromycin resistance transfer during sausage fermentation by culture-dependent and -independent methods. The food chain is considered one of the main routes of antibiotic resistance diffusion between animal and human population. The resistance to antimicrobial agents among enterococci could be related to the efficient exchange of transferable genetic elements. In this study a sausage model was used to evaluate the persistence of antibiotic resistant enterococci during meat fermentation and to assess horizontal gene transfer among bacteria involved in meat fermentation. Enterococcus faecalis OG1rf harbouring either pCF10 or pAMβ1 plasmid was used as donor strain. The analysis of population dynamics during fermentation confirmed that the human isolate E. faecalis OG1rf was able to colonize the meat ecosystem with similar growth kinetics to that of food origin enterococci and to transfer the mobile genetic elements coding for tetracycline and erythromycin resistances. Transconjugant strains were detected after only two days of fermentation and increased their numbers during ripening even in the absence of selective antibiotic pressure. By means of culture-dependent and -independent molecular techniques, transconjugant strains carrying both tetracycline and erythromycin resistance genes were identified in enterococci, pediococci, lactobacilli and staphylococci groups. Our results suggest that the sausage model provides a suitable environment for horizontal transfer of conjugative plasmids and antibiotic resistance genes among food microbiota. | 2012 | 22365347 |
| 4613 | 18 | 0.9997 | Glycopeptide-resistance transferability from vancomycin-resistant enterococci of human and animal source to Listeria spp. AIMS: The glycopeptide-resistance transferability from vancomycin-resistant enterococci (VRE) of clinical and animal origin to different species of Listeria was investigated. METHODS AND RESULTS: Of 36 matings, performed on membrane filter, the glycopeptide resistance was successfully transferred in six attempts, five with donors of animal origin and only one with donors from clinical source. The acquired glycopeptide resistance in Listeria transconjugants was confirmed by the presence of the conjugative plasmid band and by the amplification of the 732-bp fragment of vanA gene in transferred plasmids. CONCLUSIONS: Despite the lower number of bacteria used in this study, the source of enterococci influenced the outcome of mating. Moreover transferred VanA plasmid induced a different expression in Listeria transconjugants, suggesting that gene expression might be influenced by species affiliation of recipients. SIGNIFICANCE AND IMPACT OF THE STUDY: Our data strengthen the opinion that enterococci are an important source of resistance genes for Listeria via the transfer of movable genetic elements. As these strains are commonly found in the same habitats, a horizontal spread of glycopeptide resistance in Listeria spp. could be possible. | 2004 | 15548299 |
| 4605 | 19 | 0.9997 | Self-transmissible multidrug resistance plasmids in Escherichia coli of the normal intestinal flora of healthy swine. The resistance genes and their surroundings on three self-transmissible plasmids found in Escherichia coli of the enteric normal flora of healthy pigs have been characterized. The resistance elements found are similar to those commonly found in clinical isolates, like the transposon Tn1721 including the Tet A tetracycline resistance determinant, Tn10 with the Tet B determinant, Tn21 including a class 1 integron with the aadA1a cassette inserted, sulII encoding sulfonamide resistance, and the strA-strB genes responsible for streptomycin resistance. The plasmids were able to mobilize into various recipients, including swine pathogens, zoonotic bacteria, and commensals when conjugation experiments were carried out. Transfer of plasmids did not require optimal conditions concerning nutrition and temperature as plasmids were transferred in 0.9% saline at room temperature, suggesting that in vivo transfer might be possible. This study shows that transferable resistance elements appearing in normal flora bacteria from animals are similar to those commonly found in clinical isolates of human origin. The results indicate a probable communication between pathogens and the normal flora with respect to exchange of resistance factors. | 2001 | 11442346 |