I1 - Word Related Documents




#
Rank
Similarity
Title + Abs.
Year
PMID
012345
123600.9821Molecular characterization of antimicrobial resistance in Gram-negative bacteria isolated from bovine mastitis in Egypt. The aim of this study was to characterize the genetic basis of multidrug resistance in Gram-negative bacteria isolated from bovine mastitis cases in Egypt. Multidrug resistance phenotypes were found in 34 of 112 (30.4%) Gram-negative bacterial isolates, which harbored at least one antimicrobial resistance gene. The most prevalent multidrug-resistant (MDR) species were Enterobacter cloacae (8 isolates, 7.1%), Klebsiella pneumoniae (7 isolates, 6.3%), Klebsiella oxytoca (7 isolates, 6.3%), Escherichia coli (5 isolates, 4.5%), and Citrobacter freundii (3 isolates, 2.7%). The most commonly observed resistance phenotypes were against ampicillin (97.0%), streptomycin (94.1%), tetracycline (91.2%), trimethoprim-sulfamethoxazole (88.2%), nalidixic acid (85.3%), and chloramphenicol (76.5%). Class 1 integrons were detected in 28 (25.0%) isolates. The gene cassettes within class 1 integrons included those encoding resistance to trimethoprim (dfrA1, dfrA5, dfrA7, dfrA12, dfrA15, dfrA17, and dfrA25), aminoglycosides (aadA1, aadA2, aadA5, aadA7, aadA12, aadA22, and aac(3)-Id), chloramphenicol (cmlA), erythromycin (ereA2), and rifampicin (arr-3). Class 2 integrons were identified in 6 isolates (5.4%) with three different profiles. Furthermore, the β-lactamase encoding genes, bla(TEM), bla(SHV), bla(CTX-M), and bla(OXA), the plasmid-mediated quinolone resistance genes, qnr and aac(6)-Ib-cr, and the florfenicol resistance gene, floR, were also identified. To the best of our knowledge, the results identified class 2 integrons, qnr and aac(6)-Ib-cr from cases of mastitis for the first time. This is the first report of molecular characterization for antimicrobial resistance in Gram-negative bacteria isolated from bovine mastitis in Africa.201121338385
123310.9820Prevalence, Antibiogram, and Resistance Profile of Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolates from Pig Farms in Luzon, Philippines. This cross-sectional study was conducted to determine the prevalence, antibiogram, and resistance profile of extended-spectrum β-lactamase-producing Escherichia coli (ESBL-EC) isolates from healthy pigs and pig farms in Luzon, Philippines. A total of 162 rectal samples from healthy finisher and breeder pigs and boot swab samples from pig houses were collected from 54 randomly selected pig farms. Bacteria were isolated and screened using MacConkey agar plate supplemented with 1 mg/L cefotaxime. Identification of bacteria and antimicrobial susceptibility test were carried out through Vitek(®) 2 and combined disk test. PCR amplifications were carried out in all isolates targeting bla(CTX-M) and its five major groupings, bla(TEM), and bla(SHV). The farm prevalence of ESBL-EC was 57.41% (95% confidence interval [CI] = 43.21-70.77). A total of 48 (29.63%) ESBL-EC isolates were isolated from samples that showed 14 different phenotypic multidrug resistance patterns. The prevalence of bla(CTX-M) gene was 91.67% (95% CI = 80.02-97.68). All major bla(CTX-M-groups) except bla(CTX-M-25group) were detected. The bla(CTX-M-1) was the most prevalent bla(CTX-M) gene, 75.0% (95% CI = 60.40-86.36). The prevalence of bla(TEM) and bla(SHV) genes was 91.67% (95% CI = 80.02-97.68) and 60.42% (95% CI = 45.27-74.23), respectively. Coexistence of different bla(CTX-M), bla(TEM), and bla(SHV) genes was observed in 44 isolates with 20 different genotypic patterns. High prevalence, diverse antibiogram profile, and genotypic resistance pattern of ESBL-EC isolates from healthy pigs and pig farms were observed in this study that could result in possible transmission to farm workers, susceptible bacteria, and the environment.202031532307
122620.9814Multi-drug resistant gram-negative enteric bacteria isolated from flies at Chengdu Airport, China. We collected flies from Chengdu Shuangliu International Airport to examine for the presence of bacteria and to determine the sensitivity patterns of those bacteria. A total of 1,228 flies were collected from 6 sites around Chengdu Shuangliu International Airport from April to September 2011. The predominant species was Chrysomya megacephala (n=276, 22.5%). Antimicrobial-resistant gram-negative enteric bacteria (n=48) were isolated from flies using MacConkey agar supplemented with cephalothin (20 microg/ml). These were identified as Escherichia coli (n=37), Klebsiella pneumoniae (n=6), Pseudomonas aeruginosa (n=3) and Aeromonas hydrophila (n=2). All isolated bacteria were tested for resistance to 21 commonly used antimicrobials: amoxicillin (100%), ticarcillin (100%), cephalothin (100%), cefuroxime (100%), ceftazidime 1 (93.8%), piperacillin (93.8%), cefotaxime (89.6%), ticarcillin-clavulanate (81.3%), trimethoprim-sulfamethoxazole (62.5%), ciprofloxacin (54.2%), gentamicin (45.8%), cefepime (39.6%), tobramycin (39.6%), ceftazidime (22.9%), cefoxitin (16.7%), amikacin (16.7%), netilmicin (14.6%), amoxicillin-clavulanate (6.3%) and piperacillin-tazobactam (2.1%). No resistance to meropenem or imipenem was observed. Antibiotic resistance genes among the isolated bacteria were analyzed for by polymerase chain reaction. Thirty of the 48 bacteria with resistance (62.5%) possessed the blaTEM gene.201324450236
123230.9812Monitoring of Non-β-Lactam Antibiotic Resistance-Associated Genes in ESBL Producing Enterobacterales Isolates. Genetic context of extended spectrum β-Lactamase (ESBL) producing Enterobacterales and its association with plasmid mediated quinolone resistance (PMQR), aminoglycoside modifying enzymes (AME) and Trimethoprim/Sulfamethoxazole (TMP-SMX) resistance is little known from North India. Therefore, the current study was aimed to investigate the frequency of Non-β-Lactam antibiotic resistance associated genes in extended spectrum β-Lactamase producing Enterobacterales. For this study, Non-Duplicate phenotypically confirmed ESBL producing Enterobacterales isolates (N = 186) were analyzed for ESBLs, PMQRs, AMEs and TMP-SMX resistance genes using polymerase chain reaction (PCR). PCR detected presence of PMQR genes in 81.29% (N = 139) of ESBL isolates (N = 171), AME genes in 60.82% and TMP-SMX resistance genes in 63.74% of the isolates. Molecular characterization of ESBL producing Enterobacterales showed 84.79% bla(TEM) followed by 73.68% bla(CTX-M), 43.86% bla(SHV), 19.88% bla(PER) and 9.94% bla(VEB), respectively. Analysis of PMQR genes revealed 77.7% aac(6')-lb-cr the most commonly detected gene followed by 67.63% oqxB, 62.59% oqxA, 43.17% qnrB, 19.42% qnrD, 18.7% qnrS, 9.35% qnrA, 3.6% qepA and 2.88% qnrC, respectively. Analysis of AMEs gene profile demonstrated 81.73% aac(6')-Ib, the most frequently encountered gene followed by 46.15% aph(3')-Ia, 44.23% ant(3")-Ia, respectively. A 100% prevalence of sul1, followed by dfrA (54.63%) and sul2 (15.74%) was observed. In summary, prevalence of ESBL-Producing genes (particularly bla(TEM) and bla(CTX-M)) along with PMQR, AMEs, and TMP-SMX resistant genes may potentially aid in the transfer of antimicrobial resistance among these strains.202033317078
138840.9811Snapshot Study of Whole Genome Sequences of Escherichia coli from Healthy Companion Animals, Livestock, Wildlife, Humans and Food in Italy. Animals, humans and food are all interconnected sources of antimicrobial resistance (AMR), allowing extensive and rapid exchange of AMR bacteria and genes. Whole genome sequencing (WGS) was used to characterize 279 Escherichia coli isolates obtained from animals (livestock, companion animals, wildlife), food and humans in Italy. E. coli predominantly belonged to commensal phylogroups B1 (46.6%) and A (29%) using the original Clermont criteria. One hundred and thirty-six sequence types (STs) were observed, including different pandemic (ST69, ST95, ST131) and emerging (ST10, ST23, ST58, ST117, ST405, ST648) extraintestinal pathogenic Escherichia coli (ExPEC) lineages. Eight antimicrobial resistance genes (ARGs) and five chromosomal mutations conferring resistance to highest priority critically important antimicrobials (HP-CIAs) were identified (qnrS1, qnrB19, mcr-1, bla(CTX-M1,15,55), bla(CMY-2), gyrA/parC/parE, ampC and pmrB). Twenty-two class 1 integron arrangements in 34 strains were characterized and 11 ARGs were designated as intI1 related gene cassettes (aadA1, aadA2, aadA5, aad23, ant2_Ia, dfrA1, dfrA7, dfrA14, dfrA12, dfrA17, cmlA1). Notably, most intI1 positive strains belonged to rabbit (38%) and poultry (24%) sources. Three rabbit samples carried the mcr-1 colistin resistance gene in association with IS6 family insertion elements. Poultry meat harbored some of the most prominent ExPEC STs, including ST131, ST69, ST10, ST23, and ST117. Wildlife showed a high average number of virulence-associated genes (VAGs) (mean = 10), mostly associated with an ExPEC pathotype and some predominant ExPEC lineages (ST23, ST117, ST648) were identified.202033172096
123550.9810Characterization of integrons and antimicrobial resistance genes in clinical isolates of Gram-negative bacteria from Palestinian hospitals. Sixty Gram-negative bacterial isolates were collected from Palestinian hospitals in 2006. Thirty-two (53.3%) isolates showed multidrug resistance phenotypes. PCR and DNA sequencing were used to characterize integrons and antimicrobial resistance genes. PCR screening showed that 19 (31.7%) and five (8.3%) isolates were positive for class 1 and class 2 integrons, respectively. DNA-sequencing results for the captured antimicrobial resistance gene cassettes within class 1 integrons identified the following genes: dihydrofolate reductases, dfrA1, dfrA5, dfrA7, dfrA12, dfrA17 and dfrA25; aminoglycoside adenyltransferases, aadA1, aadA2, aadA5, aadA12 and aadB; aminoglycoside acetyltransferase, aac(6')-Ib; and chloramphenicol resistance gene, cmlA1. ESBL were identified in 25 (41.7%) isolates. The identified ESBL were bla(CTX-M-15), bla(CTX-M-56), bla(OXA-1), bla(SHV-1), bla(SHV-12), bla(SHV-32) and bla(TEM-1) genes. Moreover, we characterized the plasmid-mediated quinolone resistance genes, aac(6')-Ib-cr and qnrB2, which were detected in seven (11.7%) and two (3.3%) isolates, respectively. In this study various types of antibiotic resistance genes have been identified in Gram-negative bacteria from Palestinian hospitals, many of which are reported in the Middle East area for the first time.200919903259
108860.9810Detection and Molecular Characterization of Escherichia coli Strains Producers of Extended-Spectrum and CMY-2 Type Beta-Lactamases, Isolated from Turtles in Mexico. Multidrug-resistant bacteria are a growing problem in different environments and hosts, but scarce information exists about their prevalence in reptiles. The aim of this study was to analyze the resistance mechanisms, molecular typing, and plasmid content of cefotaxime-resistant (CTX(R)) Escherichia coli isolates recovered from cloacal samples of 71 turtles sheltered in a herpetarium in Mexico. CTX(R)-E. coli were recovered in 11 of 71 samples (15.5%), and one isolate/sample was characterized. Extended-spectrum β-lactamase (ESBL)-producing E. coli isolates were detected in four samples (5.6%): two strains carried the blaCTX-M-2 gene (phylogroup D and ST2732) and two contained the blaCTX-M-15 gene (phylogroup B1 and lineages ST58 and ST156). The blaCMY-2 gene was detected by PCR in E. coli isolates of eight samples (9.8%) (one of them also carried blaCTX-M-2); these isolates were distributed into phylogroups A (n = 1), B1 (n = 6), and D (n = 1) and typed as ST155, ST156, ST2329, and ST2732. Plasmid-mediated quinolone resistance (PMQR) genes were detected in five isolates [aac(6')Ib-cr, qnrA, qnrB19, and oqxB]. From three to five replicon plasmids were detected among the strains, being IncFIB, IncI1, IncFrep, and IncK the most prevalent. ESBL or pAmpC genes were transferred by conjugation in four strains, and the blaCTX-M-15 and blaCMY-2 genes were localized in IncFIB or IncI1 plasmids by Southern blot hybridization assays. Class 1 and/or class 2 integrons were detected in eight strains with six different structures of gene cassette arrays. Nine pulsed-field gel electrophoresis patterns were found among the 11 studied strains. To our knowledge, this is the first detection of ESBL, CMY-2, PMQR, and mobile determinants of antimicrobial resistance in E. coli of turtle origin, highlighting the potential dissemination of multidrug-resistant bacteria from these animals to other environments and hosts, including humans.201627482752
122270.9807Molecular Characterization and the Antimicrobial Resistance Profile of Salmonella spp. Isolated from Ready-to-Eat Foods in Ouagadougou, Burkina Faso. The emergence of antimicrobial-resistantfood-borne bacteria is a great challenge to public health. This study was conducted to characterize and determine the resistance profile of Salmonella strains isolated from foods including sesames, ready-to-eat (RTE) salads, mango juices, and lettuce in Burkina Faso. One hundred and forty-eight biochemically identified Salmonella isolates were characterized by molecular amplification of Salmonella marker invA and spiC, misL, orfL, and pipD virulence genes. After that, all confirmed strains were examined for susceptibility to sixteen antimicrobials, and PCR amplifications were used to identify the following resistance genes: bla (TEM), temA, temB, StrA, aadA, sul1, sul2, tet(A), and tet(B). One hundred and eight isolates were genetically confirmed as Salmonella spp. Virulence genes were observed in 57.4%, 55.6%, 49.1%, and 38% isolates for pipD, SpiC, misL, and orfL, respectively. Isolates have shown moderate resistance to gentamycin (26.8%), ampicillin (22.2%), cefoxitin (19.4%), and nalidixic acid (18.5%). All isolates were sensitive to six antibiotics, including cefotaxime, ceftazidime, aztreonam, imipenem, meropenem, and ciprofloxacin. Among the 66 isolates resistant to at least one antibiotic, 11 (16.7%) were multidrug resistant. The Multiple Antimicrobial Resistance (MAR) index of Salmonella serovars ranged from 0.06 to 0.53. PCR detected 7 resistance genes (tet(A), tet(B), bla (TEM), temB, sul1, sul2, and aadA) in drug-resistant isolates. These findings raise serious concerns because ready-to-eat food in Burkina Faso could serve as a reservoir for spreading antimicrobial resistance genes worldwide.202236406904
111480.9806Third-Generation Cephalosporin Resistance in Intrinsic Colistin-Resistant Enterobacterales Isolated from Retail Meat. Consumption of retail meat contaminated with antimicrobial-resistant (AMR) bacteria is a common route for transmitting clinically relevant resistant bacteria to humans. Here, we investigated the genotypic and phenotypic resistance profiles of intrinsic colistin-resistant (ICR) Enterobacterales isolated from retail meats. ICR Enterobacterales were isolated from 103 samples of chicken, 103 samples of pork, and 104 samples of beef purchased from retail shops in Japan, using colistin-containing media, and their antimicrobial susceptibility was examined. Serratia spp. (440 isolates) showed resistance to cefotaxime (19 isolates, 4.3%), tetracycline (15 isolates, 3.4%), and other antimicrobials (<1%). Hafnia spp. (136) showed resistance to cefotaxime (12 isolates, 8.6%), ceftazidime (four isolates, 2.9%), and tetracycline (two isolates, 1.4%). Proteus spp. (39) showed resistance to chloramphenicol (four isolates, 10.3%), sulfamethoxazole-trimethoprim (four isolates, 10.3%), cefotaxime (two isolates, 5.1%), kanamycin (two isolates, 5.1%), and gentamicin (one isolate, 2.6%). Cedecea spp. (22) were resistant to tetracycline (two isolates, 9.1%) whereas Morganella spp. (11) were resistant to tetracycline (four isolates, 36.4%) and chloramphenicol (one isolate, 9.2%). The resistance genes bla(fonA), bla(ACC), and bla(DHA) were detected in cefotaxime-resistant Serratia spp., Hafnia spp., and Morganella spp. isolates, respectively. This emergence of antimicrobial resistance in ICR Enterobacterales may pose a public health risk.202134943649
122990.9806Detection of multi-drug resistance and AmpC β-lactamase/extended-spectrum β-lactamase genes in bacterial isolates of loggerhead sea turtles (Caretta caretta) from the Mediterranean Sea. Sea turtles are useful sentinels to monitor the dissemination of antimicrobial resistance (AMR) in the marine coastal ecosystems. Forty Gram negative bacteria were isolated from wounds of 52 injured Caretta caretta, living in the Mediterranean Sea. Bacteria were identified using 16S rRNA gene sequencing and tested for susceptibility to 15 antibiotics. In addition, NGS amplicon sequencing was performed to detect the presence of AmpC β-lactamase genes (bla(AmpC)) and extended-spectrum β-lactamase (ESBL) genes (bla(CTX-M,)bla(SHV,)bla(TEM)). Seventy-five percent of the isolates (30/40 isolates) exhibited multidrug resistance (MDR) phenotypes and 32.5% (13/40 isolates) were confirmed to be positive for at least one gene. The variants of ESBLs genes were bla(CTX-M-3,)bla(TEM-236) and bla(SHV-12). Variants of the bla(AmpC)β-lactamase gene i.e., bla(ACT-24), bla(ACT-2), bla(ACT-17), bla(DHA-4) and bla(CMY-37), were also detected. In addition, 4 isolates were found simultaneously harboring CTX and AmpC genes while 2 strains harbored 3 genes (bla(ACT-2+TEM-236+SHV-12), and bla(CTX-M-3+ACT-24+TEM-236)).202133513540
1240100.9805Prevalence and characterization of quinolone resistance and integrons in clinical Gram-negative isolates from Gaza strip, Palestine. BACKGROUND: Gram-negative bacteria with quinolone resistance and extended-spectrum beta-lactamases (ESBLs) present significant treatment challenges. This study evaluated the prevalence and characteristics of quinolone resistance in Gram-negative strains, investigating the relationship between plasmid-mediated quinolone resistance (PMQR), ESBLs, and integrons. METHODS AND RESULTS: We collected 146 Gram-negative isolates from patients in three Palestinian hospitals. For quinolone resistance isolates, the presence and characterization of PMQR, β-lactamase genes and integrons were studied by PCR and sequencing. Out of 146 clinical isolates, 64 (43.8%) were resistant to quinolones, with 62 (97%) being multidrug-resistant (MDR) and 33 (51.5%) ESBL-producers. PMQR-encoding genes were present in 45 (70.3%) isolates, including aac(6')-Ib-cr (26.6%), qnrA (18.8%), qnrS1 (20.8%), and qnrB (6.4%). Bla(CTX-M) genes were detected in 50% (32/64) of isolates, with bla(CTX-M-15) being the most common. Bla(TEM-1), bla(SHV-1) and bla(VIM) genes were found in 13, 6, and 4 isolates, respectively. Class I integrons were found in 31/64 (48%) of isolates, with 14 containing gene cassettes conferring resistance to trimethoprim (dhfr17, dfrA12, dfrA1) and aminoglycosides resistance genes (aadA1, aadA2, aadA5, and aadA6). CONCLUSIONS: This study found a high rate of quinolone resistance, ESBL and integrons in clinical Gram-negative isolates from our hospitals. Urgent measures are crucial, including implementing an antimicrobial resistance surveillance system, to control and continuously monitor the development of antimicrobial resistance.202439066817
1238110.9805Lineages, Virulence Gene Associated and Integrons among Extended Spectrum β-Lactamase (ESBL) and CMY-2 Producing Enterobacteriaceae from Bovine Mastitis, in Tunisia. Extended Spectrum Beta-Lactamase (ESBL) Enterobacteriaceae are becoming widespread enzymes in food-producing animals worldwide. Escherichia coli and Klebseilla pneumoniae are two of the most significant pathogens causing mastitis. Our study focused on the characterization of the genetic support of ESBL/pAmpC and antibiotic resistance mechanisms in cefotaxime-resistant (CTXR) and susceptible (CTXS) Enterobacteriaceae isolates, recovered from bovine mastitis in Tunisia, as well as the analyses of their clonal lineage and virulence-associated genes. The study was carried out on 17 ESBL/pAmpC E. coli and K. pneumoniae and 50 CTXS E. coli. Detection of resistance genes and clonal diversity was performed by PCR amplification and sequencing. The following β-lactamase genes were detected: blaCTX-M-15 (n = 6), blaCTX-M-15 + blaOXA-1 (2), bla CTX-M-15 + blaOXA-1 + blaTEM-1b (2), blaCTX-M-15 + blaTEM-1b (4), blaCMY-2 (3). The MLST showed the following STs: ST405 (n = 4 strains); ST58 (n = 3); ST155 (n = 3); ST471 (n = 2); and ST101 (n = 2). ST399 (n = 1) and ST617 (n = 1) were identified in p(AmpC) E. coli producer strains. The phylogroups A and B1 were the most detected ones, followed by the pathogenic phylogroup B2 that harbored the shigatoxin genes stx1/stx2, associated with the cnf, fimA, and aer virulence factors. The qnrA/qnrB, aac(6′)-Ib-cr genes and integrons class 1 with different gene cassettes were detected amongst these CTXR/S isolated strains. The presence of different genetic lineages, associated with resistance and virulence genes in pathogenic bacteria in dairy farms, may complicate antibiotic therapies and pose a potential risk to public health.202236015067
1237120.9803Characterization of Gene Families Encoding Beta-Lactamases of Gram-Negative Rods Isolated from Ready-to-Eat Vegetables in Mexico City. Beta-lactam resistant bacteria, which are commonly resident in tertiary hospitals, have emerged as a worldwide health problem because of ready-to-eat vegetable intake. We aimed to characterize the genes that provide resistance to beta-lactam antibiotics in Enterobacteriaceae, isolated from five commercial salad brands for human consumption in Mexico City. In total, twenty-five samples were collected, grown in blood agar plates, and the bacteria were biochemistry identified and antimicrobial susceptibility testing was done. The carried family genes were identified by endpoint PCR and the specific genes were confirmed with whole genome sequencing (WGS) by Next Generation Sequencing (NGS). Twelve positive cultures were identified and their microbiological distribution was as follows: 8.3% for Enterobacter aerogene (n = 1), 8.3% for Serratia fonticola (n = 1), 16.7% for Serratia marcesens (n = 2), 16.7% for Klebsiella pneumoniae (n = 2), and 50% (n = 6) for Enterobacter cloacae. The endpoint PCR results showed 11 colonies positive for blaBIL (91.7%), 11 for blaSHV (91.7%), 11 for blaCTX (97.7%), 12 for blaDHA (100%), four for blaVIM (33.3%), two for blaOXA (16.7%), two for blaIMP (16.7%), one for blaKPC (8.3%), and one for blaTEM (8.3%) gen; all samples were negative for blaROB, blaCMY, blaP, blaCFX and blaLAP gene. The sequencing analysis revealed a specific genotype for Enterobacter cloacae (blaSHV-12, blaCTX-M-15, blaDHA-1, blaKPC-2); Serratia marcescens (blaSHV-1, blaCTX-M-3, blaDHA-1, blaVIM-2); Klebsiella pneumoniae (blaSHV-12, blaCTX-M-15, blaDHA-1); Serratia fonticola (blaSHV-12, blaVIM-1, blaDHA-1); and, Enterobacter aerogene (blaSHV-1, blaCTX-M-1, blaDHA-1, blaVIM-2, blaOXA-9). Our results indicate that beta-lactam-resistant bacteria have acquired integrons with a different number of genes that provide pan-resistance to beta-lactam antibiotics, including penicillins, oxacillins, cefalosporins, monobactams, carbapenems, and imipenems.201830477153
1167130.9803Investigating the virulence-associated genes and antimicrobial resistance of Escherichia fergusonii Isolated from diseased ostrich chicks. This study investigates the presence of virulence-associated genes and antimicrobial resistance (AMR) in Escherichia fergusonii isolates obtained from ostrich chicks. A total of 287 isolates were recovered from 106 fecal samples from ostrich chicks suffering from diarrhea and subjected to molecular identification and biochemical characterization. E. fergusonii was detected in 10 samples (9.4 %) using two PCR-detection protocols. Notably, the isolates lacked various virulence genes commonly associated with pathogenic E. coli including elt, est, stx, eae, ehly, cdt, iss, iutA, iroN, hlyA, ompT, except for one isolate harboring the astA gene. Antimicrobial susceptibility testing revealed that all isolates were susceptible to ciprofloxacin, while high resistance was observed against amoxicillin clavulanate (AMC), trimethoprim-sulfamethoxazole (SXT), and doxycycline (D). Moreover, eight isolates displayed multidrug resistance (MDR) and four exhibited resistance to 9-11 antimicrobials. The most frequent resistance gene was sul2, which was present in all isolates; the other resistance genes detected consisted of int1 (4/10), int2 (3/10), bla(CMY) (2/10), and qnrS, bla(TEM), bla(CMY), bla(CTX-M), and flo each were detected only in one E. fergusonii Isolate. Plasmid replicon typing identified the presence of I1 (7/10), N (5/10), and Y (1/10). This study provides valuable insights into the virulence and antimicrobial resistance of E. fergusonii isolates from ostrich chicks, highlighting the complexity of antimicrobial resistance mechanisms exhibited by these bacteria. Further research is essential to understand the transmission dynamics and clinical implications of these findings in veterinary and public health settings.202439168034
1413140.9802Occurrence of Carbapenemases, Extended-Spectrum Beta-Lactamases and AmpCs among Beta-Lactamase-Producing Gram-Negative Bacteria from Clinical Sources in Accra, Ghana. Beta-lactamase (β-lactamase)-producing Gram-negative bacteria (GNB) are of public health concern due to their resistance to routine antimicrobials. We investigated the antimicrobial resistance and occurrence of carbapenemases, extended-spectrum β-lactamases (ESBLs) and AmpCs among GNB from clinical sources. GNB were identified using matrix-assisted laser desorption/ionization time of flight-mass spectrometry (MALDITOF-MS). Antimicrobial susceptibility testing was performed via Kirby-Bauer disk diffusion and a microscan autoSCAN system. β-lactamase genes were determined via multiplex polymerase chain reactions. Of the 181 archived GNB analyzed, Escherichia coli and Klebsiella pneumoniae constituted 46% (n = 83) and 17% (n = 30), respectively. Resistance to ampicillin (51%), third-generation cephalosporins (21%), and ertapenem (21%) was observed among the isolates, with 44% being multi-drug resistant (MDR). β-lactamase genes such as AmpCs ((bla(FOX-M) (64%) and bla(DHA-M) and bla(EDC-M) (27%)), ESBLs ((bla(CTX-M) (81%), other β-lactamase genes bla(TEM) (73%) and bla(SHV) (27%)) and carbapenemase ((bla(OXA-)(48) (60%) and bla(NDM) and bla(KPC) (40%)) were also detected. One K. pneumoniae co-harbored AmpC (bla(FOX-M) and bla(EBC-M)) and carbapenemase (bla(KPC) and bla(OXA-)(48)) genes. bla(OXA-)(48) gene was detected in one carbapenem-resistant Acinetobacter baumannii. Overall, isolates were resistant to a wide range of antimicrobials including last-line treatment options. This underpins the need for continuous surveillance for effective management of infections caused by these pathogens in our settings.202337370334
1992150.9802Antimicrobial Resistance Genes, Cassettes, and Plasmids Present in Salmonella enterica Associated With United States Food Animals. The ability of antimicrobial resistance (AR) to transfer, on mobile genetic elements (MGEs) between bacteria, can cause the rapid establishment of multidrug resistance (MDR) in bacteria from animals, thus creating a foodborne risk to human health. To investigate MDR and its association with plasmids in Salmonella enterica, whole genome sequence (WGS) analysis was performed on 193 S. enterica isolated from sources associated with United States food animals between 1998 and 2011; 119 were resistant to at least one antibiotic tested. Isolates represented 86 serotypes and variants, as well as diverse phenotypic resistance profiles. A total of 923 AR genes and 212 plasmids were identified among the 193 strains. Every isolate contained at least one AR gene. At least one plasmid was detected in 157 isolates. Genes were identified for resistance to aminoglycosides (n = 472), β-lactams (n = 84), tetracyclines (n = 171), sulfonamides (n = 91), phenicols (n = 42), trimethoprim (n = 8), macrolides (n = 5), fosfomycin (n = 48), and rifampicin (n = 2). Plasmid replicon types detected in the isolates were A/C (n = 32), ColE (n = 76), F (n = 43), HI1 (n = 4), HI2 (n = 20), I1 (n = 62), N (n = 4), Q (n = 7), and X (n = 35). Phenotypic resistance correlated with the AR genes identified in 95.4% of cases. Most AR genes were located on plasmids, with many plasmids harboring multiple AR genes. Six antibiotic resistance cassette structures (ARCs) and one pseudo-cassette were identified. ARCs contained between one and five resistance genes (ARC1: sul2, strAB, tetAR; ARC2: aac3-iid; ARC3: aph, sph; ARC4: cmy-2; ARC5: floR; ARC6: tetB; pseudo-ARC: aadA, aac3-VIa, sul1). These ARCs were present in multiple isolates and on plasmids of multiple replicon types. To determine the current distribution and frequency of these ARCs, the public NCBI database was analyzed, including WGS data on isolates collected by the USDA Food Safety and Inspection Service (FSIS) from 2014 to 2018. ARC1, ARC4, and ARC5 were significantly associated with cattle isolates, while ARC6 was significantly associated with chicken isolates. This study revealed that a diverse group of plasmids, carrying AR genes, are responsible for the phenotypic resistance seen in Salmonella isolated from United States food animals. It was also determined that many plasmids carry similar ARCs.201931057528
1321160.9801Antimicrobial Resistance and Resistance Genes in Aerobic Bacteria Isolated from Pork at Slaughter. The aim of this study was to investigate the phenotypic and genotypic antimicrobial resistance, integrons, and transferability of resistance markers in 243 aerobic bacteria recovered from pork at slaughter in the People's Republic of China. The organisms belonged to 22 genera of gram-negative bacteria (92.2%) and gram-positive bacteria (7.8%). High levels of resistance were detected to tetracycline, trimethoprim-sulfamethoxazole, and ampicillin (36.2 to 54.3%), and lower levels were detected to nitrofurantoin, cefotaxime, gentamicin, ciprofloxacin, and chloramphenicol (7.8 to 29.2%). Across species, genes conferring antimicrobial resistance were observed with the following frequencies: blaTEM, 40.7%; blaCMY-2, 15.2%; blaCTX-M, 11.5%; sul2, 27.2%; sul1, 14.4%; tet(A), 5.4%; tet(L), 5.4%; tet(M), 5.0%; tet(E), 3.7%; tet(C), 3.3%; tet(S), 2.5%; and tet(K), 0.8%. Various antimicrobial resistance genes were found in new carriers: blaTEM in Lactococcus garvieae, Myroides odoratimimus, Aeromonas hydrophila, Staphylococcus sciuri, Raoultella terrigena, Macrococcus caseolyticus, Acinetobacter ursingii, Sphingobacterium sp., and Oceanobacillus sp.; blaCMY-2 in Lactococcus lactis, Klebsiella oxytoca, Serratia marcescens, Acinetobacter baumannii, and Myroides phaeus; tet(L) in M. caseolyticus; sul1 in Vibrio cincinnatiensis; sul2 in Acinetobacter bereziniae, Acinetobacter johnsonii, and V. cincinnatiensis; and the class 1 integron and gene cassette aadA2 in V. cincinnatiensis. Approximately 6.6% of isolates contained class 1 integrons, and one isolate harbored class 2 integrons. Plasmid associated intI1 and androgen receptor- encoding genes were transferred into Escherichia coli J53 and E. coli DH5α by conjugation and transformation experiments, respectively. Our study highlights the importance of aerobic bacteria from pork as reservoirs for antimicrobial resistance genes and mobile genetic elements that can readily be transferred intra- and interspecies.201627052863
1093170.9800The rate of frequent co-existence of plasmid-mediated quinolone resistance (PMQR) and extended-spectrum β-lactamase (ESBL) genes in Escherichia coli isolates from retail raw chicken in South Korea. Since plasmid-encoded antibiotic resistance facilitates the emergence of antibiotic-resistant bacteria, the increasing prevalence of Escherichia coli harboring plasmid-mediated quinolone resistance (PMQR) and extended-spectrum β-lactamase (ESBL) genes is a public health concern. The objective of this study is to investigate the co-existence of PMQR and ESBL genes in E. coli isolates from retail raw chicken in South Korea. Among 67 ESBL-producing E. coli isolates from 40 retail raw chicken, more than half of them carried PMQR genes, including qnrS, aac(6')-Ib-cr, and oqxAB. The qnrS was predominantly (91.4%) detected in E. coli isolates carrying both PMQR and ESBL. The aac(6')-Ib-cr was detected in seven ESBL-producing E. coli strains, and 85.7% of the aac(6')-Ib-cr-positive strains also carried qnrS. Moreover, the strains co-harboring qnrS and aac(6')-Ib-cr exhibited increased resistance to ciprofloxacin and kanamycin. These results demonstrate that PMQR genes are frequently detected in ESBL-producing E. coli isolates from retail raw chicken in South Korea.202235646407
1104180.9800Predominance of Multidrug-Resistant Gram-Negative Bacteria Isolated from Supermarket Retail Seafood in Japan. Reports have documented antimicrobial usage in aquaculture, and the aquatic ecosystem can be considered a genetic storage site for antibiotic-resistant bacteria. This study assessed the prevalence of antimicrobial resistance (AMR) among Gram-negative bacteria recovered from retail seafood in Hiroshima, Japan. A total of 412 bacteria were isolated and screened for the presence of β-lactamases, acquired carbapenemases, and mobile colistin-resistance (mcr) genes. Forty-five (10.9%) isolates were dominated by Morganella (28%), Proteus (22%), Aeromonas (14%), Citrobacter (8%), and Escherichia (8%) and carried AMR genes. The identified AMR genes included those encoded in integrons (19), aac(6՛)-Ib (11), bla(TEM-1) (7), bla(CTX-M-like) (12), bla(CTX-M-65) (2), bla(SHV-12) (1), bla(SHV-27) (1), bla(OXA-10) (1), bla(OXA-2) (1), and mcr (2). The most common clinical resistances were against ampicillin, colistin, sulfamethoxazole/trimethoprim, tetracycline, and ciprofloxacin. Multidrug resistance (MDR) occurred in 27 (60%) AMR isolates, and multiple antibiotic resistance indices ranged from 0.2 to 0.8. A conjugation experiment showed that 10 of the 11 selected MDR strains harbored conjugable plasmids, although PCR-based replicon typing described seven strains as untypable. IncF replicon was identified in MDR extended-spectrum β-lactamase-producing Escherichia coli of the pathogenic B2 phylogroup. Our findings suggest that retail seafood harbors MDR bacteria of human interest that require strict resistance surveillance in the seafood production continuum.202338138079
1311190.9800Prevalence and Molecular Characterization of Antimicrobial Resistance in Escherichia coli Isolated from Raw Milk and Raw Milk Cheese in Egypt. The goal of this study was to examine antimicrobial resistance and characterize the implicated genes in 222 isolates of Escherichia coli from 187 samples of raw milk and the two most popular cheeses in Egypt. E. coli isolates were tested for susceptibility to 12 antimicrobials by a disk diffusion method. Among the 222 E. coli isolates, 66 (29.7%) were resistant to one or more antimicrobials, and half of these resistant isolates showed a multidrug resistance phenotype (resistance to at least three different drug classes). The resistance traits were observed to tetracycline (27.5%), ampicillin (18.9%), streptomycin (18.5%), sulfamethoxazole-trimethoprim (11.3%), cefotaxime (4.5%), kanamycin (4.1%), ceftazidime (3.6%), chloramphenicol (2.3%), nalidixic acid (1.8%), and ciprofloxacin (1.4%). No resistance to fosfomycin and imipenem was observed. Tetracycline resistance genes tetA, tetB, and tetD were detected in 53 isolates, 9 isolates, and 1 isolate, respectively, but tetC was not detected. Aminoglycoside resistance genes strA, strB, aadA, and aphA1 were detected in 41, 41, 11, and 9 isolates, respectively. Sulfonamide resistance genes sul1, sul2, and sul3 were detected in 7, 25, and 3 isolates, respectively. Of 42 ampicillin-resistant isolates, bla(TEM), bla(CTX-M), and bla(SHV) were detected in 40, 9, and 3 isolates, respectively, and 10 (23.8%) ampicillin-resistant isolates were found to produce extended-spectrum β-lactamase. Each bla gene of extended-spectrum β-lactamase-producing E. coli was further subtyped to be bla(CTX-M-15), bla(CTX-M-104), bla(TEM-1), and bla(SHV-12). The class 1 integron was also detected in 28 resistant isolates, and three different patterns were obtained by PCR-restriction fragment length polymorphism. Sequencing analysis of the variable region revealed that four isolates had dfrA12/orfF/aadA2, two had aadA22, and one had dfrA1/aadA1. These data suggest that antimicrobial-resistant E. coli are widely distributed in the milk production and processing environment in Egypt and may play a role in dissemination of antimicrobial resistance to other pathogenic and commensal bacteria.201829323530