# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 5899 | 0 | 0.9895 | Identification of strA-strB Genes in Streptomycin-Resistant Pseudomonas syringae pv. actinidiae Biovar 2 Strains Isolated in Korea. Bacterial canker is a devastating disease of kiwifruit caused by the bacterium Pseudomonas syringe pv. actinidiae. Canker disease of kiwifruit in Korea has been controlled using streptomycin for more than two decades. Four streptomycin-resistant strains, belonging to biovar 2, which are found only in Korea, were collected between 2013 and 2014 from different orchards located in Jeju, Korea. The genetic background for streptomycin resistance among P. syringe pv. actinidiae strains were determined by examining the presence of strA-strB or aadA, which are genes frequently found in streptomycin-resistant bacteria, and a point mutation at codon 43 in the rpsL gene. All four streptomycin-resistant strains of P. syringe pv. actinidiae investigated in this study contained strA-strB as a resistant determinant. The presence of the aadA gene and a mutation in codon 43 of the rpsL gene was not identified. | 2021 | 34847635 |
| 434 | 1 | 0.9895 | Homologous Streptomycin Resistance Gene Present among Diverse Gram-Negative Bacteria in New York State Apple Orchards. The streptomycin resistance gene of Pseudomonas syringae pv. papulans Psp36 was cloned into Escherichia coli and used to develop a 500-bp DNA probe that is specific for streptomycin resistance in P. syringae pv. papulans. The probe is a portion of a 1-kb region shared by three different DNA clones of the resistance gene. In Southern hybridizations, the probe hybridized only with DNA isolated from streptomycin-resistant strains of P. syringae pv. papulans and not with the DNA of streptomycin-sensitive strains. Transposon insertions within the region of DNA shared by the three clones resulted in loss of resistance to streptomycin. Colony hybridization of bacteria isolated from apple leaves and orchard soil indicated that 39% of 398 streptomycin-resistant bacteria contained DNA that hybridized to the probe. These included all strains of P. syringae pv. papulans and some other fluorescent pseudomonads and nonfluorescent gram-negative bacteria, but none of the gram-positive bacteria. The same-size restriction fragments hybridized to the probe in P. syringae pv. papulans. Restriction fragment length polymorphism of this region was occasionally observed in strains of other taxonomic groups of bacteria. In bacteria other than P. syringae pv. papulans, the streptomycin resistance probe hybridized to different-sized plasmids and no relationship between plasmid size and taxonomic group or between plasmid size and orchard type, soil association, or leaf association could be detected. | 1991 | 16348415 |
| 5861 | 2 | 0.9894 | Distribution of genes conferring combined resistance to tetracycline and minocycline among group B streptococcal isolates from humans and various animals. Forty-nine tetracycline and minocycline resistant streptococci of serological group B isolated from humans, cattle, pigs and nutrias were investigated for the presence of genes conferring this combined resistance. Southern blot hybridization of EcoRI-digested chromosomal DNA of the bacteria revealed for 39 of the cultures a hybridization signal with tet(M), for four of the cultures a hybridization signal with tet(O) and for none of the cultures a hybridization signal with the tet(Q) gene probe. The restriction endonuclease digested and blotted DNA of six tetracycline and minocycline resistant group B streptococci did not hybridize with any of the available gene probes. The tet(M) gene probes recognized complementary sequences of EcoRI fragments of approximately 10.5 kb and 21.5 kb, the tet(O) gene probe hybridized with fragments of approximately 19 kb. The hybridization of the tet(M) gene probe in two different patterns appeared to be related to the origin of the cultures. | 1994 | 7727901 |
| 3652 | 3 | 0.9894 | Distribution of Transferable Antibiotic Resistance Genes in Laboratory-Reared Edible Mealworms (Tenebrio molitor L.). In the present study, the distribution of antibiotic resistance genes in laboratory-reared fresh mealworm larvae (Tenebrio molitor L.), their feeding substrates (carrots and wheatmeal), and frass was assessed. Microbial counts on selective media added with antibiotics highlighted the presence of lactic acid bacteria resistant to ampicillin and vancomycin and, more specifically, enterococci resistant to the latter antibiotic. Moreover, staphylococci resistant to gentamicin, erythromycin, tetracycline, and vancomycin were detected. Enterobacteriaceae resistant to ampicillin and gentamicin were also found, together with Pseudomonadaceae resistant to gentamicin. Some of the genes coding for resistance to macrolide-lincosamide-streptogramin B (MLS(B)) [erm(A), erm(C)], vancomycin [vanA, vanB], tetracycline [tet(O)], and β-lactams [mecA and blaZ] were absent in all of the samples. For the feeding substrates, organic wheatmeal was positive for tet(S) and tet(K), whereas no AR genes were detected in organic carrots. The genes tet(M), tet(K), and tet(S) were detected in both mealworms and frass, whereas gene aac-aph, coding for resistance to amynoglicosides was exclusively detected in frass. No residues for any of the 64 antibiotics belonging to 10 different drug classes were found in either the organic wheatmeal or carrots. Based on the overall results, the contribution of feed to the occurrence of antibiotic resistance (AR) genes and/or antibiotic-resistant microorganisms in mealworm larvae was hypothesized together with vertical transmission via insect egg smearing. | 2018 | 30510544 |
| 2884 | 4 | 0.9894 | Gilthead seabream (Sparus aurata) carrying antibiotic resistant enterococci. A potential bioindicator of marine contamination? Antibiotic resistance in bacteria is a growing problem that is not only restricted to the clinical setting but also to other environments such as marine species that harbor antibiotic resistant bacteria and therefore may serve as reservoirs for antibiotic-resistance genetic determinants. The aim of this study was to evaluate antibiotic resistance phenotypes in enterococci isolated from fecal samples of gilthead seabream and the associated mechanisms of resistance. A collection of 118 samples were analyzed and 73 enterococci were recovered. The strains showed high percentages of resistance to erythromycin and tetracycline (58.9% and 17.8%, respectively). Lower level of resistance (<13%) was detected for quinupristin-dalfopristin, ampicillin, high-level-gentamicin, high-level-streptomycin, high-level-kanamycin, ciprofloxacin and chloramphenicol. The erm(B), tet(L) or tet(M), aac(6')-aph(2″) and aph(3')-IIIa genes were shown in isolates resistant to erythromycin, tetracycline, high-level gentamicin and high-level kanamycin, respectively. Antibiotic resistance in natural microbiota is becoming a concern of human and environmental health. | 2011 | 21511306 |
| 6165 | 5 | 0.9893 | Evaluation of kasugamycin for fire blight management, effect on nontarget bacteria, and assessment of kasugamycin resistance potential in Erwinia amylovora. The emergence and spread of streptomycin-resistant strains of Erwinia amylovora in Michigan has necessitated the evaluation of new compounds effective for fire blight control. The aminoglycoside antibiotic kasugamycin (Ks) targets the bacterial ribosome and is particularly active against E. amylovora. The efficacy of Ks formulated as Kasumin 2L for control of fire blight was evaluated in six experiments conducted over four field seasons in our experimental orchards in East Lansing, MI. Blossom blight control was statistically equivalent to the industry standard streptomycin in all experiments. E. amylovora populations remained constant on apple flower stigmas pretreated with Kasumin and were ≈100-fold lower than on stigmas treated with water. Kasumin applied to apple trees in the field also resulted in a 100-fold reduced total culturable bacterial population compared with trees treated with water. We performed a prospective analysis of the potential for kasugamycin resistance (Ks(R)) development in E. amylovora which focused on spontaneous resistance development and acquisition of a transferrable Ks(R) gene. In replicated lab experiments, the development of spontaneous resistance in E. amylovora to Ks at 250 or 500 ppm was not observed when cells were directly plated on medium containing high concentrations of the antibiotic. However, exposure to increasing concentrations of Ks in media (initial concentration 25 μg ml(-1)) resulted in the selection of Ks resistance (at 150 μg ml(-1)) in the E. amylovora strains Ea110, Ea273, and Ea1189. Analysis of mutants indicated that they harbored mutations in the kasugamycin target ksgA gene and that all mutants were impacted in relative fitness observable through a reduced growth rate in vitro and decreased virulence in immature pear fruit. The possible occurrence of a reservoir of Ks(R) genes in orchard environments was also examined. Culturable gram-negative bacteria were surveyed from six experimental apple orchards that had received at least one Kasumin application. In total, 401 Ks(R) isolates (42 different species) were recovered from apple flowers and leaves and orchard soil samples. Although we have not established the presence of a transferrable Ks(R) gene in orchard bacteria, the frequency, number of species, and presence of Ks(R) enterobacterial species in orchard samples suggests the possible role of nontarget bacteria in the future transfer of a Ks(R) gene to E. amylovora. Our data confirm the importance of kasugamycin as an alternate antibiotic for fire blight management and lay the groundwork for the development and incorporation of resistance management strategies. | 2011 | 20923369 |
| 3628 | 6 | 0.9891 | Antibiotic resistance patterns of gram-negative bacteria isolated from environmental sources. A total of 2,445 gram-negative bacteria belonging to fecal coliform, Pseudomonas, Moraxella, Acinetobacter, and Flavobacterium-Cytophaga groups were isolated from the rivers and bay of Tillamook, Oregon, and their resistances to chloramphenicol (25 microgram/ml), streptomycin (10 microgram/ml), ampicillin (10 microgram/ml), tetracycline (25 microgram/ml), chlortetracycline (25 microgram/ml), oxytetracycline (25 microgram/ml), neomycin (50 microgram/ml), nitrofurazone (12.5 microgram/ml), nalidixic acid (25 microgram/ml), kanamycin (25 microgram/ml), and penicillin G (10 IU/ml) were determined. Among fecal coliforms the bay isolates showed greater resistance to antibiotics than those from tributaries or surface runoff. No such well-defined difference was found among other bacterial groups. The antibiotic resistance patterns of gram-negative bacteria from different sources correlated well, perhaps indicating their common origin. The antibiotic resistance patterns of gram-negative bacteria of different general also correlated well, perhaps indicating that bacteria which share a common environment also share a common mode for developing antibiotic resistance. | 1978 | 727777 |
| 3587 | 7 | 0.9891 | Distribution of the streptomycin-resistance transposon Tn5393 among phylloplane and soil bacteria from managed agricultural habitats. The distribution of the strA-strB streptomycin-resistance (Smr) genes associated with Tn5393 was examined in bacteria isolated from the phylloplane and soil of ornamental pear and tomato. Two ornamental pear nurseries received previous foliar applications of streptomycin, whereas the tomato fields had no prior exposure to streptomycin bactericides. Although the recovery of culturable Smr bacteria was generally higher from soil, the highest occurrence of Smr was observed in phylloplane bacteria of an ornamental pear nursery that received 15 annual applications of streptomycin during the previous 2 years. Twenty-two and 12% of 143 Gram-negative phylloplane and 163 Gram-negative soil isolates, respectively, contained sequences that hybridized to probes specific for the strA-strB Smr genes and for the transposase and resolvase genes of Tn5393. These sequences were located on large plasmids (> 60 kb) in 74% of the isolates. The 77 Smr Gram-positive bacteria isolated in the present study showed no homology to the Tn5393-derived probes. Although the repeated use of a single antibiotic in clinical situations is known to favor the development of strains with resistance to other antibiotics, we found no evidence that intensive streptomycin usage in agricultural habitats favors the development of resistance to tetracycline, an antibiotic also registered for disease control on plants. The detection of Tn5393 in bacteria with no prior exposure to streptomycin suggests that this transposon is indigenous to both phylloplane and soil microbial communities. | 1995 | 7585356 |
| 3640 | 8 | 0.9890 | Antibiotic resistant bacteria in fish from the Concepción Bay, Chile. Antibiotic resistant bacteria from commercial demersal and pelagic fish captured in the Concepción Bay, Chile were investigated. Viable counts of antibiotic resistant bacteria isolated from gill and intestinal content samples showed high frequencies of resistance to ampicillin, streptomycin and tetracycline, while the proportion of chloramphenicol resistance was rather low. A high incidence of resistance to ampicillin, streptomycin, tetracycline and nitrofurantoin, as well as almost an absence of resistance to gentamicin, amikacin and cotrimoxazole was found among selected isolates which represented the resistant bacterial population. These strains mainly belonged to Vibrionaceae and Enterobacteriaceae and were predominantly resistant to 3 and 4 antibacterials. Isolates from demersal fish exhibited resistance to as many as 8-10 compounds, whereas those from pelagic fish were resistant to seven or fewer antibiotics. These results suggest that Chilean commercial fishes residing in waters near the disposals of urban sewage might play a role as carriers of antibiotic resistant bacteria prompting a health risk to public health for fish consumers. | 2001 | 11763221 |
| 5241 | 9 | 0.9890 | Antibiotic resistance marker genes as environmental pollutants in GMO-pristine agricultural soils in Austria. Antibiotic resistance genes may be considered as environmental pollutants if anthropogenic emission and manipulations increase their prevalence above usually occurring background levels. The prevalence of aph(3')-IIa/nptII and aph(3')-IIIa/nptIII - frequent marker genes in plant biotechnology conferring resistance to certain aminoglycosides - was determined in Austrian soils from 100 maize and potato fields not yet exposed to but eligible for GMO crop cultivation. Total soil DNA extracts were analysed by nptII/nptIII-specific TaqMan real time PCR. Of all fields 6% were positive for nptII (median: 150 copies/g soil; range: 31-856) and 85% for nptIII (1190 copies/g soil; 13-61600). The copy-number deduced prevalence of nptIII carriers was 14-fold higher compared to nptII. Of the cultivable kanamycin-resistant soil bacteria 1.8% (95% confidence interval: 0-3.3%) were positive for nptIII, none for nptII (0-0.8%). The nptII-load of the studied soils was low rendering nptII a typical candidate as environmental pollutant upon anthropogenic release into these ecosystems. | 2015 | 26232739 |
| 3669 | 10 | 0.9890 | Detection of clinically relevant antimicrobial resistance determinants in warm-blooded marine animals in Livingston Island (South Shetland Islands, Antarctica): A field-based molecular genetics study. Molecular genetic studies of stools were performed to assess the spread of some clinically relevant antimicrobial resistance determinants (ARD) in a gentoo penguin (Pygoscelis papua) and an Antarctic fur seal (Arctocephalus gazella) on Livingston Island. Glycopeptide resistance genes (vanA/vanD and vanB) were detected in both fecal samples, while the penguin's one was also mecA-positive and bla(NDM)-positive. Because of the remoteness and the isolation of the sampling locations, the carriage of vancomycin-resistant Enterococcus spp., methicillin-resistant Staphylococcus aureus, and NDM-producing Enterobacterales or other gram-negative bacilli suggested an ocean pollution with antibiotic resistant bacteria (ARB). Additionally, due to the type of ARD we detected, our results are alarming, and they cannot be explained only with agricultural and/or aquacultural pollution. Even though the current study is a preliminary one, it also demonstrates the potential of the field genetics analyses carried out with minimal equipment as a reliable monitoring tool for pollution with ARB. | 2022 | 35597002 |
| 3661 | 11 | 0.9890 | Susceptibility of meat starter cultures to antimicrobials used in food animals in Canada. Lactic acid bacteria (LAB) are extensively used in the food industry for fermentation processes. However, it is possible that these bacteria may serve as a reservoir for antibiotic resistance genes that can be transferred to pathogens, giving rise to public health concerns. Animal operations that use antimicrobials as growth promotants have been linked to the origin of resistance due to the selective effect of low levels of antimicrobial used in this management strategy. The objective of this study was to determine the antimicrobial susceptibilities and mechanisms of resistance for 30 isolates of meat starter cultures commonly used in dry sausage fermentations to 20 antimicrobial agents. Susceptibility tests were performed by broth microdilution using Iso-Sensitest broth (90%, vol/vol) and de Man Rogosa Sharpe (MRS) broth (10%, vol/vol). The results showed that all 30 isolates exhibited resistance to at least three antimicrobials regardless of antimicrobial class while 17 or 30% of strains were resistant to antibiotics in three or six different classes, respectively. The incidence of antimicrobial resistance was higher among Pediococcus pentosaceus and lower for Staphylococcus carnosus strains. Genetic determinants for the lincosamide, macrolide, and tetracycline antimicrobials were not found using PCR. Phenotypic resistance in the absence of known resistance genes found here suggests that other mechanisms or genes might have contributed to the negative results. Further studies are needed to explore the genetic mechanisms underlying the prevalence of antibiotic resistance in Pediococcus species. | 2010 | 20501043 |
| 5445 | 12 | 0.9890 | Antibiotic 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. | 2018 | 30081345 |
| 5939 | 13 | 0.9889 | Resistance to antimicrobial agents of common bacteria isolated from Taiwan. Antimicrobial susceptibility of 11 commonly seen and/or important pathogenic bacteria isolated from the National Taiwan University Hospital in 1981 and 1992 was analysed. Oxacillin-resistance was most remarkable in Staphylococcus aureus. Its prevalence increased rapidly from 6.7% in 1981 to 49.7% in 1992. A high proportion of oxacillin-resistance was also found in coagulase-negative staphylococci, both in 1981 and in 1992. For Streptococcus pneumoniae, no penicillin-resistant nor erythromycin-resistant strain was found in 1981, but by 1992, 5.8% of the isolates were penicillin-resistant 42.3% erythromycin-resistant. Gentamicin-resistance was the most common problem in enterococci, with 70.6% resistance in 1992. As to Gram-negative bacteria, Enterobacter spp. demonstrated a high proportion of resistance to various antimicrobial agents: more than 72% susceptibility was found only for amikacin. Pseudomonas aeruginosa was also a highly resistant bacterium, with only 50 to 90% of susceptibility to various antipseudomonal agents. In Haemophilus influenzae, both ampicillin-resistance and chloramphenicol-resistance were remarkable, with 52.2% and 32.9% resistance, respectively, in 1992. | 1994 | 18611604 |
| 406 | 14 | 0.9889 | Naturally occurring macrolide-lincosamide-streptogramin B resistance in Bacillus licheniformis. Resistance to the macrolide-lincosamide-streptogramin B (MLS) group of antibiotics is widespread and of clinical importance. B. Weisblum and his coworkers have demonstrated that this resistance is associated with methylation of the 23S ribosomal ribonucleic acid of the large ribosomal subunit which results in a diminished affinity of this organelle for these antibiotics (Lai et al, J. Mol. Biol. 74:67-72, 1973). We report that 10 of 15 natural isolates of Bacillus licheniformis, a common soil organism, are resistant to the MLS antibiotics. The properties of this resistance (high level of tolerance for erythromycin, broad cross-resistance spectrum, and inducibility) suggest that resistance is conferred as described above. The resistance determinant from one of these strains was cloned onto a B. subtilis plasmid vector, and the resulting hybrid plasmid (pBD90) was used to prepare radioactive probe deoxyribonucleic acid for hybridization studies. All of the resistance B. licheniformis strains studied exhibited homology with the pBD90 insert. Plasmid pBD90 showed no homology to the following staphylococcal and streptococcal MLS-resistance plasmids: pE194, pE5, pAM77, pI258. Plasmids pE194 and pE5, on the other hand, carry homologous MLS genes but showed no detectable homology to one another in their replication genes. pBD90 specified a 35,000-dalton erythromycin-inducible protein, detectable in minicells, which therefore appears different from the 29,000-dalton inducible resistance protein specified by pE194. We conclude that there are at least three distinct MLS resistance determinants to be found among gram-positive bacteria. | 1981 | 6780509 |
| 5443 | 15 | 0.9889 | Antibiotic resistance of Vibrio species isolated from Sparus aurata reared in Italian mariculture. Extensive use of antimicrobial agents in finfish farming and the consequent selective pressure lead to the acquisition of antibiotic resistance in aquaculture environment bacteria. Vibrio genus represents one of the main pathogens affecting gilthead sea bream. The development of antibiotic resistance by Vibrio represents a potential threat to human health by exchange of resistant genes to human pathogens through food chain. The objective of the present study was to conduct a multisite survey on the antibiotic resistance of Vibrio spp. isolated from gilthead sea bream reared in Italian mariculture. Vibrio spp. strains were isolated from skin, gills, muscles and intestinal content of 240 gilthead sea bream. A random selection of 150 strains was sequenced for species identification. Resistance against 15 antimicrobial agents was tested by the broth microdilution method. Vibrio harveyi and Vibrio alginolyticus accounted for 36.7% and 33.3% of the isolates respectively. 96% of the strains showed multiple resistance to the tested drugs, with two strains, Vibrio aestuarianus and Vibrio harveyi resistant to 10 and 9 antibiotics, respectively. Ampicillin, amoxicillin, erythromycin and sulfadiazine showed low efficacy against Vibrio spp. Rational use of antimicrobial agents and surveillance on antibiotic administration may reduce the acquisition of resistance by microorganisms of aquatic ecosystems. | 2014 | 25180847 |
| 2438 | 16 | 0.9889 | Detection of Staphylococcus aureus and their toxin genes inhabit on the scorpions surface. The transmission of infectious agents by arthropods is of particular importance. Every year, many people are bitten by scorpions around the world. Staphylococcus aureus is of the most important infectious bacteria. This study aimed to investigate the distribution of S. aureus in scorpion specimens and the presence of some toxin genes in these species. The fauna of scorpions in the Kuhdasht region was studied for one year. Then, S. aureus was identified on the body surface of scorpions by biochemical and molecular methods, and the presence of Sea, Seb, Sec, Sed, See, Pvl, Tsst1, Eta, Etb, and mecA genes was examined by the PCR method. The pattern of antibiotic resistance was determined by the use disk diffusion method. MRSA isolates were identified using genotypic and phenotypic methods. Of 75 studied scorpion specimens, Hottentotta saulcyi was the most abundant species. Sixteen (21.3%) isolates of S. aureus were identified from all samples. The highest and lowest antibiotic resistance levels belonged to penicillin and clindamycin, respectively. MRSA was observed in 50% of the isolates. Thirteen out of 16 isolates possessed at least one of the toxin genes. Due to the presence of S. aureus on the body surface of scorpions, it should always be expected that an infection may occur after the bite. Moreover, the presence of toxin genes in the studied isolates showed that infection with these bacteria would seriously threaten one's health. | 2022 | 36018402 |
| 2800 | 17 | 0.9889 | Occurrence of tetracycline resistance genes tet(M) and tet(S) in bacteria from marine aquaculture sites. Occurrence of tetracycline resistance genes encoding ribosomal protection proteins was examined in 151 tetracycline-resistant bacterial isolates from fish and seawater at coastal aquaculture sites in Japan and Korea. The tet(M) gene was detected in 34 Japanese and Korean isolates, which included Vibrio sp., Lactococcus garvieae, Photobacterium damsela subsp. piscicida, and unidentified Gram-positive bacteria. The majority of these bacterial isolates displayed high-level resistance with a minimum inhibitory concentrations (MICs) equal to or greater than 250 microg/ml of oxytetracycline and only four isolates had MICs less than 31.3 microg/ml. 16S rDNA RFLP typing of tet(M)-positive Vibrio isolates suggests that these are clonal populations of the same phylotype specific to a particular location. One Vibrio clone (phylotype III), however, is widely disseminated, being detected during different sampling years, at different locations, and in different fish species in both Japan and Korea. The tet(S) gene was detected in L. garvieae from yellowtail in Japan and in Vibrio sp. from seawater in Korea. This is the first report of tet(S) occurrence in Gram-negative facultative anaerobes. These results suggest that tet(M) and tet(S) genes are present in fish intestinal and seawater bacteria at aquaculture sites and could be an important reservoir of tetracycline resistance genes in the marine environment. | 2004 | 15268950 |
| 821 | 18 | 0.9889 | DNA probes for studying streptothricin resistance evolution in enteric bacteria. Probes for the detection of streptothricin resistance genes have been derived from recombinant plasmids. These include the streptothricin resistance gene probe sat 1/2 derived from Tn 1826 and specific for both the sat-1 determinant of Tn 1825 and the sat-2 determinant of Tn 1826, and the probe sat D derived from and specific for the sat-1 determinant of transposon Tn 1825. A third streptothricin resistance gene probe, sat 3, represents the streptothricin resistance determinant sat-3 of the IncQ R plasmid pIE639. Hybridization studies did not reveal any sequence homology between sat-3 and the transposon-localized sat-1 and sat-2 determinants. Moreover, non of the different sat-determinants isolated from plasmids of gram negative bacteria hybridized with the analogous resistance determinant of Streptomyces noursei, which had been cloned and named nat by Krügel et al. (Gene, 1988, 62, 209-214). The sat 1/2 probe in combination with the sat D probe proved to be suitable for the identification and the differentiation of sat-1 and sat-2 determinants in different genetic environments. Streptothricin resistance genes related to those present on transposons Tn 1825 and Tn 1826 have been detected by hybridization with the probe sat 1/2 on plasmids isolated a long time ago before the application of streptothricins. The sat-3 determinant appears to be exclusively associated with the IncQ plasmid pIE639. | 1990 | 2166786 |
| 2795 | 19 | 0.9889 | Molecular identification and quantification of tetracycline and erythromycin resistance genes in Spanish and Italian retail cheeses. Large antibiotic resistance gene pools in the microbiota of foods may ultimately pose a risk for human health. This study reports the identification and quantification of tetracycline- and erythromycin-resistant populations, resistance genes, and gene diversity in traditional Spanish and Italian cheeses, via culturing, conventional PCR, real-time quantitative PCR (qPCR), and denaturing gradient gel electrophoresis (DGGE). The numbers of resistant bacteria varied widely among the antibiotics and the different cheese varieties; in some cheeses, all the bacterial populations seemed to be resistant. Up to eight antibiotic resistance genes were sought by gene-specific PCR, six with respect to tetracycline, that is, tet(K), tet(L), tet(M), tet(O), tet(S), and tet(W), and two with respect to erythromycin, that is, erm(B) and erm(F). The most common resistance genes in the analysed cheeses were tet(S), tet(W), tet(M), and erm(B). The copy numbers of these genes, as quantified by qPCR, ranged widely between cheeses (from 4.94 to 10.18log10/g). DGGE analysis revealed distinct banding profiles and two polymorphic nucleotide positions for tet(W)-carrying cheeses, though the similarity of the sequences suggests this tet(W) to have a monophyletic origin. Traditional cheeses would therefore appear to act as reservoirs for large numbers of many types of antibiotic resistance determinants. | 2014 | 25302306 |