scholarly journals Antimicrobial susceptibility, multilocus sequence typing, and virulence of listeria isolated from a slaughterhouse in Jiangsu, China

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Liting Wu ◽  
Hongduo Bao ◽  
Zhengquan Yang ◽  
Tao He ◽  
Yuan Tian ◽  
...  

Abstract Background Listeria monocytogenes is one of the deadliest foodborne pathogens. The bacterium can tolerate severe environments through biofilm formation and antimicrobial resistance. This study aimed to investigate the antimicrobial susceptibility, resistance genes, virulence, and molecular epidemiology about Listeria from meat processing environments. Methods This study evaluated the antibiotic resistance and virulence of Listeria isolates from slaughtering and processing plants. All isolates were subjected to antimicrobial susceptibility testing using a standard microbroth dilution method. The harboring of resistant genes was identified by polymerase chain reaction. The multilocus sequence typing was used to determine the subtyping of the isolates and characterize possible routes of contamination from meat processing environments. The virulence of different STs of L. monocytogenes isolates was evaluated using a Caco-2 cell invasion assay. Results A total of 59 Listeria isolates were identified from 320 samples, including 37 L. monocytogenes isolates (62.71%). This study evaluated the virulence of L. monocytogenes and the antibiotic resistance of Listeria isolates from slaughtering and processing plants. The susceptibility of these 59 isolates against 8 antibiotics was analyzed, and the resistance levels to ceftazidime, ciprofloxacin, and lincomycin were as high as 98.31% (L. m 37; L. innocua 7; L. welshimeri 14), 96.61% (L. m 36; L. innocua 7; L. welshimeri 14), and 93.22% (L. m 35; L. innocua 7; L. welshimeri 13), respectively. More than 90% of the isolates were resistant to three to six antibiotics, indicating that Listeria isolated from meat processing environments had high antimicrobial resistance. Up to 60% of the isolates harbored the tetracycline-resistance genes tetA and tetM. The frequency of ermA, ermB, ermC, and aac(6′)-Ib was 16.95, 13.56, 15.25, and 6.78%, respectively. Notably, the resistant phenotype and genotype did not match exactly, suggesting that the mechanisms of antibiotic resistance of these isolates were likely related to the processing environment. Multilocus sequence typing (MLST) revealed that 59 Listeria isolates were grouped into 10 sequence types (STs). The dominant L. monocytogenes STs were ST5, ST9, and ST121 in the slaughtering and processing plant of Jiangsu province. Moreover, ST5 subtypes exhibited high invasion in Caco-2 cells compared with ST9 and ST121 cells. Conclusion The dominant L. monocytogenes ST5 persisted in the slaughtering and processing plant and had high antimicrobial resistance and invasion characteristics, illustrating a potential risk in food safety and human health.

2021 ◽  
Author(s):  
Liting Wu ◽  
Hongduo Bao ◽  
Zhengquan Yang ◽  
Tao He ◽  
Yuan Tian ◽  
...  

Abstract Background: Listeria monocytogenes is one of the deadliest foodborne pathogens, and the bacterium can tolerate severe environments through biofilm formation and antimicrobial resistance. The objective of this study was to investigate the antimicrobial susceptibility, resistance genes,virulence and molecular epidemiology about Listeria from meat processing environments. Methods: This study evaluated the antibiotic resistance and virulence of Listeria isolates from slaughtering and processing plants. All isolates were subjected to antimicrobial susceptibility testing by using a standard microbroth dilution method. The carrying of resistant genes were identified by Polymerase Chain Reaction (PCR). The multilocus sequence typing (MLST) was determined subtyping of the isolates and to characterize possible routes of contamination from meat processing environments. The virulence of different STs of L. monocytogenes isolates were evaluated by Caco-2 cells invasion assay. Results: A total of 59 Listeria isolates were identified from 320 samples, including 37 L. monocytogenes (62.71%). This study evaluated the virulence of L. monocytogenes and antibiotic resistance of Listeria isolates from slaughtering and processing plants. The susceptibility of these 59 isolates against eight antibiotics was analyzed, and the resistance levels to ceftazidime, ciprofloxacin, and lincomycin were as high as 98.31% (L. m 37; L. innocua 7; L. welshimeri 14), 96.61% (L. m 36; L. innocua 7; L. welshimeri 14), and 93.22% (L. m 35; L. innocua 7; L. welshimeri 13) respectively. Over 90% of the isolates were resistant to 3-6 antibiotics, indicating that Listeria isolated from meat processing environments has high antimicrobial resistance. Up to 60% of the isolates carried the tetracycline-resistance genes tetA and tetM. The frequencies of ermA, ermB, ermC, and aac(6’)-Ib were 16.95%, 13.56%, 15.25%, and 6.78%, respectively. Notably, the resistant phenotype and genotype did not match exactly, suggesting that the mechanisms of antibiotic resistance of these isolates were likely related to the processing environment. Multilocus sequence typing (MLST) revealed that 59 Listeria isolates were grouped into 10 sequence types (STs). The dominant L. monocytogenes STs were ST5, ST9, and ST121 in the slaughtering and processing plant of Jiangsu province. Moreover, ST5 subtypes exhibited high invasion in Caco-2 cells compared with ST9 and ST121. Conclusions: The results of this study predict a prevalence of Listeria contamination in the slaughtering and processing plant , and resistance of the ST5 subtypes isolates to the antimicrobials may cause potential public health risks.


2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Jie Yang ◽  
Siwei Gao ◽  
Yajie Chang ◽  
Mingliu Su ◽  
Yutong Xie ◽  
...  

This study aimed to investigate the prevalence and antimicrobial resistance of Salmonella spp. isolated from large-scale breeder farms in Shandong Province, China. A total of 63 Salmonella isolates (63/409, 15.4%) were identified from 409 samples collected from five large-scale breeder farms in Shandong Province. These Salmonella isolates were assayed for serotype, antimicrobial susceptibility, prevalence of class 1 integrons, quinolone resistance genes, and β-lactamase genes and subtyped by multilocus sequence typing (MLST). Among these isolates, S. Enteritidis (100%) was the predominant serovar, and high antimicrobial resistance rates to nalidixic acid (100.0%), streptomycin (100.0%), ampicillin (98.4%), and erythromycin (93.7%) were observed. All of the isolates carried blaTEM. MLST results showed that only one sequence type (ST11) was identified. Our findings indicated that Salmonella was generally prevalent not only on broiler farms but also on breeder farms.


2012 ◽  
Vol 75 (8) ◽  
pp. 1486-1491 ◽  
Author(s):  
MUEEN ASLAM ◽  
MOUSSA S. DIARRA ◽  
LUKE MASSON

The objective of this study was to assess the antimicrobial resistance and virulence genotypes of Enterococcus faecalis isolated from samples obtained from a commercial pork processing plant. A total of 200 samples were randomly obtained from carcasses after bleeding (BC; 50 samples) and pasteurization (PC; 100 samples) and from retail pork products (RP; 50 samples). One isolate from each E. faecalis–positive sample was analyzed for antimicrobial susceptibility and characterized using a enterococcal microarray for analysis of resistance and virulence genes. E. faecalis was isolated from 79.5% of BC samples, 2% of PC samples, and 72.7% of RP samples. Resistance to the clinically important drugs ciprofloxacin (one isolate each from BC and RP samples) and daptomycin (one isolate each from PC and RP samples) was found. Multiresistance (to five or more antimicrobials) was more common in E. faecalis isolates from BC (77.4% of isolates) samples than those from PC (25%) and RP (37.6%) samples. Resistance to kanamycin (43.5%) and streptomycin (69.2%) was noted mostly in E. faecalis from BC samples. The most common resistance genes (>5% prevalence) found in E. faecalis were those for aminoglycosides (aac(6), aphA3, and aadE), macrolides-lincosamide (ermB, ermA, sat(4), and linB), and tetracyclines (tetL, tetM, and tetO). The virulence genes expressing adhesion (ace, efaAfs, and agrBfs), gelatinase (gelE), and pheromone (cAM, ccF10, cob, and cpd1) factors were found in the majority of isolates. Significant associations were found between resistance and virulence genes, suggesting their possible relationship. These data suggest that carcasses entering the final product processing area are mostly free of E. faecalis but are recontaminated with antimicrobial-resistant strains during processing. The source of these contaminants remains to be identified; however, these results underscore the importance of E. faecalis as a reservoir of resistance and virulence genes.


2009 ◽  
Vol 72 (3) ◽  
pp. 608-611 ◽  
Author(s):  
JYHSHIUN LIN ◽  
KUANG-SHENG YEH ◽  
HSUEH-TAO LIU ◽  
JIUNN-HORNG LIN

Staphylococcus aureus is a cause of many diseases in both humans and animals. This pathogen is also a major target in the screening of slaughterhouse carcasses to monitor hygienic conditions during slaughter. During 2004 to 2006, S. aureus was recovered from 8.8% (38 of 430), 11.3% (77 of 680), and 4.3% (13 of 300) of pork carcass samples, respectively, collected at 53 slaughterhouses in Taiwan. During 2003 to 2005, it was recovered from 0.3% (1 of 305), 0.4% (1 of 260), and 7.8% (31 of 395) of rinse fluids from chicken carcasses, respectively, collected at 17 meat processing plants. The minimum dilution method was used to determine antimicrobial susceptibility (MICs) of these strains (n = 103) as well as those collected from pork and chicken carcasses (n = 104) in a previous study beginning in 2000. All 207 strains were sensitive to nitrofurantoin and vancomycin. Over 50% were resistant to clindamycin (MIC that inhibited 90% of strains [MIC90] = 32 μg/ml) and tetracycline (MIC90 = 64 μg/ml). The percentages resistant to methicillin (oxacillin), chloramphenicol, erythromycin, and tylosin were 19.4% (40 of 207), 18.8% (39 of 207), 23.2% (48 of 207), and 20.8% (43 of 207) with MIC90sof8, 64, ≥64, and ≥128 μg/ml, respectively. The methicillin-resistant S. aureus (MRSA) strains exhibited resistance to more antibiotics than did the methicillin-susceptible strains, and 87.5% (35 of 40) of the MRSA strains carried the mecA gene sequence. Since MRSA infections have become a public health concern in both communities and hospitals, testing for the presence of MRSA in animal carcasses during slaughtering operations is warranted.


AMB Express ◽  
2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Quan Li ◽  
Jian Yin ◽  
Zheng Li ◽  
Zewei Li ◽  
Yuanzhao Du ◽  
...  

AbstractSalmonella is an important food-borne pathogen associated with public health and high economic losses. To investigate the prevalence and the characteristics of Salmonella in a pig slaughterhouse in Yangzhou, a total of 80 Salmonella isolates were isolated from 459 (17.43%) samples in 2016–2017. S. Derby (35/80, 43.75%) was the most prevalent, followed by S. Rissen (16/80, 20.00%) and S. Newlands (11/80, 13.75%). The highest rates of susceptibility were observed to cefoxitin (80/80, 100.0%) and amikacin (80/80, 100.0%), followed by aztreonam (79/80, 98.75%) and nitrofurantoin (79/80, 98.75%). The highest resistance rate was detected for tetracycline (65/80, 81.25%), followed by ampicillin (60/80, 75.00%), bactrim (55/80, 68.75%), and sulfisoxazole (54/80, 67.50%). Overall, 91.25% (73/80) of the isolates were resistant to at least one antibiotic, while 71.25% (57/80) of the isolate strains were multidrug resistant in the antimicrobial susceptibility tested. In addition, 86.36% (19/22) of the 22 antimicrobial resistance genes in the isolates were identified. Our data indicated that the resistance to certain antimicrobials was significantly associated, in part, with antimicrobial resistance genes. Furthermore, 81.25% (65/80) isolates harbored the virulence gene of mogA, of which 2 Salmonella Typhimurium isolates carried the mogA, spvB and spvC virulence genes at the same time. The results showed that swine products in the slaughterhouse were contaminated with multidrug resistant Salmonella commonly, especially some isolates carry the spv virulence genes. The virulence genes might facilitate the dissemination of the resistance genes to consumers along the production chain, suggesting the importance of controlling Salmonella during slaughter for public health.


2017 ◽  
Vol 62 (No. 3) ◽  
pp. 169-177 ◽  
Author(s):  
TH Chung ◽  
SW Yi ◽  
BS Kim ◽  
WI Kim ◽  
GW Shin

The present study sought to identify pathogens associated with septicaemia in the Chinese soft-shelled turtle (Pelodiscus sinensis) and to characterise antibiotic resistance in these pathogens. Twenty-three isolates recovered from the livers of diseased soft-shelled turtles were genetically identified as Aeromonas hydrophila (n = 8), A. veronii (n = 3), Citrobacter freundii (n = 4), Morganella morganii (n = 3), Edwardsiella tarda (n = 2), Wohlfahrtiimonas chitiniclastica (n = 1), Chryseobacterium sp. (n = 1), and Comamonas sp. (n = 1). Most isolates (n = 21) were resistant to ampicillin whereas a low percentage of isolates was susceptible to aminoglycosides (amikacin, gentamicin, and tobramycin). PCR assays and sequence analysis revealed the presence of the qnrS2 and bla<sub>TEM</sub> antibiotic resistance genes in all isolates. The bla<sub>DHA-1</sub>, bla<sub>CTX-M-14</sub> and bla<sub>CMY-2</sub> genes were harboured by 17.4% (n = 4), 13.5% (n = 3) and 8.7% (n = 2) of the strains, respectively. One or more tetracycline resistance genes were detected in 60.9% (n = 14) of the isolates. Four isolates (17.4%) harboured single or multiple class 1 integron cassettes. Collectively, a variety of bacterial pathogens were involved in the occurrence of septicaemia in Chinese soft-shelled turtles and most of the isolates had multi-antibiotic resistant phenotypes. To our knowledge, the present report is the first to identify W. chitiniclastica and Comamonas sp. as causes of septicaemia in soft-shelled turtles and the first to identify Aeromonas spp. with bla<sub>CTX-M-14</sub> and bla<sub>DHA-1</sub> resistance genes.


2019 ◽  
Author(s):  
Sanjeet Kumar ◽  
Kanika Bansal ◽  
Prashant P. Patil ◽  
Amandeep Kaur ◽  
Satinder Kaur ◽  
...  

ABSTRACTWe report first complete genome sequence and analysis of an extreme drug resistance (XDR) nosocomial Stenotrophomonas maltophilia that is resistant to the mainstream drugs i.e. trimethoprim/sulfamethoxazole (TMP/SXT) and levofloxacin. Taxonogenomic analysis revealed it to be a novel genomospecies of the Stenotrophomonas maltophilia complex (Smc). Comprehensive genomic investigation revealed fourteen dynamic regions (DRs) exclusive to SM866, consisting of diverse antibiotic resistance genes, efflux pumps, heavy metal resistance, various transcriptional regulators etc. Further, resistome analysis of Smc clearly depicted SM866 to be an enriched strain, having diversified resistome consisting of sul1 and sul2 genes. Interestingly, SM866 does not have any plasmid but it harbors two diverse super-integrons of chromosomal origin. Apart from genes for sulfonamide resistance (sul1 and sul2), both of these integrons harbor an array of antibiotic resistance genes linked to ISCR (IS91-like elements common regions) elements. These integrons also harbor genes encoding resistance to commonly used disinfectants like quaternary ammonium compounds and heavy metals like mercury. Hence, isolation of a novel strain belonging to a novel sequence type (ST) and genomospecies with diverse array of resistance from a tertiary care unit of India indicates extent and nature of selection pressure driving XDRs in hospital settings. There is an urgent need to employ complete genome based investigation using emerging technologies for tracking emergence of XDR at the global level and designing strategies of sanitization and antibiotic regime.Impact StatementThe hospital settings in India have one of the highest usage of antimicrobials and heavy patient load. Our finding of a novel clinical isolate of S. maltophilia complex with two super-integrons harbouring array of antibiotic resistance genes along with antimicrobials resistance genes indicates the extent and the nature of selection pressures in action. Further, the presence of ISCR type of transposable elements on both integrons not only indicates its propensity to transfer resistome but also their chromosomal origin suggests possibilities for further genomic/phenotypic complexities. Such complex cassettes and strain are potential threat to global health care. Hence, there is an urgent need to employ cost-effective long read technologies to keep vigilance on novel and extreme antimicrobial resistance pathogens in populous countries. There is also need for surveillance for usage of antimicrobials for hygiene and linked/rapid co-evolution of extreme drug resistance in nosocomial pathogens. Our finding of the chromosomal encoding XDR will shed a light on the need of hour to understand the evolution of an opportunistic nosocomial pathogen belonging to S. maltophilia.RepositoriesComplete genome sequence of Stenotrophomonas maltophilia SM866: CP031058


mBio ◽  
2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Emily Crossette ◽  
Jordan Gumm ◽  
Kathryn Langenfeld ◽  
Lutgarde Raskin ◽  
Melissa Duhaime ◽  
...  

ABSTRACT We demonstrate that an assembly-independent and spike-in facilitated metagenomic quantification approach can be used to screen and quantify over 2,000 genes simultaneously, while delivering absolute gene concentrations comparable to those for quantitative PCR (qPCR). DNA extracted from dairy manure slurry, digestate, and compost was spiked with genomic DNA from a marine bacterium and sequenced using the Illumina HiSeq4000. We compared gene copy concentrations, in gene copies per mass of sample, of five antimicrobial resistance genes (ARGs) generated with (i) our quantitative metagenomic approach, (ii) targeted qPCR, and (iii) a hybrid quantification approach involving metagenomics and qPCR-based 16S rRNA gene quantification. Although qPCR achieved lower quantification limits, the metagenomic method avoided biases caused by primer specificity inherent to qPCR-based methods and was able to detect orders of magnitude more genes than is possible with qPCR assays. We used the approach to simultaneously quantify ARGs in the Comprehensive Antimicrobial Resistance Database (CARD). We observed that the total abundance of tetracycline resistance genes was consistent across different stages of manure treatment on three farms, but different samples were dominated by different tetracycline resistance gene families. IMPORTANCE qPCR and metagenomics are central molecular techniques that have offered insights into biological processes for decades, from monitoring spatial and temporal gene dynamics to tracking ARGs or pathogens. Still needed is a tool that can quantify thousands of relevant genes in a sample as gene copies per sample mass or volume. We compare a quantitative metagenomic approach with traditional qPCR approaches in the quantification of ARG targets in dairy manure samples. By leveraging the benefits of nontargeted community genomics, we demonstrate high-throughput absolute gene quantification of all known ARG sequences in environmental samples.


Animals ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 97
Author(s):  
Zunita Zakaria ◽  
Latiffah Hassan ◽  
Zawiyah Sharif ◽  
Norazah Ahmad ◽  
Rohaya Mohd Ali ◽  
...  

This study was undertaken to determine the virulence, antimicrobial resistance and molecular subtypes of Salmonella in the Central Region of Peninsular Malaysia. A total of 45 Salmonella Enteritidis were detected from live chicken (cloacal swab), and chicken products (fresh and ready-to-eat meat) samples upon cultural isolation and serotyping. Similarly, an antimicrobial susceptibility test based on the Kirby Bauer disk diffusion method as well as antimicrobial resistance AMR genes, virulence determinants and multilocus sequence typing (MLST) typing were conducted after the Whole Genome Sequencing and analysis of the isolates. The results indicate that sequence types ST1925 (63.7%), and ST11 (26.5%) were the predominant out of the seven sequence types identified (ST292, ST329, ST365, ST423 and ST2132). The phenotypic antimicrobial profile corresponds to the genotypic characterization in that the majority of the isolates that exhibited tetracycline, gentamycin and aminoglycoside resistance; they also possessed the tetC and blaTEM β-Lactam resistance genes. However, isolates from cloacal swabs showed the highest number of resistance genes compared to the chicken products (fresh and ready-to-eat meat) samples. Furthermore, most of the virulence genes were found to cluster in the Salmonella pathogenicity island (SPI). In this study, all the isolates were found to possess SPI-1, which codes for the type III secretion system, which functions as actin-binding proteins (SptP and SopE). The virulence plasmid (VP) genes (spvB, spvC) were present in all genotypes except ST365. The findings of this study, particularly with regard to the molecular subtypes and AMR profiles of the Salmonella Enteritidis serotype shows multidrug-resistance features as well as genetic characteristics indicative of high pathogenicity.


2011 ◽  
Vol 74 (8) ◽  
pp. 1245-1251 ◽  
Author(s):  
ANGELA COOK ◽  
RICHARD J. REID-SMITH ◽  
REBECCA J. IRWIN ◽  
SCOTT A. McEWEN ◽  
VIRGINIA YOUNG ◽  
...  

This study estimated the prevalence of Salmonella, Campylobacter, and Escherichia coli isolates in fresh retail grain-fed veal obtained in Ontario, Canada. The prevalence and antimicrobial resistance patterns were examined for points of public health significance. Veal samples (n = 528) were collected from February 2003 through May 2004. Twenty-one Salmonella isolates were recovered from 18 (4%) of 438 samples and underwent antimicrobial susceptibility testing. Resistance to one or more antimicrobials was found in 6 (29%) of 21 Salmonella isolates; 5 (24%) of 21 isolates were resistant to five or more antimicrobials. No resistance to antimicrobials of very high human health importance was observed. Ampicillin-chloramphenicol-streptomycin-sulfamethoxazole-tetracycline resistance was found in 5 (3%) of 21 Salmonella isolates. Campylobacter isolates were recovered from 5 (1%) of 438 samples; 6 isolates underwent antimicrobial susceptibility testing. Resistance to one or more antimicrobials was documented in 3 (50%) of 6 Campylobacter isolates. No Campylobacter isolates were resistant to five or more antimicrobials or category I antimicrobials. E. coli isolates were recovered from 387 (88%) of 438 samples; 1,258 isolates underwent antimicrobial susceptibility testing. Resistance to one or more antimicrobials was found in 678 (54%) of 1,258 E. coli isolates; 128 (10%) of 1,258 were resistant to five or more antimicrobials. Five (0.4%) and 7 (0.6%) of 1,258 E. coli isolates were resistant to ceftiofur and ceftriaxone, respectively, while 34 (3%) of 1,258 were resistant to nalidixic acid. Ciprofloxacin resistance was not detected. There were 101 different resistance patterns observed among E. coli isolates; resistance to tetracycline alone (12.7%, 161 of 1,258) was most frequently observed. This study provides baseline prevalence and antimicrobial resistance data and highlights potential public health concerns.


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