Antibiotic resistance, virulence factors and biofilm formation ability inEscherichia colistrains isolated from chicken meat and wildlife in the Czech Republic

2017 ◽  
Vol 52 (8) ◽  
pp. 570-576 ◽  
Author(s):  
Silvie Pavlickova ◽  
Anja Klancnik ◽  
Magda Dolezalova ◽  
Sonja Smole Mozina ◽  
Ivan Holko
Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 170
Author(s):  
Angela França ◽  
Vânia Gaio ◽  
Nathalie Lopes ◽  
Luís D. R. Melo

Coagulase-negative staphylococci (CoNS) have emerged as major pathogens in healthcare-associated facilities, being S. epidermidis, S. haemolyticus and, more recently, S. lugdunensis, the most clinically relevant species. Despite being less virulent than the well-studied pathogen S. aureus, the number of CoNS strains sequenced is constantly increasing and, with that, the number of virulence factors identified in those strains. In this regard, biofilm formation is considered the most important. Besides virulence factors, the presence of several antibiotic-resistance genes identified in CoNS is worrisome and makes treatment very challenging. In this review, we analyzed the different aspects involved in CoNS virulence and their impact on health and food.


2019 ◽  
Vol 85 (22) ◽  
Author(s):  
Abigail L. Manson ◽  
Daria Van Tyne ◽  
Timothy J. Straub ◽  
Sarah Clock ◽  
Michael Crupain ◽  
...  

ABSTRACT Industrial farms are unique, human-created ecosystems that provide the perfect setting for the development and dissemination of antibiotic resistance. Agricultural antibiotic use amplifies naturally occurring resistance mechanisms from soil ecologies, promoting their spread and sharing with other bacteria, including those poised to become endemic within hospital environments. To better understand the role of enterococci in the movement of antibiotic resistance from farm to table to clinic, we characterized over 300 isolates of Enterococcus cultured from raw chicken meat purchased at U.S. supermarkets by the Consumers Union in 2013. Enterococcus faecalis and Enterococcus faecium were the predominant species found, and antimicrobial susceptibility testing uncovered striking levels of resistance to medically important antibiotic classes, particularly from classes approved by the FDA for use in animal production. While nearly all isolates were resistant to at least one drug, bacteria from meat labeled as raised without antibiotics had fewer resistances, particularly for E. faecium. Whole-genome sequencing of 92 isolates revealed that both commensal- and clinical-isolate-like enterococcal strains were associated with chicken meat, including isolates bearing important resistance-conferring elements and virulence factors. The ability of enterococci to persist in the food system positions them as vehicles to move resistance genes from the industrial farm ecosystem into more human-proximal ecologies. IMPORTANCE Bacteria that contaminate food can serve as a conduit for moving drug resistance genes from farm to table to clinic. Our results show that chicken meat-associated isolates of Enterococcus are often multidrug resistant, closely related to pathogenic lineages, and harbor worrisome virulence factors. These drug-resistant agricultural isolates could thus represent important stepping stones in the evolution of enterococci into drug-resistant human pathogens. Although significant efforts have been made over the past few years to reduce the agricultural use of antibiotics, continued assessment of agricultural practices, including the roles of processing plants, shared breeding flocks, and probiotics as sources for resistance spread, is needed in order to slow the evolution of antibiotic resistance. Because antibiotic resistance is a global problem, global policies are needed to address this threat. Additional measures must be taken to mitigate the development and spread of antibiotic resistance elements from farms to clinics throughout the world.


2021 ◽  
Vol 30 (2) ◽  
pp. 9-14
Author(s):  
Yasser M. Ismail ◽  
Sahar M. Fayed ◽  
Aliaa H. Wehedy

Background: P.aeruginosa has many virulence factors which are the main reason for infection and the emergence of antibiotic resistance leading to an increase of morbidity and mortality. Currently, multidrug resistance is the hardest problem, which made it imperative to search for alternative treatment strategies. Objective: detection of some phenotypic virulence factors of P.aeruginosa isolated from ICU patients and the possibility of any antibiotic resistance related to certain virulence factors released by P. aeruginosa. Methodology: Our study was carried out on patients admitted to ICU Department in Benha University Hospital and infected with P.aeruginosa, the isolates subjected to phenotypic detection of the virulence factors: phospholipase, alkaline protease, lipase, gelatinase, esculin hydrolysis, biofilm formation, hemolysin and DNase production using specific media for each and evaluation of the antibiotic susceptability pattern using Kirby Bauer disk diffusion assay. Results: P.aeruginosa virulence factors were recorded as follow: hemolysin (70%) followed by alkaline protease (68%), phospholipase (62%), gelatinase & biofilm formation (60%) for each, lipase & bile esculin hydrolysis (54%) for each and DNase (2%).High antibiotic resistance was detected to mostly all of the used antibiotic discs. Also, presence of invasive device, prolonged hospital stay, ICU stay and higher number of virulence factors were associated with poor outcome. Conclusions: Production of different phenotypic virulence factors in high amount reflects their important role in spread of infection and pathogenicity with increased antibiotic resistance. Therefore finding anti-virulence factors as adjuvant therapy has an important role in treatment of P. aeruginosa especially MDR isolates.


2020 ◽  
Vol 88 (10) ◽  
Author(s):  
Feiruz Alamiri ◽  
Yashuan Chao ◽  
Maria Baumgarten ◽  
Kristian Riesbeck ◽  
Anders P. Hakansson

ABSTRACT Biofilm formation by Streptococcus pyogenes (group A streptococcus [GAS]) in model systems mimicking the respiratory tract is poorly documented. Most studies have been conducted on abiotic surfaces, which poorly represent human tissues. We have previously shown that GAS forms mature and antibiotic-resistant biofilms on physiologically relevant epithelial cells. However, the roles of the substratum, extracellular matrix (ECM) components, and GAS virulence factors in biofilm formation and structure are unclear. In this study, biofilm formation was measured on respiratory epithelial cells and keratinocytes by determining biomass and antibiotic resistance, and biofilm morphology was visualized using scanning electron microscopy. All GAS isolates tested formed biofilms that had similar, albeit not identical, biomass and antibiotic resistance for both cell types. Interestingly, functionally mature biofilms formed more rapidly on keratinocytes but were structurally denser and coated with more ECM on respiratory epithelial cells. The ECM was crucial for biofilm integrity, as protein- and DNA-degrading enzymes induced bacterial release from biofilms. Abiotic surfaces supported biofilm formation, but these biofilms were structurally less dense and organized. No major role for M protein, capsule, or streptolysin O was observed in biofilm formation on epithelial cells, although some morphological differences were detected. NAD-glycohydrolase was required for optimal biofilm formation, whereas streptolysin S and cysteine protease SpeB impaired this process. Finally, no correlation was found between cell adherence or autoaggregation and GAS biofilm formation. Combined, these results provide a better understanding of the role of biofilm formation in GAS pathogenesis and can potentially provide novel targets for future treatments against GAS infections.


Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 130
Author(s):  
Magdalena Ratajczak ◽  
Dorota Kaminska ◽  
Jolanta Dlugaszewska ◽  
Marzena Gajecka

The spread of bacterial resistance to antibiotics affects various areas of life. The aim of this study was to assess the occurrence of Pseudomonas aeruginosa, and other bacteria mainly from orders Enterobacterales and Staphylococcus in the pharmaceutical production sites, and to characterize isolated strains in the aspects of antibiotic resistance, biofilm formation, and presence of genes encoding virulence factors. Genes encoding selected virulence factors were detected using PCR techniques. Antimicrobial susceptibility testing was applied in accordance with the EUCAST recommendations. A total of 46 P. aeruginosa strains were isolated and 85% strains showed a strong biofilm-forming ability. The qualitative identification of genes taking part in Quorum Sensing system demonstrated that over 89% of strains contained lasR and rhlI genes. An antimicrobial susceptibility testing revealed nine strains resistant to at least one antibiotic, and two isolates were the metallo-β-lactamase producers. Moreover, the majority of P. aeruginosa strains contained genes encoding various virulence factors. Presence of even low level of pathogenic microorganisms or higher level of opportunistic pathogens and their toxic metabolites might result in the production inefficiency. Therefore, the prevention of microbial contamination, effectiveness of sanitary and hygienic applied protocols, and constant microbiological monitoring of the environment are of great importance.


2017 ◽  
Vol 86 (2) ◽  
pp. 167-174 ◽  
Author(s):  
Vladimir Pyatov ◽  
Irena Vrtková ◽  
Aleš Knoll

The aim of this research was to develop multiplex polymerase chain reaction assays for the detection of aminoglycoside (strA, strB), sulphonamide (sulI, sulII), tetracycline (tetA, tetB, tetK, tetM, tetO), macrolide and lincosamide (msrA, ermA, ermB, ermC, mefA/E) genes of resistance in mastitis pathogens (Escherichia coli, Staphylococcus aureus, Streptococcus uberis, Streptococcus agalactiae and Streptococcus dysgalactiae). Applying the established assays, we investigated the distribution of antibiotic resistance genes in the above mentioned species isolated from milk samples in the Czech Republic. Each assay consisted of seven pairs of primers. Six of them amplified fragments of antibiotic resistance genes and one pair a fragment of a species specific gene. Polymerase chain reaction conditions were optimized to amplify seven gene fragments simultaneously in one reaction. In total, 249 isolates were used, among which 111 were positive for E. coli, 52 for S. aureus and 86 for Streptococcus spp. The majority (60.2%) of bacteria carried at least one antibiotic resistance gene and 44.6% were multidrug-resistant. The designed multiplex polymerase chain reaction assays may be applied as diagnostic method to replace or complement standard techniques of antibiotic susceptibility testing in the mentioned pathogens.


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