Prevalence and characterisation of quinolone resistance mechanisms in Salmonella spp.

Development of fluoroquinolone resistance can involve several mechanisms that include chromosomal mutations in genes (gyrAB and parCE) encoding the target bacterial topoisomerase enzymes, increased expression of the AcrAB-TolC efflux system, and acquisition of transmissible quinolone-resistance genes. In this study, 176 Salmonella isolates from animals with a broad range of ciprofloxacin MICs were collected to analyze the contribution of these different mechanisms to different phenotypes. All isolates were classified according to their ciprofloxacin susceptibility pattern into five groups as follows: highly resistant (HR), resistant (R), intermediate (I), reduced susceptibility (RS), and susceptible (S). We found that the ParC T57S substitution was common in strains exhibiting lowest MICs of ciprofloxacin while increased MICs depended on the type of GyrA mutation. The ParC T57S substitution appeared to incur little cost to bacterial fitness on its own. The presence of PMQR genes represented an route for resistance development in the absence of target-site mutations. Switching of the plasmid-mediated quinolone resistance (PMQR) gene location from a plasmid to the chromosome was observed and resulted in decreased ciprofloxacin susceptibility; this also correlated with increased fitness and a stable resistance phenotype. The overexpression of AcrAB-TolC played an important role in isolates with small decreases in susceptibility and expression was upregulated by MarA more often than by RamA. This study increases our understanding of the relative importance of several resistance mechanisms in the development of fluoroquinolone resistance in Salmonella from the food chain.

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Plasmid-mediated quinolone resistance by genes qnrA1 and qnrB19 in Salmonella strains isolated in Brazil

The Journal of Infection in Developing Countries ◽

10.3855/jidc.1735 ◽

2011 ◽

Vol 5 (06) ◽

pp. 496-498 ◽

Cited By ~ 26

Author(s):

Rafaela Ferrari ◽

Antonio Galiana ◽

Rosa Cremades ◽

Juan Carlos Rodriguez ◽

Marciane Magnani ◽

...

Keyword(s):

Resistance Mechanisms ◽

Quinolone Resistance ◽

Poultry Production ◽

Salmonella Spp ◽

Mutant Selection ◽

Microbial Resistance ◽

Resistance Profile ◽

Resistant Strains ◽

Near Future ◽

Selection Of

Considering the importance of the mechanisms involved in quinolone resistance, this study evaluate the presence of PMQR in 126 epidemic and not epidemic strains of Salmonella spp. It was noted that presence of PMQR, by itself, did not generate resistance to ciprofloxacin; but detection of qnr genes in Salmonella spp. and the identification of the qnrB19 variant in a strain of poultry origin alert for the indiscriminate use of quinolones in poultry production, that can result in a pressure for mutant selection of resistant strains with a clinical limitation use of FQs in the near future. And last but not least, is the need to continued study of resistance mechanisms and to monitor the microbial resistance profile of epidemiological strains.

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Investigation of Ciprofloxacin Resistance and Its Mechanisms in Clinical Pseudomonas aeruginosa Isolates

ANKEM Dergisi ◽

10.5222/ankem.2021.022 ◽

2021 ◽

Author(s):

Nilüfer Uzunbayır Akel ◽

Yamaç Tekintaş ◽

Fethiye Ferda Yılmaz ◽

İsmail Öztürk ◽

Mustafa Ökeer ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Efflux Pump ◽

Resistance Mechanisms ◽

Regulatory Genes ◽

Quinolone Resistance ◽

University Hospital ◽

Clinical Samples ◽

Genetic Groups ◽

Ciprofloxacin Resistance ◽

Polymerase Chain

Pseudomonas aeruginosa is one of the most important causes of hospital infections. Although different antibiotic groups are used for the treatment of P.aeruginosa infections, quinolone groups are distinguished by the advantages of oral administration. However, in recent years, resistance against members of this group has made treatment more difficult. The aim of this study was to investigate the epidemiological relationship and possible mechanisms of resistance in ciprofloxacin resistant P. aeruginosa isolates from Ege University Hospital. The identification of P.aeruginosa bacteria isolated from clinical samples in Ege University Medical Faculty Medical Microbiology Laboratory was determined by VITEK MS automated systems by VITEK compact, antimicrobial susceptibility. The epidemiological relationships of the ciprofloxacin resistant isolates were determined by Enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The presence of qnrA, qnrB, qnrS, qepA genes, the quinolone resistance genes and nfxB, mexR, the regulatory genes of the efflux pump, was determined by PCR. The phenylalanine-arginine β-naphthylamide (PAβN) assay was used to determine the activation of the efflux pump. Twenty-two isolates (26.5 %) were found resistant to ciprofloxacin. According to the ERIC-PCR results, 11 unrelated clones were detected. Ciprofloxacin minimum inhibitory concentration (MIC) values were decreased 2-64 times in 10 isolates in the presence of PAIN. No ciprofloxacin MIC change was detected in one isolate. The presence of pump regulatory genes was determined in 10 of the 11 representative isolates, while only qnrB of the genes associated with quinolone resistance was detected in seven representative isolates. qnrA, qnrS, qepA genes were not detected in any isolate. Ciprofloxacin resistant P.aeruginosa isolates are isolated from our hospital. It is noteworthy that the isolates belonging to different genetic groups are in circulation in clinics. Basic resistance mechanisms are thought to be efflux pumps and qnrB genes.

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Emergence of Ciprofloxacin-Nonsusceptible Streptococcus pyogenes Isolates from Healthy Children and Pediatric Patients in Portugal

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01536-09 ◽

2010 ◽

Vol 54 (6) ◽

pp. 2677-2680 ◽

Cited By ~ 14

Author(s):

Renato Pires ◽

Carmen Ardanuy ◽

Dora Rolo ◽

Ana Morais ◽

António Brito-Avô ◽

...

Keyword(s):

Streptococcus Pyogenes ◽

Pediatric Patients ◽

Resistance Mechanisms ◽

Sequence Type ◽

Quinolone Resistance ◽

Healthy Children

ABSTRACT We describe 66 ciprofloxacin-nonsusceptible Streptococcus pyogenes isolates recovered from colonized and infected children. The ParC S79A substitution was frequent and associated with the emm6/sequence type 382 (emm6/ST382) lineage. The ParC D83G substitution was detected in two isolates (emm5/ST99 and emm28/ST52 lineages). One isolate (emm89/ST101) had no quinolone resistance-determining region codon substitutions or other resistance mechanisms. Five of 66 isolates were levofloxacin resistant. Although fluoroquinolones are not used in children, they may be putative disseminators of fluoroquinolone-nonsusceptible strains in the community.

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Quinolone resistance in Salmonella spp: veterinary pointers

The Lancet ◽

10.1016/0140-6736(90)91648-t ◽

1990 ◽

Vol 336 (8707) ◽

pp. 125 ◽

Cited By ~ 22

Author(s):

L.J.V. Piddock ◽

C. Wray ◽

I. Mcclaren ◽

Richard Wise

Keyword(s):

Quinolone Resistance ◽

Salmonella Spp

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In Vitro Activity of DX-619, a Novel Des-Fluoro(6) Quinolone, against a Panel of Streptococcus pneumoniae Mutants with Characterized Resistance Mechanisms

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.50.2.796-798.2006 ◽

2006 ◽

Vol 50 (2) ◽

pp. 796-798 ◽

Cited By ~ 4

Author(s):

Paul A. Wickman ◽

Ellen Smith Moland ◽

Jennifer A. Black ◽

Kenneth S. Thomson

Keyword(s):

Streptococcus Pneumoniae ◽

Resistance Mechanisms ◽

Quinolone Resistance ◽

Vitro Activity ◽

In Vitro Activity

ABSTRACT The in vitro activities of DX-619 and four other quinolones were compared against Streptococcus pneumoniae mutants that contained a variety of alterations within the quinolone resistance-determining regions. DX-619 was the most potent quinolone and was least affected by the mutations.

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Quinolone Resistance Mechanisms in Pneumococci

Clinical Infectious Diseases ◽

10.1086/382709 ◽

2004 ◽

Vol 38 (Supplement_4) ◽

pp. S350-S356 ◽

Cited By ~ 28

Author(s):

George M. Eliopoulos

Keyword(s):

Resistance Mechanisms ◽

Quinolone Resistance

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Antipneumococcal Activity of DK-507k, a New Quinolone, Compared with the Activities of 10 Other Agents

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.47.12.3815-3824.2003 ◽

2003 ◽

Vol 47 (12) ◽

pp. 3815-3824 ◽

Cited By ~ 11

Author(s):

Frederick A. Browne ◽

Bülent Bozdogan ◽

Catherine Clark ◽

Linda M. Kelly ◽

Lois Ednie ◽

...

Keyword(s):

Resistance Mechanisms ◽

Quinolone Resistance ◽

Penicillin G ◽

Agar Dilution ◽

Resistant Strains ◽

Resistant Mutants ◽

Subinhibitory Concentrations ◽

Time Kill

ABSTRACT Agar dilution MIC determination was used to compare the activity of DK-507k with those of ciprofloxacin, levofloxacin, gatifloxacin, moxifloxacin, sitafloxacin, amoxicillin, cefuroxime, erythromycin, azithromycin, and clarithromycin against 113 penicillin-susceptible, 81 penicillin-intermediate, and 67 penicillin-resistant pneumococci (all quinolone susceptible). DK-507k and sitafloxacin had the lowest MICs of all quinolones against quinolone-susceptible strains (MIC at which 50% of isolates were inhibited [MIC50] and MIC90 of both, 0.06 and 0.125 μg/ml, respectively), followed by moxifloxacin, gatifloxacin, levofloxacin, and ciprofloxacin. MICs of β-lactams and macrolides rose with those of penicillin G. Against 26 quinolone-resistant pneumococci with known resistance mechanisms, DK-507k and sitafloxacin were also the most active quinolones (MICs, 0.125 to 1.0 μg/ml), followed by moxifloxacin, gatifloxacin, levofloxacin, and ciprofloxacin. Mutations in quinolone resistance-determining regions of quinolone-resistant strains were in the usual regions of the parC and gyrA genes. Time-kill testing showed that both DK-507k and sitafloxacin were bactericidal against all 12 quinolone-susceptible and -resistant strains tested at twice the MIC at 24 h. Serial broth passages in subinhibitory concentrations of 10 strains for a minimum of 14 days showed that development of resistant mutants (fourfold or greater increase in the original MIC) occurred most rapidly for ciprofloxacin, followed by moxifloxacin, DK-507k, gatifloxacin, sitafloxacin, and levofloxacin. All parent strains demonstrated a fourfold or greater increase in initial MIC in<50 days. MICs of DK-507k against resistant mutants were lowest, followed by those of sitafloxacin, moxifloxacin, gatifloxacin, ciprofloxacin, and levofloxacin. Four strains were subcultured in subinhibitory concentrations of each drug for 50 days: MICs of DK-507k against resistant mutants were lowest, followed by those of sitafloxacin, moxifloxacin, gatifloxacin, levofloxacin, and ciprofloxacin. Exposure to DK-507k and sitafloxacin resulted in mutations, mostly in gyrA.

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Non-Antibiotics Strategies to Control Salmonella Infection in Poultry

Animals ◽

10.3390/ani12010102 ◽

2022 ◽

Vol 12 (1) ◽

pp. 102

Author(s):

José Martín Ruvalcaba-Gómez ◽

Zuamí Villagrán ◽

Juan José Valdez-Alarcón ◽

Marcelino Martínez-Núñez ◽

Lorena Jacqueline Gomez-Godínez ◽

...

Keyword(s):

Bacterial Infections ◽

Safety Concern ◽

Resistance Mechanisms ◽

Poultry Production ◽

Salmonella Infection ◽

Salmonella Spp ◽

In Ovo ◽

Antimicrobial Substances ◽

Health Significance ◽

Salmonella Control

Salmonella spp. is a facultative intracellular pathogen causing localized or systemic infections, involving economic and public health significance, and remains the leading pathogen of food safety concern worldwide, with poultry being the primary transmission vector. Antibiotics have been the main strategy for Salmonella control for many years, which has allowed producers to improve the growth and health of food-producing animals. However, the utilization of antibiotics has been reconsidered since bacterial pathogens have established and shared a variety of antibiotic resistance mechanisms that can quickly increase within microbial communities. The use of alternatives to antibiotics has been recommended and successfully applied in many countries, leading to the core aim of this review, focused on (1) describing the importance of Salmonella infection in poultry and the effects associated with the use of antibiotics for disease control; (2) discussing the use of feeding-based (prebiotics, probiotics, bacterial subproducts, phytobiotics) and non-feeding-based (bacteriophages, in ovo injection, vaccines) strategies in poultry production for Salmonella control; and (3) exploring the use of complementary strategies, highlighting those based on -omics tools, to assess the effects of using the available antibiotic-free alternatives and their role in lowering dependency on the existing antimicrobial substances to manage bacterial infections in poultry effectively.

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Epidemiological Study on Prevalence, Serovar Diversity, Multidrug Resistance, and CTX-M-Type Extended-Spectrum β-Lactamases of Salmonella spp. from Patients with Diarrhea, Food of Animal Origin, and Pets in Several Provinces of China

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00092-20 ◽

2020 ◽

Vol 64 (7) ◽

Author(s):

Wei Wang ◽

Li Zhao ◽

Yujie Hu ◽

Tania Dottorini ◽

Séamus Fanning ◽

...

Keyword(s):

Multidrug Resistant ◽

Quinolone Resistance ◽

Animal Origin ◽

Salmonella Spp ◽

Fecal Samples ◽

Content Type ◽

Extended Spectrum ◽

Food Of Animal Origin ◽

High Prevalence ◽

Almost All

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.

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