scholarly journals Genetic Characterization of Multidrug-Resistant Salmonella Typhimurium Carrying Mcr-1 in China

2021 ◽  
Author(s):  
Zhang Haoran ◽  
Huang Yong ◽  
Liang Beibei ◽  
Xie Jing ◽  
Xiang Ying ◽  
...  
Keyword(s):  
Resistance Gene ◽  
Insertion Sequence ◽  
Southern Blotting ◽  
Multidrug Resistant ◽  
Polymorphism Analysis ◽  
Intestinal Infections ◽  
Different Types ◽  
Reference Plasmid ◽  
Rapid Emergence

Abstract Background: With the rapid emergence of plasmid mediated polymyxin resistance gene mcr-1, multidrug-resistant Salmonella caused great troubles in clinical treatment and attracted extensive attention. Here we report multidrug-resistant Salmonella strains harboring mcr-1 in China, which are resistant to both polymyxin, traditional antibiotics and even clinically wide-used antibiotics. Methods: We screened 1454 strains of Salmonella collected in our laboratory from 2006 to 2018 from 3 provinces or regions for mcr-1 by PCR. Antimicrobial susceptibility testing was determined. Plasmid conjugation assays were carried out to analysis the transferability of polymyxin resistance. Genetic polymorphism analysis of Salmonella was performed using the PFGE, and the plasmid profiles were characterized by S1-PFGE and southern blotting. The plasmids harboring mcr-1 were sequenced and compared. Results: Eleven S. Typhimurium isolates harboring mcr-1 with polymyxin resistance (MICs 4μg/ml) were identified from intestinal infections and foods in China. All S. Typhimurium isolates were multidrug-resistant to traditional antibiotics and even clinically wide-used antibiotics. Three types of plasmids harboring mcr-1 were recovered (IncHI2, IncX4 and IncI2). Compared with the reference plasmid, IncX4 and IncI2 plasmids had extremely similar typical backbone, and contain only mcr-1 resistance gene. However, IncHI2 were the most diverse type of plasmid due to containing a large MDR region, including blaCTX-M, oqxB, sul, aph, aadA and blaTEM. IncHI2 plasmids were observed to contain only one or no insertion sequence ISApl1 around mcr-1, without forming a circular intermediate. Conclusion: With the horizontal transfer of different types of plasmids, mcr-1 is widely spread worldwide. These prevalent plasmids are responsible for resistance to polymyxin, traditional antibiotics and even clinically wide-used antibiotics resulting from transmission of mcr-1 and other resistance genes. Our studying emphasizes the necessity to jointly monitor its international epidemic and preemptive further upgrade.

scholarly journals Genomic Characterization of A Multidrug-resistant Citrobacter freundii Strain ZT01-0079 Co-Producing blaNDM-1 and blaSHV-12 using MiSeq and MinION

2020 ◽  
Author(s):  
Tingyan Zhang ◽  
Yanfeng Lin ◽  
Zhonghong Li ◽  
Xiong Liu ◽  
Jinhui Li ◽  
...  
Keyword(s):  
Resistance Genes ◽  
Southern Blotting ◽  
Multiple Drug Resistance ◽  
Carbapenem Resistance ◽  
Multidrug Resistant ◽  
Multiple Drug ◽  
Citrobacter Freundii ◽  
Rapid Spread ◽  
Genomic Characterization

Abstract Background: The emergence of multi-drug resistant Citrobacter freundii poses daunting challenges to the treatment of clinical infections. The purpose of this study was to characterize the genome of a C. freundii strain with an IncX3 plasmid encoding both the blaNDM-1 and blaSHV-12 genes.Methods: Strain ZT01-0079 was isolated from a clinical urine sample. The Vitek2 system was used for identification and antimicrobial susceptibility testing. The presence of blaNDM-1 was detected by PCR and sequencing. Conjugation experiments and Southern blotting were performed to determine the transferability of the blaNDM-1- carrying plasmid. Nanopore and Illumina sequencing were performed to better understand the genomic characteristics of the strain.Results: Strain ZT01-0079 was identified as C. freundii, and the coexistence of blaNDM-1 and multiple drug resistance genes was confirmed. Electrophoresis and Southern blotting showed that blaNDM-1 was located on a ~53kb IncX3 plasmid. The NDM-1-encoding plasmid was successfully transferred at a frequency of 1.68×10−3. Both blaNDM-1 and blaSHV-12 were located on the self-transferable IncX3 plasmid.Conclusion: The rapid spread of the IncX3 plasmid highlights the importance of continuous monitoring of the prevalence of NDM-1-encoding Enterobacteriaceae. Mutations of existing carbapenem resistance genes will bring formidable challenges to clinical treatment.

scholarly journals Characterization of IS18, an Element Capable of Activating the Silent aac(6′)-Ij Gene ofAcinetobacter sp. 13 Strain BM2716 by Transposition

1998 ◽  
Vol 42 (10) ◽  
pp. 2759-2761 ◽  
Author(s):  
Eric Rudant ◽  
Patrice Courvalin ◽  
Thierry Lambert
Keyword(s):  
Resistance Gene ◽  
Insertion Sequence ◽  
Resistant Mutant ◽  
Open Reading Frame ◽  
Inverted Repeats ◽  
Aminoglycoside Resistance ◽  
Reading Frame ◽  
Terminal Inverted Repeats ◽  
Hybrid Promoter

ABSTRACT Insertion sequence IS18 was detected by analysis of the spontaneous aminoglycoside resistant mutant Acinetobactersp. 13 strain BM2716-1. Insertion of the element upstream from the silent acetyltransferase gene aac(6′)-Ij created a hybrid promoter that putatively accounts for the expression of the aminoglycoside resistance gene. The 1,074-bp IS18 element contained partially matched (20 out of 26 bases) terminal inverted repeats, one of which overlapped the 3′ end of a 935-bp open reading frame potentially encoding a protein related to the transposases of the IS30 family. IS18 was found in 6 out of 29 strains of Acinetobacter sp. 13 but not in 10 strains each of A. baumannii and A. haemolyticus.

scholarly journals Detection of an Escherichia coli Sequence Type 167 Strain with Two Tandem Copies ofblaNDM-1in the Chromosome

2016 ◽  
Vol 55 (1) ◽  
pp. 199-205 ◽  
Author(s):  
Ping Shen ◽  
Maoli Yi ◽  
Ying Fu ◽  
Zhi Ruan ◽  
Xiaoxing Du ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Insertion Sequence ◽  
Southern Blotting ◽  
Multidrug Resistant ◽  
Sequence Type ◽  
New Delhi ◽  
Genomic Context ◽  
Content Type ◽  
Link Type ◽  
Reference Genomes

ABSTRACTNew Delhi metallo-β-lactamase-1 (NDM-1)-producingEnterobacteriaceaehas disseminated rapidly throughout the world and poses an urgent threat to public health. Previous studies confirmed that theblaNDM-1gene is typically carried in plasmids but rarely in chromosome. We discovered a multidrug-resistantEscherichia colistrain Y5, originating from a urine sample and containing theblaNDM-1gene, which did not transfer by either conjugation or electrotransformation. We confirmed the possibility of its chromosome location by S1-pulsed-field gel electrophoresis (PFGE) and XbaI-PFGE, followed by Southern blotting. To determine the genomic background ofblaNDM-1, the genome of Y5 was completely sequenced and compared to other reference genomes. The results of our study revealed that this isolate consists of a 4.8-Mbp chromosome and three plasmids, it is an epidemic clone of sequence type (ST) 167, and it shows 99% identity withEscherichia coli6409 (GenBank accession no.CP010371), which lacks the sameblaNDM-1gene-surrounding structure as Y5. TheblaNDM-1gene is embedded in the chromosome along with two tandem copies of an insertion sequence common region 1 (ISCR1) element (sul1-ARR-3-cat-blaNDM-1-bleo-ISCR1), which appears intact in the plasmid fromProteus mirabilis(GenBank accession no.KP662515). The genomic context indicates that the ISCR1element mediated theblaNDM-1transposition from a single source plasmid to the chromosome. Our study is the first report of anEnterobacteriaceaestrain harboring a chromosomally integratedblaNDM-1, which directly reveals the vertical spreading pattern of the gene. Close surveillance is urgently needed to monitor the emergence and potential spread of ST167 strains that harborblaNDM-1.

Characterization of Quinolone Resistance in Salmonella enterica from Farm Animals in China

2017 ◽  
Vol 80 (10) ◽  
pp. 1742-1748 ◽  
Author(s):  
Ting-Ting Cao ◽  
Guo-Hui Deng ◽  
Liang-Xing Fang ◽  
Run-Shi Yang ◽  
Jian Sun ◽  
...  
Keyword(s):  
Resistance Gene ◽  
Salmonella Enterica ◽  
Antimicrobial Agents ◽  
Multidrug Resistant ◽  
Quinolone Resistance ◽  
Farm Animals ◽  
Gyra Gene ◽  
Republic Of China ◽  
Resistance Plasmids

ABSTRACT This study was focused on the prevalence and antimicrobial susceptibilities of Salmonella directly isolated at animal clinics in Guangdong, People's Republic of China. The isolation rates from chickens, ducks, and pigs were 11.3% (11 of 97 samples), 15.4% (53 of 344 samples), and 3.0% (13 of 434 samples), respectively. Among the 77 Salmonella enterica isolates, the most predominant serovar was Typhimurium (81.8%, 63 isolates), followed by serovars Meleagridis (2.6%, 2 isolates) and Abaetetuba (1.3%, 1 isolate). Salmonella isolates were resistant to ciprofloxacin (16.9% of isolates) and nalidixic acid (66.2% of isolates), and 68 isolates (88.3%) were multidrug resistant, displaying resistance to three or more classes of antimicrobial agents. Eighteen isolates (23.4%) had at least one plasmid-mediated quinolone resistance gene, which was identified using PCR and DNA sequencing. The most prevalent plasmid-mediated quinolone resistance gene was aac(6′)-Ib-cr, found in 14 isolates (18.2%), followed by oqxAB (9.1%) and qnrS (7.8%). Alterations in the gyrA gene were detected in 24 (57.1%) of 42 strains with a ciprofloxacin MIC of ≥0.25 μg/mL; the same level of susceptibility was found for enrofloxacin. Six types of mutations were found in the quinolone resistance determining regions of gyrA, and the predominant one (S83Y) was found singly in 15 (62.5%) of 24 isolates. We also found 22 different pulsed-field gel electrophoresis types among the Salmonella isolates. The Salmonella serovars and MICs of ciprofloxacin were similar within clusters, although individual differences were noted. This finding suggests that resistance plasmids were horizontally transmitted but also clonally spread.

scholarly journals Distribution of the Multidrug Resistance Genecfrin Staphylococcus Species Isolates from Swine Farms in China

2011 ◽  
Vol 56 (3) ◽  
pp. 1485-1490 ◽  
Author(s):  
Yang Wang ◽  
Wanjiang Zhang ◽  
Juan Wang ◽  
Congming Wu ◽  
Zhangqi Shen ◽  
...  
Keyword(s):  
Resistance Gene ◽  
Resistance Genes ◽  
Insertion Sequence ◽  
Pulsed Field Gel Electrophoresis ◽  
Content Type ◽  
Swine Farms ◽  
Different Types ◽  
Additional Resistance ◽  
Upstream Part ◽  
Staphylococcus Cohnii

ABSTRACTA total of 149 porcineStaphylococcusisolates with florfenicol MICs of ≥16 μg/ml were screened for the presence of the multiresistance genecfr, its location on plasmids, and its genetic environment. In total, 125 isolates carried eithercfr(16 isolates),fexA(92 isolates), or both genes (17 isolates). The 33cfr-carrying staphylococci, which included isolates of the speciesStaphylococcus cohnii,S. arlettae, andS. saprophyticusin which thecfrgene has not been described before, exhibited a wide variety of SmaI pulsed-field gel electrophoresis patterns. In 18 cases, thecfrgene was located on plasmids. Four different types ofcfr-carrying plasmids—pSS-01 (n= 2; 40 kb), pSS-02 (n= 3; 35.4 kb), pSS-03 (n= 10; 7.1 kb), and pBS-01 (n= 3; 16.4 kb)—were differentiated on the basis of their sizes, restriction patterns, and additional resistance genes. Sequence analysis revealed that in plasmid pSS-01, thecfrgene was flanked in the upstream part by a completeaacA-aphD-carrying Tn4001-like transposon and in the downstream part by a completefexA-carrying transposon Tn558. In plasmid pSS-02, an insertion sequence IS21-558and thecfrgene were integrated into transposon Tn558and thereby truncated thetnpAandtnpBgenes. The smallestcfr-carrying plasmid pSS-03 carried the macrolide-lincosamide-streptogramin B resistance geneerm(C). Plasmid pBS-01, previously described inBacillusspp., harbored a Tn917-like transposon, including the macrolide-lincosamide-streptogramin B resistance geneerm(B) in thecfrdownstream region. Plasmids, which in part carry additional resistance genes, seem to play an important role in the dissemination of the genecframong porcine staphylococci.

Identification and characterization of IS1476, an insertion sequence-like element that disrupts VanY function in a vancomycin-resistant Enterococcus faecium strain.

1997 ◽  
Vol 41 (8) ◽  
pp. 1805-1807 ◽  
Author(s):  
M G MacKinnon ◽  
M A Drebot ◽  
G J Tyrrell
Keyword(s):  
Resistance Gene ◽  
Enterococcus Faecium ◽  
Insertion Sequence ◽  
Vancomycin Resistant Enterococcus ◽  
Detection Strategy ◽  
Vancomycin Resistant Enterococci ◽  
Vancomycin Resistant ◽  
Identification And Characterization ◽  
Faecium Strain

The vanY gene of vancomycin-resistant enterococci encodes a D,D-carboxypeptidase. By using a PCR detection strategy, a VanA Enterococcus faecium clinical isolate was found to have an insertion sequence (IS)-like element designated IS1476 in vanY. The activity of the VanY D,D-carboxypeptidase in this isolate was decreased in a fluorometric fluoraldehyde o-phthalaldehyde assay with diacetyl-L-Lys-D-Ala-D-Ala as the substrate. This, to our knowledge, is the first report of an IS-like element in a vancomycin resistance gene.

scholarly journals BKC-2, a New BKC Variant Detected in MCR-9.1-producing Enterobacter hormaechei subsp. xiangfangensis

2020 ◽  
pp. AAC.01193-20
Author(s):  
Willames M. B. S. Martins ◽  
Evelin R. Martins ◽  
Letícia K. de Andrade ◽  
Refath Farzana ◽  
Timothy R. Walsh ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Resistance Gene ◽  
Resistance Genes ◽  
Tertiary Hospital ◽  
Multidrug Resistant ◽  
Colistin Resistance ◽  
Antimicrobial Resistance Genes ◽  
Genomic Characterization ◽  
Enterobacter Hormaechei

We performed the characterization of a multidrug-resistant (MDR) Enterobacter spp. isolate highlighting the genetic aspects of the antimicrobial resistance genes. An Enterobacter spp. isolate (Ec61) was recovered in 2014 from a transtracheal aspirate sample from a patient admitted to a Brazilian tertiary hospital and submitted to further microbiological and genomic characterization. Ec61 was identified as Enterobacter hormaechei subsp. xiangfangensis ST451, showed a MDR profile and the presence of genes codifying new β-lactamase variants, BKC-2 and ACT-84, and the mobile colistin resistance gene mcr-9.1.

scholarly journals Strain Characterization of Streptococcus suis Serotypes 28 and 31, Which Harbor the Resistance Genes optrA and ant(6)-Ia

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 213
Author(s):  
Shujie Wang ◽  
Defu Zhang ◽  
Chenggang Jiang ◽  
Haijuan He ◽  
Chenchen Cui ◽  
...  
Keyword(s):  
Resistance Gene ◽  
Glial Cells ◽  
Resistance Genes ◽  
Streptococcus Suis ◽  
Multidrug Resistant ◽  
Aminoglycoside Resistance ◽  
Strain Characterization ◽  
Infection Models ◽  
Suis Serotype

Streptococcus suis causes disease in pigs and is implicated increasingly in human disease worldwide. Although most clinical cases are associated with serotype 2, infections by other serotypes have sometimes been reported. Here, we sequenced the genome of a multidrug-resistant S. suis serotype 28 (strain 11313) and a multidrug-resistant S. suis serotype 31 (strain 11LB5). Strain 11313 was apathogenic in mouse infection models, whereas strain 11LB5 displayed ganglion demyelination, meningeal thickening, congestion, mononuclear cell infiltration, massive proliferation of cortical glial cells, and bacteria (>104 CFU/g) in the spinal cord and ganglia in mice. Furthermore, immunohistochemistry found that the heavily infiltrated glial cells were astrocytes. Strain 11313 harbored the resistance genes ant(6)-Ia, erm(B), optrA, tet(l), tet(o), and strain 11LB5 harbored the resistance genes ant(6)-Ia, erm(B), tet(40), tet(o/w/32/o), aac(6′)-aph(2″). Mouse studies showed that strain 11LB5 exhibited a similar virulence to serotype 2 strain 700794, highlighting the need for surveillance of the other serotype S. suis isolates, in addition to serotype 2, in farms. This is the first report of the aminoglycoside resistance gene ant(6)-Ia in S. suis from animals. This suggests that S. suis might serve as an antibiotic resistance reservoir, which spreads the resistance gene ant(6)-Ia or optrA to other streptococcal pathogens on farms.

scholarly journals Genotypic Characterization of Seven Strains ofMycoplasma fermentans Isolated from Synovial Fluids of Patients with Arthritis

1998 ◽  
Vol 36 (5) ◽  
pp. 1226-1231 ◽  
Author(s):  
Thierry Schaeverbeke ◽  
Maïthé Clerc ◽  
Laurence Lequen ◽  
Alain Charron ◽  
Cécile Bébéar ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Insertion Sequence ◽  
Fragment Length Polymorphism ◽  
Polymorphism Analysis ◽  
Mycoplasma Fermentans ◽  
Characterization Methods ◽  
Genotypic Characterization ◽  
Arbitrarily Primed Pcr ◽  
Reference Strains

We performed a genotypic characterization of seven strains ofMycoplasma fermentans which have been isolated from the synovial fluid of patients with rheumatoid arthritis (n = 2), spondyloarthropathy (n = 1), and unclassified arthritis (n = 4). We compared them to three reference strains (strains PG18 and K7 and incognitus strain) and to a clinical isolate from the urethra of a patient with nongonococcal urethritis. The characterization methods included electrophoresis of native DNA, arbitrarily primed PCR, and restriction fragment length polymorphism analysis following conventional and pulsed-field gel electrophoresis. Southern blot analysis with a probe internal to an insertion sequence was performed with the restriction products produced by the last two techniques. No extrachromosomal DNA sequences were detected. The M. fermentans strains identified by these methods did not present a unique profile, but they could be separated into two main categories: four articular isolates were genetically related to PG18 and the three other isolates, the urethral isolate, and the incognitus strain were related to K7. We also looked for the presence of the bacteriophage MAV1 (associated with the arthritogenic property of Mycoplasma arthritidis in rodents) in the M. fermentans strains. MAV1 DNA was not detected in either the clinical isolates or the reference strains ofM. fermentans.

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