scholarly journals Emergence of mosaic plasmids harboring Tn1546-ermBelement inStaphylococcus aureusisolates

2018 ◽  
Author(s):  
Tsai-Wen Wan ◽  
Yu-Tzu Lin ◽  
Wei-Chun Hung ◽  
Jui-Chang Tsai ◽  
Yu-Jung Liu ◽  
...  

ABSTRACTAntimicrobial resistance inStaphylococcus aureusis a major problem and the acquisition of resistance genes may occur by horizontal gene transfer (HGT). The transposon, an important means of HGT, is recognized as a mobile genetic element that can integrate in plasmids, replicate and transfer to other strains. We have previously reported a novel structure of theEnterococcus faecium-originated Tn1546-ermBelement inS. aureus. The emergence of the Tn1546-like element is an emerging problem that requires continuous monitoring. In the present study, we expand the examination of Tn1546-ermBelement toermB-positive methicillin-susceptibleS. aureus(MSSA) (n = 116) andermB-positive methicillin-resistantS. aureus(MRSA) (n = 253) during a 16-year period, from 2000 to 2015. PCR mapping showed that 10 MSSA and 10 MRSA carried the Tn1546-ermBelement. The 10 MSSA belonged to three sequence types (ST), ST7 (n = 6), ST5 (n = 3), and ST59 (n = 1), and the 10 MRSA belonged to two STs, ST188 (n = 8) and ST965 (n = 2). Since only clonal complex 5 (including ST5, ST85, ST231, and ST371) MRSA, ST8 MRSA and ST5 MSSA have been previously reported to carry Tn1546plasmids, this is the first report describing the presence of the Tn1546-ermBelement in ST7/5/59 MSSA and ST188/965 MRSA. Plasmid sequencing revealed that the Tn1546-ermBelement was harbored by five different mosaic plasmids. In addition to resistance genes, some plasmids also harbored toxin genes.

Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 243
Author(s):  
Surawit Chueahiran ◽  
Jitrapa Yindee ◽  
Pongthai Boonkham ◽  
Nipattra Suanpairintr ◽  
Pattrarat Chanchaithong

The aim of this study was to present molecular and antimicrobial resistance characteristics of methicillin-resistant Staphylococcus aureus (MRSA) clonal complex (CC) 398 isolated from diseased dogs and cats in Thailand. A total of 20 MRSA isolates of 134 Staphylococcus aureus isolated from canine and feline clinical samples during 2017–2020 were CC398, consisting of sequence type (ST) 398 (18 isolates), ST5926 (1 isolate), and ST6563 (1 isolate) by multilocus sequence typing. spa t034 and staphylococcal cassette chromosome mec (SCCmec) V were predominantly associated with ST398. Intraclonal differentiation was present by additional spa (t1255, t4653), non-detectable spa, composite SCCmec with a hybrid of ccrA1B1+ccrC and class A mec complex, and DNA fingerprints by pulsed-field gel electrophoresis. The isolates essentially carried antimicrobial resistance genes, mediating multiple resistance to β-lactams (mecA, blaZ), tetracyclines [tet(M)], aminoglycosides [aac(6′)-Ie-aph(2′)-Ia], and trimethoprim (dfr). Livestock-associated MRSA ST398 resistance genes including lnu(B), lsa(E), spw, fexA, and tet(L) were heterogeneously found and lost in subpopulation, with the absence or presence of additional erm(A), erm(B), and ileS2 genes that corresponded to resistance phenotypes. As only a single CC398 was detected with the presence of intraclonal variation, CC398 seems to be the successful MRSA clone colonizing in small animals as a pet-associated MRSA in Thailand.


2021 ◽  
Vol 9 (4) ◽  
pp. 707
Author(s):  
J. Christopher Noone ◽  
Fabienne Antunes Ferreira ◽  
Hege Vangstein Aamot

Our culture-independent nanopore shotgun metagenomic sequencing protocol on biopsies has the potential for same-day diagnostics of orthopaedic implant-associated infections (OIAI). As OIAI are frequently caused by Staphylococcus aureus, we included S. aureus genotyping and virulence gene detection to exploit the protocol to its fullest. The aim was to evaluate S. aureus genotyping, virulence and antimicrobial resistance genes detection using the shotgun metagenomic sequencing protocol. This proof of concept study included six patients with S. aureus-associated OIAI at Akershus University Hospital, Norway. Five tissue biopsies from each patient were divided in two: (1) conventional microbiological diagnostics and genotyping, and whole genome sequencing (WGS) of S. aureus isolates; (2) shotgun metagenomic sequencing of DNA from the biopsies. Consensus sequences were analysed using spaTyper, MLST, VirulenceFinder, and ResFinder from the Center for Genomic Epidemiology (CGE). MLST was also compared using krocus. All spa-types, one CGE and four krocus MLST results matched Sanger sequencing results. Virulence gene detection matched between WGS and shotgun metagenomic sequencing. ResFinder results corresponded to resistance phenotype. S. aureus spa-typing, and identification of virulence and antimicrobial resistance genes are possible using our shotgun metagenomics protocol. MLST requires further optimization. The protocol has potential application to other species and infection types.


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.


2005 ◽  
Vol 49 (1) ◽  
pp. 470-472 ◽  
Author(s):  
Nancye C. Clark ◽  
Linda M. Weigel ◽  
Jean B. Patel ◽  
Fred C. Tenover

ABSTRACT In 2002, the first two clinical isolates of vancomycin-resistant Staphylococcus aureus (VRSA) containing vanA were recovered in Michigan and Pennsylvania. Tn1546, a mobile genetic element that encodes high-level vancomycin resistance in enterococci, was present in both isolates. With PCR and DNA sequence analysis, we compared the Tn1546 elements from each isolate to the prototype Tn1546 element. The Michigan VRSA element was identical to the prototype Tn1546 element. The Pennsylvania VRSA element showed three distinct modifications: a deletion of nucleotides 1 to 3098 at the 5′ end, which eliminated the orf1 region; an 809-bp IS1216V-like element inserted before nucleotide 3099 of Tn1546; and an inverted 1,499-bp IS1251-like element inserted into the vanSH intergenic region. These differences in the Tn1546-like elements indicate that the first two VRSA isolates were the result of independent genetic events.


2016 ◽  
Vol 60 (10) ◽  
pp. 6108-6114 ◽  
Author(s):  
Tsai-Wen Wan ◽  
Wei-Chun Hung ◽  
Jui-Chang Tsai ◽  
Yu-Tzu Lin ◽  
Hao Lee ◽  
...  

ABSTRACTWe determined the resistance determinants in 274 erythromycin-resistant methicillin-susceptibleStaphylococcus aureus(MSSA) isolates during a 13-year period, 2000 to 2012. The resistance phenotypes, inducible macrolide-lincosamide-streptogramin (iMLS), constitutive MLS (cMLS), and macrolide-streptogramin (MS) resistance phenotypes, were examined by a double-disk diffusion D test. TheermBgene was more frequent (35%; 97/274) thanermC(27%; 75/274) orermA(21%; 58/274). All 97ermB-positive isolates harbored Tn551and IS1216V. The majority (89/97) ofermB-positive isolates displayed the cMLS phenotype and carried mobile element structure (MES)-like structures, which has been previously reported in sequence type 59 (ST59) methicillin-resistantS. aureus(MRSA). The remaining 8ermB-carrying isolates, belonging to ST7 (n= 4), ST5 (n= 3), and ST59 (n= 1), weresasKintact and did not carry MES-like structures. Unlike a MES-like structure that was located on the chromosome, theermBelements onsasK-intact isolates were located on plasmids by S1 nuclease pulsed-field gel electrophoresis (PFGE) analysis and conjugation tests. Sequence data for theermB-containing region (14,566 bp) from ST59 NTUH_3874 revealed that the best match was a Tn1546-like element in plasmid pMCCL2 DNA (GenBank accession numberAP009486) ofMacrococcus caseolyticus. Tn1546is recognized as an enterococcal transposon and was known from the vancomycin resistance gene cluster in vancomycin-resistantEnterococcus(VRE). So far, acquisitions of Tn1546inS. aureushave occurred in clonal complex 5 (CC5) MRSA, but not in MSSA. This is the first report that MSSA harbors anEnterococcus faecium-originatedermB-positive Tn1546-like element located on a plasmid.


2021 ◽  
Vol 12 ◽  
Author(s):  
Nobuo Arai ◽  
Tsuyoshi Sekizuka ◽  
Yukino Tamamura-Andoh ◽  
Lisa Barco ◽  
Atsushi Hinenoya ◽  
...  

Salmonella enterica subsp. enterica serovar Typhimurium sequence type 34 (ST34) and its monophasic variant (Salmonella 4,[5],12:i:-) are among the most frequently isolated clones from both humans and animals worldwide. Our previous study demonstrated that Salmonella Typhimurium/4,[5],12:i:- strains isolated in Japan could be classified into nine clades and that clade 9 consisted of ST34 strains. In Japan, ST34/clade 9 was first found in the 1990s and has become predominant among food animals in recent years. In the present study, we analyzed the whole genome-based phylogenetic relationships and temporal information of 214 Salmonella Typhimurium/4,[5],12:i:- ST34/clade 9 strains isolated from 1998 to 2017 in Japan. The 214 strains were classified into two sublineages: the newly identified clade 9–2 diverged from clade 9 in the early 2000s and has predominated in recent years. Clonally expanding subclades in clades 9–1 or 9–2 lacked Gifsy-1 or HP1 prophages, respectively, and some strains in these subclades acquired plasmids encoding antimicrobial resistance genes. Additional genome reduction around the fljB gene encoding the phase 2-H antigen was generated by an IS26-mediated deletion adjacent to the transposon in clade 9–2. Although most of the clade 9 strains were isolated from cattle in Japan, the clonally expanding subclades in clade 9–2 (i.e., all and 24% strains of subclades 9–2a and 9–2b, respectively) were isolated from swine. The spread of clade 9 in recent years among food animals in Japan was responsible for the emergence of multiple host-adapted sublineages involving the clonally expanding subclades generated by mobile genetic element-mediated microevolution.


2021 ◽  
Author(s):  
Desiye Tesfaye Tegegne ◽  
Gezahegne Mamo ◽  
Hika Waktole ◽  
Gebrerufael Girmay

Abstract Background: Staphylococcus aureus is one of the predominant causative agents of mastitis disease in dairy herds. Mastitis disease has a negative impact in the economic losses in the dairy sector across the globe. The aims of this study were to determine the prevalence and detect antimicrobial resistance genes in the Staphylococcus aureus isolated from milk samples of subclinical bovine mastitis in Central Ethiopia.Methods: A total of 265 lactating dairy cows from various dairy farms in four different geographical locations were screened by California mastitis test (CMT) for bovine subclinical mastitis. One-hundred thirty CMT positive milk samples were collected and transported to laboratory. Different biochemical tests and polymerase chain reaction (PCR) were used for the identification of S. aureus isolates. Finally, phenotypic and genotypic methods were performed for detection of some antimicrobial resistance patterns and genes (mecA, ermA, ermC, and msrA), respectively. Results: From total of 265 lactating dairy cows screened, 49% (n=130) were positive for bovine subclinical mastitis. One-hundred thirty mastitic milk samples were subjected to bacterial culturing, one hundred (76%) S. aureus isolates were identified based on phenotypic characters. Sixty-eight confirmed S. aureus isolates were obtained using PCR. Of the sixty-eight isolates tested 12 samples were contained the methicillin resistance gene A (mecA). No amplification was observed for the erythromycin resistance genes (ermA, ermC, and msrA). Conclusion: The high resistance of Staphylococcus aureus to commonly used antimicrobials contribute in dairy farms may cause health problems in the community consuming raw milk purchased from these farms.


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