scholarly journals Molecular Analysis of a blaIMP-1-Harboring Class 3 Integron in Multidrug-Resistant Pseudomonas fulva

2018 ◽  
Vol 62 (8) ◽  
Author(s):  
Masaki Yamamoto ◽  
Yasufumi Matsumura ◽  
Ryota Gomi ◽  
Tomonari Matsuda ◽  
Satoshi Nakano ◽  
...  

ABSTRACT A multidrug-resistant (MDR) Pseudomonas fulva strain was isolated in 2006 from a urine sample. The isolate harbored the blaIMP-1 gene, which was located in a chromosomal Tn402-like class 3 integron as a gene cassette array of aacA31-fosE-blaIMP-1. Two mutations in gyrA and one mutation in parC were detected in quinolone-resistance-determining regions (QRDRs). We report a full-length, novel, blaIMP-1-carrying class 3 integron. This integron, together with mutations in QRDRs, could have influenced the MDR phenotype.

2018 ◽  
Vol 62 (9) ◽  
Author(s):  
María Pérez-Varela ◽  
Jordi Corral ◽  
Jesús Aranda ◽  
Jordi Barbé

ABSTRACTAcinetobacter baumanniihas emerged as an important multidrug-resistant nosocomial pathogen. In previous work, we identified a putative MFS transporter, AU097_RS17040, involved in the pathogenicity ofA. baumannii(M. Pérez-Varela, J. Corral, J. A. Vallejo, S. Rumbo-Feal, G. Bou, J. Aranda, and J. Barbé, Infect Immun 85:e00327-17, 2017,https://doi.org/10.1128/IAI.00327-17). In this study, we analyzed the susceptibility to diverse antimicrobial agents ofA. baumanniicells defective in this transporter, referred to as AbaQ. Our results showed that AbaQ is mainly involved in the extrusion of quinolone-type drugs inA. baumannii.


2017 ◽  
Vol 62 (1) ◽  
Author(s):  
Manoon Leechawengwongs ◽  
Therdsak Prammananan ◽  
Sarinya Jaitrong ◽  
Pamaree Billamas ◽  
Nampueng Makhao ◽  
...  

ABSTRACT New fluoroquinolones (FQs) have been shown to be more active against drug-resistant Mycobacterium tuberculosis strains than early FQs, such as ofloxacin. Sitafloxacin (STFX) is a new fluoroquinolone with in vitro activity against a broad range of bacteria, including M. tuberculosis. This study aimed to determine the in vitro activity of STFX against all groups of drug-resistant strains, including multidrug-resistant M. tuberculosis (MDR M. tuberculosis), MDR M. tuberculosis with quinolone resistance (pre-XDR), and extensively drug-resistant (XDR) strains. A total of 374 drug-resistant M. tuberculosis strains were tested for drug susceptibility by the conventional proportion method, and 95 strains were randomly submitted for MIC determination using the microplate alamarBlue assay (MABA). The results revealed that all the drug-resistant strains were susceptible to STFX at a critical concentration of 2 μg/ml. Determination of the MIC90s of the strains showed different MIC levels; MDR M. tuberculosis strains had a MIC90 of 0.0625 μg/ml, whereas pre-XDR and XDR M. tuberculosis strains had identical MIC90s of 0.5 μg/ml. Common mutations within the quinolone resistance-determining region (QRDR) of gyrA and/or gyrB did not confer resistance to STFX, except that double mutations of GyrA at Ala90Val and Asp94Ala were found in strains with a MIC of 1.0 μg/ml. The results indicated that STFX had potent in vitro activity against all the groups of drug-resistant M. tuberculosis strains and should be considered a new repurposed drug for treatment of multidrug-resistant and extensively drug-resistant TB.


2020 ◽  
Vol 64 (7) ◽  
Author(s):  
Wei Wang ◽  
Li Zhao ◽  
Yujie Hu ◽  
Tania Dottorini ◽  
Séamus Fanning ◽  
...  

ABSTRACT A total of 2,283 Salmonella isolates were recovered from 18,334 samples, including samples from patients with diarrhea, food of animal origin, and pets, across 5 provinces of China. The highest prevalence of Salmonella spp. was detected in chicken meats (39.3%, 486/1,237). Fifteen serogroups and 66 serovars were identified, with Salmonella enterica serovars Typhimurium and Enteritidis being the most dominant. Most (85.5%, 1,952/2,283) isolates exhibited resistance to ≥1 antimicrobial, and 56.4% were multidrug resistant (MDR). A total of 222 isolates harbored extended-spectrum β-lactamases (ESBLs), and 200 of these were of the CTX-M type and were mostly detected in isolates from chicken meat and turtle fecal samples. Overall, eight blaCTX-M genes were identified, with blaCTX-M-65, blaCTX-M-123, blaCTX-M-14, blaCTX-M-79, and blaCTX-M-130 being the most prevalent. In total, 166 of the 222 ESBL-producing isolates had amino acid substitutions in GyrA (S83Y, S83F, D87G, D87N, and D87Y) and ParC (S80I), while the plasmid-mediated quinolone resistance (PMQR)-encoding genes oqxA, oqxB, qepA, qnrB, and qnrS were detected in almost all isolates. Of the 15 sequence types (STs) identified in the 222 ESBLs, ST17, ST11, ST34, and ST26 ranked among the top 5 in number of isolates. Our study revealed considerable serovar diversity and a high prevalence of the co-occurrence of MDR determinants, including CTX-M-type ESBLs, quinolone resistance-determining region (QRDR) mutations, and PMQR genes. This is the first report of CTX-M-130 Salmonella spp. from patients with diarrhea and QRDR mutations from turtle fecal samples. Our study emphasizes the importance of actions, both in health care settings and in the veterinary medicine sector, to control the dissemination of MDR, especially the CTX-M-type ESBL-harboring Salmonella isolates.


2015 ◽  
Vol 59 (5) ◽  
pp. 2678-2687 ◽  
Author(s):  
Wataru Shimizu ◽  
Shizuo Kayama ◽  
Shuntaro Kouda ◽  
Yoshitoshi Ogura ◽  
Kanao Kobayashi ◽  
...  

ABSTRACTA 9-year surveillance for multidrug-resistant (MDR)Pseudomonas aeruginosain the Hiroshima region showed that the number of isolates harboring the metallo-β-lactamase geneblaIMP-1abruptly increased after 2004, recorded the highest peak in 2006, and showed a tendency to decline afterwards, indicating a history of an epidemic. PCR mapping of the variable regions of the integrons showed that this epidemic was caused by the clonal persistence and propagation of an MDRP. aeruginosastrain harboring theblaIMP-1gene and an aminoglycoside 6′-N-acetyltransferase gene,aac(6′)-Iaein a class I integron (In113), whose integrase geneintl1was disrupted by an IS26insertion. Sequence analysis of the representative strain PA058447 resistance element containing the In113-derived gene cassette array showed that the element forms an IS26transposon embedded in the chromosome. It has a Tn21backbone and is composed of two segments sandwiched by three IS26s. In Japan, clonal nationwide expansion of an MDRP. aeruginosaNCGM2.S1 harboring chromosomally encoded In113 with intactintl1is reported. Multilocus sequence typing and genomic comparison strongly suggest that PA058447 and NCGM2.S1 belong to the same clonal lineage. Moreover, the structures of the resistance element in the two strains are very similar, but the sites of insertion into the chromosome are different. Based on tagging information of the IS26present in both resistance elements, we suggest that the MDRP. aeruginosaclone causing the epidemic in Hiroshima for the past 9 years originated from a common ancestor genome of PA058447 and NCGM2.S1 through an IS26insertion intointl1of In113 and through IS26-mediated genomic rearrangements.


2011 ◽  
Vol 77 (20) ◽  
pp. 7121-7127 ◽  
Author(s):  
Maria Karczmarczyk ◽  
Ciara Walsh ◽  
Rosemarie Slowey ◽  
Nola Leonard ◽  
Séamus Fanning

ABSTRACTThis study describes the genotypic characteristics of a collection of 100 multidrug-resistant (MDR)Escherichia colistrains recovered from cattle and the farm environment in Ireland in 2007. The most prevalent antimicrobial resistance identified was to streptomycin (100%), followed by tetracycline (99%), sulfonamides (98%), ampicillin (82%), and neomycin (62%). Resistance was mediated predominantly bystrA-strB(92%),tetA(67%),sul2(90%),blaTEM(79%), andaphA1(63%) gene markers, respectively. Twenty-seven isolates harbored a class 1 integrase (intI1), whileqacEΔ1andsul1markers were identified in 25 and 26 isolates, respectively. The variable regions of these integrons contained aminoglycoside, trimethoprim, and β-lactam resistance determinants (aadA12,aadB-aadA1,blaOXA-30-aadA1,dfrA1-aadA1,dfrA7). Class 2 integrons were identified less frequently (4%) and contained the gene cassette arraydfrA1-sat1-aadA1. Resistance to ampicillin, neomycin, streptomycin, sulfonamide, and tetracycline was associated with transferable high-molecular-weight plasmids, as demonstrated by conjugation assays. A panel of virulence markers was screened for by PCR, and genes identified includedvt1, K5 in 2 isolates,papCin 10 isolates, and PAI IV536in 37 isolates. MDR commensalE. coliisolates from Irish cattle displayed considerable diversity with respect to the genes identified. Our findings highlight the importance of the commensal microflora of food-producing animals as a reservoir of transferable MDR.


2013 ◽  
Vol 58 (1) ◽  
pp. 596-598 ◽  
Author(s):  
Lalitagauri M. Deshpande ◽  
Ronald N. Jones ◽  
Leah N. Woosley ◽  
Mariana Castanheira

ABSTRACTAmong 220 clinical isolates of Gram-negative bacilli collected in India during 2000, 22 strains showing elevated imipenem MICs were evaluated for carbapenemase production. One DIM-1-producingPseudomonas stutzeriisolate was detected, and no other carbapenemase-encoding genes were identified. This detection of a DIM-1-producingP. stutzeriisolate from India predating the finding of this gene in the index Dutch strain and the very recent detection of DIM-1 in Africa suggest an unidentified environmental source of this metallo-β-lactamase gene.


2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Mihnea R. Mangalea ◽  
Emily K. Luna ◽  
Janet Ziegle ◽  
Christine Chang ◽  
Angela M. Bosco-Lauth ◽  
...  

Pandoraea pnomenusa strain TF-18 was isolated from the roots of rice seedlings on selective medium containing four classes of antibiotics for isolation of Burkholderia pseudomallei. Using Pacific Biosciences (PacBio) single-molecule real-time (SMRT) sequencing technology, we report here a complete genome of 5,499,432 bases, a GC content of 64.8%, and 4,849 coding sequences.


2018 ◽  
Vol 62 (8) ◽  
Author(s):  
Zhaojing Zong ◽  
Wei Jing ◽  
Jin Shi ◽  
Shu'an Wen ◽  
Tingting Zhang ◽  
...  

ABSTRACT Oxazolidinones are efficacious in treating mycobacterial infections, including tuberculosis (TB) caused by drug-resistant Mycobacterium tuberculosis. In this study, we compared the in vitro activities and MIC distributions of delpazolid, a novel oxazolidinone, and linezolid against multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) in China. Additionally, genetic mutations in 23S rRNA, rplC, and rplD genes were analyzed to reveal potential mechanisms underlying the observed oxazolidinone resistance. A total of 240 M. tuberculosis isolates were included in this study, including 120 MDR-TB isolates and 120 XDR-TB isolates. Overall, linezolid and delpazolid MIC90 values for M. tuberculosis isolates were 0.25 mg/liter and 0.5 mg/liter, respectively. Based on visual inspection, we tentatively set epidemiological cutoff (ECOFF) values for MIC determinations for linezolid and delpazolid at 1.0 mg/liter and 2.0 mg/liter, respectively. Although no significant difference in resistance rates was observed between linezolid and delpazolid among XDR-TB isolates (P > 0.05), statistical analysis revealed a significantly greater proportion of linezolid-resistant isolates than delpazolid-resistant isolates within the MDR-TB group (P = 0.036). Seven (53.85%) of 13 linezolid-resistant isolates were found to harbor mutations within the three target genes. Additionally, 1 isolate exhibited an amino acid substitution (Arg126His) within the protein encoded by rplD that contributed to high-level resistance to linezolid (MIC of >16 mg/liter), compared to a delpazolid MIC of 0.25. In conclusion, in vitro susceptibility testing revealed that delpazolid antibacterial activity was comparable to that of linezolid. A novel mutation within rplD that endowed M. tuberculosis with linezolid, but not delpazolid, resistance was identified.


2011 ◽  
Vol 55 (11) ◽  
pp. 5262-5266 ◽  
Author(s):  
Sophie A. Granier ◽  
Laura Hidalgo ◽  
Alvaro San Millan ◽  
Jose Antonio Escudero ◽  
Belen Gutierrez ◽  
...  

ABSTRACTThe 16S rRNA methyltransferase ArmA is a worldwide emerging determinant that confers high-level resistance to most clinically relevant aminoglycosides. We report here the identification and characterization of a multidrug-resistantSalmonella entericasubspecies I.4,12:i:− isolate recovered from chicken meat sampled in a supermarket on February 2009 in La Reunion, a French island in the Indian Ocean. Susceptibility testing showed an unusually high-level resistance to gentamicin, as well as to ampicillin, expanded-spectrum cephalosporins and amoxicillin-clavulanate. Molecular analysis of the 16S rRNA methyltransferases revealed presence of thearmAgene, together withblaTEM-1,blaCMY-2, andblaCTX-M-3. All of these genes could be transferreden blocthrough conjugation intoEscherichia coliat a frequency of 10−5CFU/donor. Replicon typing and S1 pulsed-field gel electrophoresis revealed that thearmAgene was borne on an ∼150-kb broad-host-range IncP plasmid, pB1010. To elucidate howarmAhad integrated in pB1010, a PCR mapping strategy was developed for Tn1548, the genetic platform forarmA.The gene was embedded in a Tn1548-like structure, albeit with a deletion of the macrolide resistance genes, and an IS26was inserted within themelgene. To our knowledge, this is the first report of ArmA methyltransferase in food, showing a novel route of transmission for this resistance determinant. Further surveillance in food-borne bacteria will be crucial to determine the role of food in the spread of 16S rRNA methyltransferase genes worldwide.


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