Although Campylobacter jejuni is the pathogen responsible for the most common foodborne illness, tracing of the infection source remains challenging due to its highly variable genome. Therefore, one of the aim of the study was to compare three genotyping methods (MLST, PFGE, and mP-BIT) to determine the most effective genotyping tool. C. jejuni strains were divided into 4 clusters based on strain similarity in the cgMLST dendrogram. Subsequently, the dendrograms of the 3 tested methods were compared to determine the accuracy of each method compared to the reference cgMLST method. Moreover, a cost-benefit analysis has showed that MLST had the highest inverse discrimination index (97%) and required less workflow, time, fewer consumables, and low bacterial sample quantity. PFGE was shown to be obsolete both because of its low discriminatory power and the complexity of the procedure. Similarly, mP‐BIT showed low separation results, which was compensated by its high availability. Therefore, our data showed that MLST is the optimal tool for genotyping C. jejuni. Another aim was to compare the antimicrobial resistance to ciprofloxacin, erythromycin, and tetracycline in C. jejuni strains isolated from human, water, air, food, and animal samples by two gene sequence-based prediction methods and to compare them with the actual susceptibility of C. jejuni strains using the disc diffusion method. Both tools, ResFinder and RGI, synchronously predict the antimicrobial susceptibility of C. jejuni and either can be used.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální léková rezistence genetika MeSH
- Campylobacter jejuni * genetika MeSH
- genotyp MeSH
- kampylobakterové infekce * mikrobiologie MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- multilokusová sekvenční typizace MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
High resistance to environmental factors as well as the ability to form biofilms allow Listeria monocytogenes to persist for a long time in difficult-to-reach places in food-producing plants. L. monocytogenes enters final products from contaminated surfaces in different areas of plants and poses a health risk to consumer. Modified surfaces are already used in the food industry to prevent cross-contamination. In this study, stainless-steel surfaces were coated with nanoscale silicon dioxide and the effects on attachment, bacterial growth and detachment of L. monocytogenes were evaluated. Attachment was considered for three different ways of application to simulate different scenarios of contamination. Bacterial growth of L. monocytogenes on the surface was recorded over a period of up to 8 h. Detachment was tested after cleaning inoculated stainless-steel surfaces with heated distilled water or detergent. Coating stainless-steel surfaces with nanoscale silica tends to reduce adherence and increased detachment and does not influence the bacterial growth of L. monocytogenes. Further modifications of the coating are necessary for a targeted use in the reduction of L. monocytogenes in food-processing plants.
Despite numerous studies on Escherichia coli (E. coli) from sheep, there have been few reports on the characterization of E. coli isolates from various organs of individual sheep until now. The present study conducted molecular typing, antibiotics resistance, biofilm formation, and virulence genes on E. coli isolated from 57 freshly slaughtered apparently healthy sheep carcasses, gallbladders, fecal samples, and mesenteric lymph nodes (MLNs). The results demonstrated that the detection rate of R1 LPS core type in E. coli isolated from fecal samples (70.83%) was higher than that from other organs, but the detection rate of antibiotic resistance genes was lower (P < 0.05). The predominant phylogenetic group of E. coli isolated from the carcasses was group B1 (93.33%), and the detection rate of multidrug-resistance phenotype (80%) and the resistance rate of E. coli was higher than that from other organs (P < 0.05). Interestingly, the intensity of biofilm formation of E. coli isolated from MLNs was higher than that from other organs (P < 0.05). However, except for ibeB, the detection rates of virulence genes did not differ in E.coli isolated from different organs. In conclusion, differences were noted in these parameters of E. coli isolated from different organs of individual sheep. Therefore, the data may contain considerable mistakes concerning the actual situation in the host if we only analyze the data of E. coli isolated from feces or carcasses.
- MeSH
- antibakteriální látky * farmakologie MeSH
- bakteriální léková rezistence genetika MeSH
- biofilmy * růst a vývoj účinky léků MeSH
- Escherichia coli * genetika účinky léků izolace a purifikace klasifikace fyziologie MeSH
- faktory virulence * genetika MeSH
- feces mikrobiologie MeSH
- fylogeneze MeSH
- infekce vyvolané Escherichia coli mikrobiologie veterinární MeSH
- molekulární typizace MeSH
- nemoci ovcí mikrobiologie MeSH
- ovce MeSH
- virulence genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Extracelulární vezikuly (EV) jsou transportní váčky derivované ze zdrojové buňky do extracelulárního prostředí. Představují nový pilíř mezibuněčné komunikace, neboť přenáší nukleové kyseliny, proteiny a různé signální molekuly, které jsou chráněny před degradací v extracelulárním prostředí a posléze jsou uvolněny fúzí vezikuly s cílovou buňkou. Transportní mechanismus je zajištěn povrchovými strukturami účastnícími se buněčné adheze. Je všeobecně známé, že všechny buněčné organismy jsou schopné tvořit EV. Většina lidských buněk je schopna produkovat EV, díky tomu je možná jejich detekce ve všech tělesných kompartmentech. EV při svém objevu byly vnímány jako nepotřebné odpadní váčky a stály na okraji zájmů. Zásluhou nově popsaným mechanismům transportu biologicky aktivních molekul je známo, že se EV účastní celé řady homeostatických mechanismů. V infekčním lékařství je nejvíce studována oblast modulace imunitní odpovědi, kdy jsou vnímány jako potenciální biomarkery, neboť jejich produkce či nesený obsah může být alterován za patologických stavů. U mikrobů stojí v popředí interakce na úrovni patogen-patogen a patogen-hostitel. Další možností je potenciální využití EV jako transportních lékových systémů a nových cílů farmakoterapie.
Extracellular vesicles (EVs) are mother cell derived transport units released into the extracellular environment. They are a new pillar of intercellular communication as they carry nucleic acids, proteins, and other signalling molecules, protecting them from degradation in the extracellular environment until fusion of the vesicle with the target cell. The transport mechanism relies on surface structures involved in cell adhesion. It is well known that all cellular organisms are capable of producing EVs. Most human cells have this capability, and EVs can be detected in all body compartments. At the time of their discovery, EVs were considered as useless waste vesicles of marginal interest. Thanks to the newly described transport mechanisms of biologically active molecules, EVs are currently known to participate in a variety of homeostatic mechanisms. In infectious diseases, the most studied area is the modulation of the immune response, where they are seen as potential biomarkers, as their production or the content they carry can be altered under pathological conditions. For microbes, interactions at the pathogen-pathogen and pathogen-host level are at the forefront of attention. EVs also have potential for use as drug delivery systems and novel targets for pharmacotherapy.
- MeSH
- biologické markery metabolismus MeSH
- exozómy klasifikace mikrobiologie MeSH
- extracelulární vezikuly * fyziologie klasifikace mikrobiologie MeSH
- fyziologie bakterií MeSH
- fyziologie virů MeSH
- mezibuněčná komunikace genetika MeSH
- transportní vezikuly fyziologie klasifikace mikrobiologie MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
Crossing of interspecies barriers by microorganisms is observed. In recent years, Staphylococcus pseudintermedius-a species formerly thought to be animal-has also been isolated from human clinical materials. Many virulence factors are responsible for the colonization, which is the first step an infection, of the new host organism. We analyzed the factors influencing this colonization as well as susceptibility to antibiotics in fourteen S. pseudintermedius strains isolated from clinical cases from humans and animals. The occurrence of genes responsible for binding elastin, fibronectin, and fibrinogen and some phenotypic features, although different between strains, is comparable in both groups. However, the animal isolates had more genes coding for virulence factors. All isolates tested had the exfoliating toxin gene and the leukotoxin determining genes, but only the human strains had enterotoxin genes. The assessment of antibiotic resistance of strains of both groups indicates their broad resistance to antibiotics commonly used in veterinary medicine. Antibiotic resistance was more common among animal isolates. The multilocus sequence typing analysis of the studied strains was performed. The results indicated a large diversity of the S. pseudintermedius population in both studied groups of strains. Equipped with important virulence factors, they showed the ability to infect animals and humans. The clonal differentiation of the methicillin-susceptible strains and the multidrug resistance of the strains of both studied groups should be emphasized. The considerable genetic diversity of strains from a limited geographical area indicates the processes of change taking place within this species. Thus, careful observation of the ongoing process of variation is necessary, as they may lead to the selection of S. pseudintermedius, which will pose a significant threat to humans.
Staphylococcus aureus is one of the most common bacterial pathogens, often asymptomatically colonizing healthy people, but capable of causing fatal disease. The ability to treat S. aureus infections is limited by the rapid spread of multidrug-resistant strains. This study aimed to determine the prevalence of S. aureus carriage among students from Okada, Edo State, Nigeria, to analyze the antibiotic resistance patterns and molecular characteristics of S. aureus isolates. One hundred healthy students from Okada, Nigeria, were tested for nasal colonization by S. aureus. Isolates were identified using standard microbiological methods. The susceptibilities of the isolates to a panel of 22 antimicrobials were tested. spa and staphylococcal cassette chromosome mec typing were performed. The prevalence of S. aureus and methicillin-resistant S. aureus (MRSA) among the students was 23% and 6%, respectively. Of the six (26.1%; 6/23) MRSA isolates detected, CC88-MRSA-IVa (n = 2) and CC7-MRSA-V (n = 2) were the most frequent clones. The CC7-MRSA-V isolates were resistant to multiple antimicrobials. Overall, resistance to beta-lactams, tetracyclines, fluoroquinolones, and aminoglycosides was detected among the S. aureus and MRSA isolates. The high prevalence of MRSA and methicillin-susceptible isolates with resistance to multiple antimicrobial classes observed among the students is an alarming finding. This study indicated the circulation of resistant clones of S. aureus in Nigerian educational institutions and the community.
- MeSH
- antibakteriální látky farmakologie MeSH
- lidé MeSH
- methicilin rezistentní Staphylococcus aureus * MeSH
- mikrobiální testy citlivosti MeSH
- rezistence na methicilin MeSH
- stafylokokové infekce * farmakoterapie epidemiologie mikrobiologie MeSH
- Staphylococcus aureus MeSH
- studenti MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Nigérie MeSH
Antimicrobial resistance is well-known to be a global health and development threat. Due to the decrease of effective antimicrobials, re-evaluation in clinical practice of old antibiotics, as fosfomycin (FOS), have been necessary. FOS is a phosphonic acid derivate that regained interest in clinical practice for the treatment of complicated infection by multi-drug resistant (MDR) bacteria. Globally, FOS resistant Gram-negative pathogens are raising, affecting the public health, and compromising the use of the antibiotic. In particular, the increased prevalence of FOS resistance (FOSR) profiles among Enterobacterales family is concerning. Decrease in FOS effectiveness can be caused by i) alteration of FOS influx inside bacterial cell or ii) acquiring antimicrobial resistance genes. In this review, we investigate the main components implicated in FOS flow and report specific mutations that affect FOS influx inside bacterial cell and, thus, its effectiveness. FosA enzymes were identified in 1980 from Serratia marcescens but only in recent years the scientific community has started studying their spread. We summarize the global epidemiology of FosA/C2/L1-2 enzymes among Enterobacterales family. To date, 11 different variants of FosA have been reported globally. Among acquired mechanisms, FosA3 is the most spread variant in Enterobacterales, followed by FosA7 and FosA5. Based on recently published studies, we clarify and represent the molecular and genetic composition of fosA/C2 genes enviroment, analyzing the mechanisms by which such genes are slowly transmitting in emerging and high-risk clones, such as E. coli ST69 and ST131, and K. pneumoniae ST11. FOS is indicated as first line option against uncomplicated urinary tract infections and shows remarkable qualities in combination with other antibiotics. A rapid and accurate identification of FOSR type in Enterobacterales is difficult to achieve due to the lack of commercial phenotypic susceptibility tests and of rapid systems for MIC detection.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální léková rezistence genetika MeSH
- Escherichia coli genetika MeSH
- fosfomycin * farmakologie MeSH
- Klebsiella pneumoniae genetika MeSH
- proteiny z Escherichia coli * genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
A total of, 78 Clostridium septicum (CLSE) isolates were screened for genes encoding: α-toxin, flagellin, and resistance to vancomycin (VANg). The isolates were also tested for their ability to form biofilm and their antibiotic susceptibility. All isolates were positive for α-toxin and flagellin genes. However, only 19 isolates (24.3%) showed prevalence for VANg. We observed the strongest capacity to form a biofilm (100%) in isolates from patients with oncologic or septic and febrile diagnoses. This percentage was also very high in patients with colitis and gastrointestinal hemorrhage (72.7%). No less than 43 isolates showed antibiotic resistance, and 21 were multidrug-resistant (MDR). Interestingly, our studies showed a correlation between antibiotic resistance and biofilm formation. A statistically significant difference was observed between biofilm-forming MDR isolates and those with low/no biofilm-forming ability. However, the most impressive observation was the correlation with mortality rate. While the overall mortality rate for CLSE infections was 16.7% (13/78), the mortality rate for patients infected with MDR isolates forming biofilm moderately or strongly reached 38.1% (8/21). This number increased even further when only infections with the biofilm-forming VANg-positive isolates were considered (61.5%; 8/13). Therefore, the ability of a VANg-positive CLSE isolate to form a biofilm has been suggested as a biomarker of poor prognosis.
