# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 1337 | 0 | 0.8921 | Biofilm formation, antimicrobial assay, and toxin-genotypes of Clostridium perfringens type C isolates cultured from a neonatal Yangtze finless porpoise. This is a culture-dependent study with the objective of pure culturing and characterizing pathogenic bacteria from the blowhole, lung, stomach and fecal samples of a neonatal crucially endangered Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis) that died 27 days after birth. Bacteria were inoculated using a swab onto blood and MacConkey agar plates and representative isolates were identified through 16S rRNA gene sequence analysis. A total of three Clostridium perfringens type C strains from the fecal samples were isolated. Toxin genes, including cpa, cpb and cpb2, were detected by PCR amplification, whereas the etx, iap and cpe genes were not detected. Biofilm formation of the three strains was then examined. Only one strain was capable of biofilm formation. In addition, isolates showed strong resistance against the antibiotics amikacin (3/3), erythromycin (1/3), gentamicin (3/3), streptomycin (3/3), and trimethoprim (3/3), while sensitivity to ampicillin (3/3), bacitracin (3/3), erythromycin (2/3), penicillin G (3/3), and tetracycline (3/3). The results suggested C. perfringens type C could have contributed to the death of this neonatal porpoise. | 2022 | 35662380 |
| 5222 | 1 | 0.8874 | Resistance to macrolides by ribosomal mutation in clinical isolates of Turicella otitidis. The genetic basis of erythromycin resistance in Turicella otitidis, a coryneform bacteria associated with otitis, was studied in five macrolide-resistant clinical isolates. Macrolide resistance genes were searched for by polymerase chain reaction (PCR). Genes for domain V of 23S rRNA (rrl) as well as rplD (L4 protein) and rplV (L22 protein) genes were characterised, amplified by PCR from total genomic DNA and sequenced. In the resistant isolates, cross-resistance to macrolides and clindamycin was associated with mutations at positions 2058 and/or 2059 (Escherichia coli numbering). Three isolates displayed A2058 mutations, one isolate had an A2059G mutation whereas another one contained mutations at positions 2058 and 2059. Southern blot experiments revealed that T. otitidis had three copies of the rrl gene. In conclusion, resistance to macrolides in T. otitidis is due, at least in part, to mutations in the rrl gene. | 2009 | 19414240 |
| 5233 | 2 | 0.8867 | Antibiotic resistance pattern of the allochthonous bacteria isolated from commercially available spices. Spices are often used in dried form, sometimes with significant microbial contamination including pathogenic and food spoilage bacteria. The antibiotic resistance represents an additional risk for food industry, and it is worthy of special attention as spices are important food additives. During our work, we examined the microbiological quality of 50 different spices with cultivation methods on diverse selective media. The identification of the most representative bacteria was carried out using 16S rDNA gene sequence analysis. Antibiotic resistance profiling of twelve identified Bacillus species (B. subtilis subsp. stercoris BCFK, B. licheniformis BCLS, B. siamensis SZBC, B. zhangzhouensis BCTA, B. altitudinis SALKÖ, B. velezensis CVBC, B. cereus SALÖB isolate, B. tequilensis KOPS, B. filamentosus BMBC, B. subtilis subsp. subtilis PRBC2, B. safensis BMPS, and B. mojavensis BCFK2 isolate) was performed using the standard disk-diffusion method against 32 antibiotics. The study showed that the majority resistance was obtained against penicillin G (100%), oxacillin (91.67%), amoxyclav (91.67%), rifampicin (75%), and azithromycin (75%). Our findings suggest that spices harbor multidrug-resistant bacteria. | 2021 | 34401102 |
| 5390 | 3 | 0.8849 | Presence of erythromycin and tetracycline resistance genes in lactic acid bacteria from fermented foods of Indian origin. Lactic acid bacteria (LAB) resistant to erythromycin were isolated from different food samples on selective media. The isolates were identified as Enterococcus durans, Enterococcus faecium, Enterococcus lactis, Enterococcus casseliflavus, Lactobacillus salivarius, Lactobacillus reuteri, Lactobacillus plantarum, Lactobacillus fermentum, Pediococcus pentosaceus and Leuconostoc mesenteroides. Of the total 60 isolates, 88 % harbored the ermB gene. The efflux gene msrA was identified in E. faecium, E. durans, E. lactis, E. casseliflavus, P. pentosaceus and L. fermentum. Further analysis of the msrA gene by sequencing suggested its homology to msrC. Resistance to tetracycline due to the genes tetM, tetW, tetO, tetK and tetL, alone or in combination, were identified in Lactobacillus species. The tetracycline efflux genes tetK and tetL occurred in P. pentosaceus and Enterococcus species. Since it appeared that LAB had acquired these genes, fermented foods may be a source of antibiotic resistance. | 2012 | 22644346 |
| 5387 | 4 | 0.8848 | Assessment of antibiotic susceptibility within lactic acid bacteria strains isolated from wine. Susceptibility to 12 antibiotics was tested in 75 unrelated lactic acid bacteria strains of wine origin of the following species: 38 Lactobacillus plantarum, 3 Lactobacillus hilgardii, 2 Lactobacillus paracasei, 1 Lactobacillus sp, 21 Oenococcus oeni, 4 Pediococcus pentosaceus, 2 Pediococcus parvulus, 1 Pediococcus acidilactici, and 3 Leuconostoc mesenteroides. The Minimal Inhibitory Concentrations of the different antibiotics that inhibited 50% of the strains of the Lactobacillus, Leuconostoc and Pediococcus genera were, respectively, the following ones: penicillin (2, < or =0.5, and < or =0.5 microg/ml), erythromycin (< or =0.5 microg/ml), chloramphenicol (4 microg/ml), ciprofloxacin (64, 8, and 128 microg/ml), vancomycin (> or =128 microg/ml), tetracycline (8, 2, and 8 microg/ml), streptomycin (256, 32, and 512 microg/ml), gentamicin (64, 4, and 128 microg/ml), kanamycin (256, 64, and 512 microg/ml), sulfamethoxazole (> or =1024 microg/ml), and trimethoprim (16 microg/ml). All 21 O. oeni showed susceptibility to erythromycin, tetracycline, rifampicin and chloramphenicol, and exhibited resistance to aminoglycosides, vancomycin, sulfamethoxazole and trimethoprim, that could represent intrinsic resistance. Differences were observed among the O. oeni strains with respect to penicillin or ciprofloxacin susceptibility. Antibiotic resistance genes were studied by PCR and sequencing, and the following genes were detected: erm(B) (one P. acidilactici), tet(M) (one L. plantarum), tet(L) (one P. parvulus), aac(6')-aph(2") (four L. plantarum, one P. parvulus, one P. pentosaceus and two O. oeni), ant(6) (one L. plantarum, and two P. parvulus), and aph(3')-IIIa (one L. plantarum and one O. oeni). This is the first time, to our knowledge, that ant(6), aph(3')-IIIa and tet(L) genes are found in Lactobacillus and Pediococcus strains and antimicrobial resistance genes are reported in O. oeni strains. | 2006 | 16876896 |
| 5213 | 5 | 0.8847 | Draft genome sequences of Limosilactobacillus fermentum IJAL 01 335, isolated from a traditional cereal fermented dough. Limosilactobacillus fermentum IJAL 01 335 was isolated from mawè, a spontaneously fermented cereal dough from Benin. The 1.83 Mb draft genome sequence (52.37% GC) comprises 154 contigs, 1,836 coding sequences, and 23 predicted antibiotic resistance genes, providing insights into its genetic features and potential application in food fermentation. | 2025 | 41170963 |
| 3738 | 6 | 0.8845 | In Silico Prediction of Antibiotic Resistance in Mycobacterium ulcerans Agy99 through Whole Genome Sequence Analysis. Buruli ulcer is an emerging infectious disease caused by Mycobacterium ulcerans that has been reported from 33 countries. Antimicrobial agents either alone or in combination with surgery have been proved to be clinically relevant and therapeutic strategies have been deduced mainly from the empirical experience. The genome sequences of M. ulcerans strain AGY99, M. ulcerans ecovar liflandii, and three Mycobacterium marinum strains were analyzed to predict resistance in these bacteria. Fourteen putative antibiotic resistance genes from different antibiotics classes were predicted in M. ulcerans and mutation in katG (R431G) and pncA (T47A, V125I) genes were detected, that confer resistance to isoniazid and pyrazinamide, respectively. No mutations were detected in rpoB, gyrA, gyrB, rpsL, rrs, emb, ethA, 23S ribosomal RNA genes and promoter region of inhA and ahpC genes associated with resistance. Our results reemphasize the usefulness of in silico analysis for the prediction of antibiotic resistance in fastidious bacteria. | 2017 | 28749770 |
| 5448 | 7 | 0.8844 | Virulence gene profiles, biofilm formation, and antimicrobial resistance of Vibrio cholerae non-O1/non-O139 bacteria isolated from West Bengal, India. Vibrio cholerae is the causative agent of acute dehydrating diarrhoeal disease cholera. Among 71 V. cholerae non-O1/non-O139 isolates, all yielded negative results for ctxA, ctxB and tcpA genes in PCR assay. Few strains were positive for stn (28.38%), and ompU (31.08%) genes. While all isolates were negative for ace gene, only two were positive for zot gene. All strains expressed toxR and toxT genes. It was also found that all isolates were slime-producer and these were capable of forming moderate to high biofilm. Biofilm formation was controlled positively by the transcriptional regulators VpsR and VpsT and was regulated negatively by HapR, as well as CRP regulatory complex. These isolates were resistant to ampicillin, furazolidone, doxycycline, vancomycin, erythromycin, while these were susceptible to ciprofloxacin, gentamycin, kanamycin, polymixin B, norfloxacin, chloramphenicol, sulphamethoxazole-trimethoprim, tetracycline, nalidixic acid, and streptomycin. Indeed, 69.01% isolates were resistant to multiple antibiotics (MAR: resistance to 3 or more antibiotics). Treatment protocols for cholera patients should be based on local antibiogram data. | 2018 | 30582054 |
| 1261 | 8 | 0.8839 | Antibiotic Resistance Genes, Virulence Factors, and Biofilm Formation in Coagulase-Negative Staphylococcus spp. Isolates from European Hakes (Merluccius merluccius, L.) Caught in the Northeast Atlantic Ocean. The indiscriminate use of antibiotics has contributed to the dissemination of multiresistant bacteria, which represents a public health concern. The aim of this work was to characterize 27 coagulase-negative staphylococci (CoNS) isolated from eight wild Northeast Atlantic hakes (Merluccius merluccius, L.) and taxonomically identified as Staphylococcus epidermidis (n = 16), Staphylococcus saprophyticus (n = 4), Staphylococcus hominis (n = 3), Staphylococcus pasteuri (n = 2), Staphylococcus edaphicus (n = 1), and Staphylococcus capitis (n = 1). Biofilm formation was evaluated with a microtiter assay, antibiotic susceptibility testing was performed using the disk diffusion method, and antibiotic resistance and virulence determinants were detected by PCR. Our results showed that all staphylococci produced biofilms and that 92.6% of the isolates were resistant to at least one antibiotic, mainly penicillin (88.8%), fusidic acid (40.7%), and erythromycin (37%). The penicillin resistance gene (blaZ) was detected in 66.6% (18) of the isolates, of which 10 also carried resistance genes to macrolides and lincosamides (mphC, msr(A/B), lnuA, or vgaA), 4 to fusidic acid (fusB), and 3 to trimethoprim-sulfamethoxazole (dfrA). At least one virulence gene (scn, hla, SCCmecIII, and/or SCCmecV) was detected in 48% of the isolates. This study suggests that wild European hake destined for human consumption could act as a vector of CoNS carrying antibiotic resistance genes and/or virulence factors. | 2023 | 38133330 |
| 1260 | 9 | 0.8839 | Isolation, Identification, and Antimicrobial Susceptibilities of Bacteria from the Conjunctival Sacs of Dogs with Bacterial Conjunctivitis in Different Regions of Wuhan, China. In order to investigate the bacterial species present in the conjunctival sacs of dogs with bacterial conjunctivitis in Wuhan (Hongshan District, Wuchang District, Jiangxia District, and Huangpi District) and their resistance to aminoglycoside antibiotics, samples of conjunctival sac secretions were collected from 56 dogs with bacterial conjunctivitis in various regions of Wuhan. Drug susceptibility testing for aminoglycoside antibiotics was performed on the most commonly isolated gram-positive and gram-negative bacteria. The expression of two aminoglycoside modifying enzyme genes, aacA-aphD and aac (6')-Ib, and three 16S rRNA methyltransferase genes, rmtB, rmtE and npmA, were analyzed by PCR. The results showed that a total of 123 bacterial strains were cultured from 56 conjunctival sac secretion samples, with Staphylococcus being the most commonly isolated species, followed by Escherichia. Among them, 14 strains of Staphylococcus pseudointermedius were not resistant to tobramycin, amikacin, gentamicin or neomycin, but the resistance rates to streptomycin and kanamycin were 35.71% and 42.86%, respectively. Among them, 14 Escherichia coli strains were not resistant to tobramycin and gentamicin, but they showed high resistance rates to neomycin and kanamycin (both at 50%). The detection rate of the aacA-aphD gene in Staphylococcus pseudointermedius strains was 100%. The detection rates of the rmtB gene and rmtE gene in Escherichia coli were 85.71% and 28.57%, respectively, while the aac(6')-Ib gene and npmA gene were not detected. | 2025 | 39852896 |
| 5395 | 10 | 0.8838 | Assessment of Antibiotic Susceptibility within Lactic Acid Bacteria and Coagulase-Negative Staphylococci Isolated from Hunan Smoked Pork, a Naturally Fermented Meat Product in China. The aim of this study was to evaluate the antibiotic susceptibility of lactic acid bacteria (LAB) and coagulase-negative staphylococci (CNS) strains isolated from naturally fermented smoked pork produced in Hunan, China. A total of 48 strains were isolated by selective medium and identified at the species level by 16S rRNA gene sequencing as follows: Staphylococcus carnosus (23), Lactobacillus plantarum (12), Lactobacillus brevis (10), Lactobacillus sakei (1), Weissella confusa (1), and Weissella cibaria (1). All strains were typed by RAPD-PCR, and their susceptibility to 15 antibiotics was determined and expressed as the minimum inhibitory concentration (MIC) using agar dilution method. High resistance to penicillin G, streptomycin, gentamycin, vancomycin, chloramphenicol, norfloxacin, ciprofloxacin, kanamycin, and neomycin was found among the isolates. All the strains were sensitive to ampicillin, while the susceptibility to tetracycline, oxytetracycline, erythromycin, lincomycin, and roxithromycin varied. The presence of relevant resistance genes was investigated by PCR and sequencing, with the following genes detected: str(A), str(B), tet(O), tet(M), ere(A), and catA. Eleven strains, including 3 S. carnosus, 6 L. plantarum, and 2 L. brevis, harbored more than 3 antibiotic resistance genes. Overall, multiple antibiotic resistance patterns were widely observed in LAB and S. carnosus strains isolated from Hunan smoked pork. Risk assessment should be carried out with regard to the safe use of LAB and CNS in food production. PRACTICAL APPLICATION: We evaluated the antibiotic resistance of lactic acid bacteria and coagulase-negative staphylococci strains isolated from Chinese naturally fermented smoked pork. Our results may provide important data on establishing breakpoint standards for LAB and CNS and evaluating the safety risk of these strains for commercial use. | 2018 | 29786847 |
| 5386 | 11 | 0.8838 | Antibiotic resistance of lactic acid bacteria isolated from Chinese yogurts. The aim of this study was to evaluate the susceptibility of 43 strains of lactic acid bacteria, isolated from Chinese yogurts made in different geographical areas, to 11 antibiotics (ampicillin, penicillin G, roxithromycin, chloramphenicol, tetracycline, chlortetracycline, lincomycin, kanamycin, streptomycin, neomycin, and gentamycin). The 43 isolates (18 Lactobacillus bulgaricus and 25 Streptococcus thermophilus) were identified at species level and were typed by random amplified polymorphic DNA analysis. Thirty-five genotypically different strains were detected and their antimicrobial resistance to 11 antibiotics was determined using the agar dilution method. Widespread resistance to ampicillin, chloramphenicol, chlortetracycline, tetracyclines, lincomycin, streptomycin, neomycin, and gentamycin was found among the 35 strains tested. All of the Strep. thermophilus strains tested were susceptible to penicillin G and roxithromycin, whereas 23.5 and 64.7% of Lb. bulgaricus strains, respectively, were resistant. All of the Strep. thermophilus and Lb. bulgaricus strains were found to be resistant to kanamycin. The presence of the corresponding resistance genes in the resistant isolates was investigated through PCR, with the following genes detected: tet(M) in 1 Lb. bulgaricus and 2 Strep. thermophilus isolates, ant(6) in 2 Lb. bulgaricus and 2 Strep. thermophilus isolates, and aph(3')-IIIa in 5 Lb. bulgaricus and 2 Strep. thermophilus isolates. The main threat associated with these bacteria is that they may transfer resistance genes to pathogenic bacteria, which has been a major cause of concern to human and animal health. To our knowledge, the aph(3')-IIIa and ant(6) genes were found in Lb. bulgaricus and Strep. thermophilus for the first time. Further investigations are required to analyze whether the genes identified in Lb. bulgaricus and Strep. thermophilus isolates might be horizontally transferred to other species. | 2012 | 22916881 |
| 5396 | 12 | 0.8837 | Antibiotic Resistance of Coagulase-Negative Staphylococci and Lactic Acid Bacteria Isolated from Naturally Fermented Chinese Cured Beef. This study provided phenotypic and molecular analysis of the antibiotic resistance within coagulase-negative staphylococci and lactic acid bacteria isolated from naturally fermented Chinese cured beef. A total of 49 strains were isolated by selective medium and identified at the species level by 16S rRNA gene sequencing as follows: Staphylococcus carnosus (37), Lactobacillus plantarum (6), Weissella confusa (4), Lactobacillus sakei (1), and Weissella cibaria (1). All strains were typed by random amplified polymorphic DNA fingerprinting, and their antibiotic resistances profiles to 15 antibiotics were determined as the MIC by using the agar dilution method. All the tested strains were sensitive to ampicillin, and most of them were also sensitive to penicillin, gentamycin, neomycin, norfloxacin, and ciprofloxacin with low MICs. High resistance to streptomycin, vancomycin, erythromycin, roxithromycin, lincomycin, and kanamycin was widely observed, while the resistant levels to tetracycline, oxytetracycline, and chloramphenicol varied. The presence of corresponding resistance genes in resistant isolates was investigated by PCR, with the following genes detected: tet(M) gene in 9 S. carnosus strains and 1 W. confusa strain; erm(F) gene in 10 S. carnosus strains; ere(A) gene in 6 S. carnosus strains; ere(A) gene in 4 S. carnosus strains and 1 L. plantarum strain; and str(A) gene and str(B) gene in 3 S. carnosus strains. The results indicated that multiple antibiotic resistances were common in coagulase-negative staphylococci and lactic acid bacteria strains isolated from naturally fermented Chinese cured beef. Safety analysis and risk assessment should be performed for application in meat products. | 2018 | 30485765 |
| 5388 | 13 | 0.8837 | Molecular identification and antibiotic resistance of bacteriocinogenic lactic acid bacteria isolated from table olives. In the present study, lactic acid bacteria were isolated from table olive in Morocco. Random Amplified Polymorphic DNA fingerprinting with (GTG)'(5) primer revealed a remarquable variability within isolates. According to the molecular identification, Enterococcus faecium was the most dominant species isolated with 32 strains (84.21%), followed by 4 strains of Weissella paramesenteroides (10.52%), 1 strain of Leuconostoc mesenteroides (2.63%) and Lactobacillus plantarum (2.63%). All of the strains that were identified showed occurrence of more than one bacteriocin-encoding gene. Based on the results obtained, L. plantarum 11 showed a mosaic of loci coding for nine bacteriocins (pln A, pln D, pln K, pln G, pln B, pln C, pln N, pln J, ent P). A phenotypic and genotypic antibiotic resistance was also examined. L. plantarum 11, L. mesenteroides 62, W. paramesenteroides 9 and W. paramesenteroides 36 as well as all the strains of E. faecium were susceptible to ampicillin, clindamycin and teicoplanin; however, isolates showed a resistance profile against tetracycline and erythromycin. Except E. faecium 114, E. faecium 130 and L. plantarum 11, no antibiotic resistance genes were detected in all of the strains, which might be due to resistances resulting from non-transferable or non-acquired resistance determinants (intrinsic mechanism). | 2021 | 32995979 |
| 5389 | 14 | 0.8836 | Identification and characterization of potential probiotic lactic acid bacteria isolated from pig feces at various production stages. Lactic acid bacteria (LAB) were isolated, identified, and characterized from pig feces at various growth stages and feed rations in order to be used as probiotic feed additives. Lactic acid bacteria numbers ranged from 7.10 ± 1.50 to 9.40 log CFUs/g for growing and lactating pigs, respectively. Isolates (n = 230) were identified by (GTG)5-polymerase chain reaction and partial sequence analysis of 16S rRNA. Major LAB populations were Limosilactobacillus reuteri (49.2%), Pediococcus pentosaceus (20%), Lactobacillus amylovorus (11.4%), and L. johnsonii (8.7%). In-vitro assays were performed, including surface characterization and tolerance to acid and bile salts. Several lactobacilli exhibited hydrophobic and aggregative characteristics and were able to withstand gastrointestinal tract conditions. In addition, lactobacilli showed starch- and phytate-degrading ability, as well as antagonistic activity against Gram-negative pathogens and the production of bacteriocin-like inhibitory substances. When resistance or susceptibility to antibiotics was evaluated, high phenotypic resistance to ampicillin, gentamicin, kanamycin, streptomycin, and tetracycline and susceptibility towards clindamycin and chloramphenicol was observed in the assayed LAB. Genotypic characterization showed that 5 out of 15 resistance genes were identified in lactobacilli; their presence did not correlate with phenotypic traits. Genes erm(B), strA, strB, and aadE conferring resistance to erythromycin and streptomycin were reported among all lactobacilli, whereas tet(M) gene was harbored by L. reuteri and L. amylovorus strains. Based on these results, 6 probiotic LAB strains (L. reuteri F207R/G9R/B66R, L. amylovorus G636T/S244T, and L. johnsonii S92R) can be selected to explore their potential as direct feed additives to promote swine health and replace antibiotics. | 2023 | 37020571 |
| 1342 | 15 | 0.8834 | Prevalence, Toxin Genes, and Antibiotic Resistance Profiles of Bacillus cereus Isolates from Spices in Antalya and Isparta Provinces in Türkiye. Bacillus cereus is a pathogenic bacterium commonly found in nature and can produce toxins that cause food poisoning. This study aimed to detect the prevalence of B. cereus group bacteria in 50 unpackaged and 20 packaged spice samples frequently used as flavoring in Turkish cuisine, as well as investigate the presence of toxin genes and antibiotic resistance in the isolates. A total of 48 B. cereus group bacteria were isolated from 27 of 70 (38.57%) spice samples. The prevalence of B. cereus group bacteria in packaged (25%, 5/20) and unpackaged (44%, 22/50) spice samples did not differ significantly (P ˃ 0.05). All B. cereus group isolates were identified as B. cereus sensu stricto (B. cereus) using molecular methods. The hemolytic activity tests revealed that the most strains (44/48, 91.67%) are β-hemolytic. The distributions of toxin genes in isolates were investigated by PCR. It was determined that all isolates were identified to have 2-8 toxin genes, except B. cereus SBC3. The three most common toxin genes were found to be nheA (47/48, 97.92%), nheB (46/48, 95.83%), and entFM (46/48, 95.83%). All B. cereus isolates were susceptible to linezolid and vancomycin, while 35.42% (17/48) showed resistance to erythromycin. Multi-drug resistance (MDR) was detected in 8.3% (4/48) of B. cereus isolates, while 33.33% of the isolates showed multiple antibiotic resistance (MAR) index values higher than 0.2. The findings indicate that B. cereus may pose a health risk in packaged and unpackaged spices if present in high quantities. Therefore, the presence of B. cereus strains in both packaged and unpackaged spices should be monitored regarding consumer health and product safety. | 2023 | 38031610 |
| 531 | 16 | 0.8832 | 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 |
| 5384 | 17 | 0.8832 | Characterization of drug resistance and virulotypes of Salmonella strains isolated from food and humans. The virulence of bacteria can be evaluated through both phenotypic and molecular assays. We applied these techniques to 114 strains of Salmonella enterica subsp. enterica collected from July 2010 to June 2012. Salmonella strains were of human origin (71/114) or isolated from food (43/114). The strain set included only the three predominant Salmonella serovars isolated in Italy from humans (S. Enteritidis, S. Typhimurium, S. 4,[5],12:i:-). These strains were screened via polymerase chain reaction for 12 virulence factors (gipA, gtgB, sopE, sspH1, sspH2, sodC1, gtgE, spvC, pefA, mig5, rck, srgA), while antimicrobial sensitivity was evaluated through the Kirby-Bauer assay. Fifty-nine different virulence profiles were highlighted; the genes showing the highest homology were those related to the presence of prophages (gipA, gtgB, sopE, sspH1, sspH2, sodC1, gtgE), while the genes related to the presence of plasmids were less frequently detected (spvC, pefA, mig5, rck, srgA). The Salmonella serovars Typhimurium and 4,[5],12:i:- were closely related in terms of both virulotyping and antibiotic resistance. S. Enteritidis showed higher antibiotic sensitivity and a higher prevalence of genes related to plasmids. | 2013 | 24102078 |
| 105 | 18 | 0.8832 | Resistance of the cholera vaccine candidate IEM108 against CTXPhi infection. The cholera toxin (CT) genes ctxAB are carried on a lysogenic phage of Vibrio cholerae, CTXPhi, which can transfer ctxAB between toxigenic and nontoxigenic strains of bacteria. This transfer may pose a problem when live oral cholera vaccine is given to people in epidemic areas, because the toxin genes can be reacquired by the vaccine strains. To address this problem, we have constructed a live vaccine candidate, IEM108, which carries an El Tor-derived rstR gene. This gene encodes a repressor and can render bacterial resistance to CTXPhi infection. In this study, we evaluated the resistance of IEM108 against CTXPhi infection by using a CTXPhi marked for chloramphenicol (CAF) resistance and an in vivo model. We found that the cloned rstR gene rendered IEM108 immune to infection with the marked CTXPhi. In addition, the infection rate of IEM108 was even lower than that of the native CTXPhi-positive strain. These results suggest that the vaccine candidate IEM108 is resistant to infection by CTXPhi. | 2006 | 16343705 |
| 5403 | 19 | 0.8831 | Distribution of antimicrobial-resistant lactic acid bacteria in natural cheese in Japan. To determine and compare the extent of contamination caused by antimicrobial-resistant lactic acid bacteria (LAB) in imported and domestic natural cheeses on the Japanese market, LAB were isolated using deMan, Rogosa and Sharpe (MRS) agar and MRS agar supplemented with six antimicrobials. From 38 imported and 24 Japanese cheeses, 409 LAB isolates were obtained and their antimicrobial resistance was tested. The percentage of LAB resistant to dihydrostreptomycin, erythromycin, and/or oxytetracycline isolated from imported cheeses (42.1%) was significantly higher than that of LAB resistant to dihydrostreptomycin or oxytetracycline from cheeses produced in Japan (16.7%; P=0.04). Antimicrobial resistance genes were detected in Enterococcus faecalis (tetL, tetM, and ermB; tetL and ermB; tetM) E. faecium (tetM), Lactococcus lactis (tetS), Lactobacillus (Lb.), casei/paracasei (tetM or tetW), and Lb. rhamnosus (ermB) isolated from seven imported cheeses. Moreover, these E. faecalis isolates were able to transfer antimicrobial resistance gene(s). Although antimicrobial resistance genes were not detected in any LAB isolates from Japanese cheeses, Lb. casei/paracasei and Lb. coryniformis isolates from a Japanese farm-made cheese were resistant to oxytetracycline (minimal inhibitory concentration [MIC], 32 µg/mL). Leuconostoc isolates from three Japanese farm-made cheeses were also resistant to dihydrostreptomycin (MIC, 32 to >512 µg/mL). In conclusion, the present study demonstrated contamination with antimicrobial-resistant LAB in imported and Japanese farm-made cheeses on the Japanese market, but not in Japanese commercial cheeses. | 2013 | 23930694 |