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Determining the structure and phenotypic context of molecules detected in untargeted metabolomics experiments remains challenging. Here we present reverse metabolomics as a discovery strategy, whereby tandem mass spectrometry spectra acquired from newly synthesized compounds are searched for in public metabolomics datasets to uncover phenotypic associations. To demonstrate the concept, we broadly synthesized and explored multiple classes of metabolites in humans, including N-acyl amides, fatty acid esters of hydroxy fatty acids, bile acid esters and conjugated bile acids. Using repository-scale analysis1,2, we discovered that some conjugated bile acids are associated with inflammatory bowel disease (IBD). Validation using four distinct human IBD cohorts showed that cholic acids conjugated to Glu, Ile/Leu, Phe, Thr, Trp or Tyr are increased in Crohn's disease. Several of these compounds and related structures affected pathways associated with IBD, such as interferon-γ production in CD4+ T cells3 and agonism of the pregnane X receptor4. Culture of bacteria belonging to the Bifidobacterium, Clostridium and Enterococcus genera produced these bile amidates. Because searching repositories with tandem mass spectrometry spectra has only recently become possible, this reverse metabolomics approach can now be used as a general strategy to discover other molecules from human and animal ecosystems.

The objective of this study was to evaluate the impact of dietary zinc supplementation in pre-weaned dairy calves on the phenotypic antimicrobial resistance (AMR) of fecal commensal bacteria. A repository of fecal specimens from a random sample of calves block-randomized into placebo (n = 39) and zinc sulfate (n = 28) groups collected over a zinc supplementation clinical trial at the onset of calf diarrhea, calf diarrheal cure, and the last day of 14 cumulative days of zinc or placebo treatment were analyzed. Antimicrobial susceptibility testing was conducted for Enterococcus spp. (n = 167) and E. coli (n = 44), with one representative isolate of each commensal bacteria tested per sample. Parametric survival interval regression models were constructed to evaluate the association between zinc treatment and phenotypic AMR, with exponentiated accelerated failure time (AFT) coefficients adapted for MIC instead of time representing the degree of change in AMR (MIC Ratio, MR). Findings from our study indicated that zinc supplementation did not significantly alter the MIC in Enterococcus spp. for 13 drugs: gentamicin, vancomycin, ciprofloxacin, erythromycin, penicillin, nitrofurantoin, linezolid, quinupristin/dalfopristin, tylosin tartrate, streptomycin, daptomycin, chloramphenicol, and tigecycline (MR = 0.96-2.94, p > 0.05). In E. coli, zinc supplementation was not associated with resistance to azithromycin (MR = 0.80, p > 0.05) and ceftriaxone (MR = 0.95, p > 0.05). However, a significant reduction in E. coli MIC values was observed for ciprofloxacin (MR = 0.17, 95% CI 0.03-0.97) and nalidixic acid (MR = 0.28, 95% CI 0.15-0.53) for zinc-treated compared to placebo-treated calves. Alongside predictions of MIC values generated from these 17 AFT models, findings from this study corroborate the influence of age and antimicrobial exposure on phenotypic AMR.

Introduction: Enterococcus are considered an important genus in terms of Hospital-Acquired Infections (HAIs), which means that their characterization regarding resistance and virulence profiles in the hospital environment is of extreme importance. This article addresses this issue through the characterization of enterococci collected from a Veterinary Biological Isolation and Containment Unit (BICU). Methods: A total of 73 isolates, collected from different surfaces of a Veterinary BICU, were identified as Enterococcus through PCR at species level, after which 34 isolates were selected as representatives using (GTG)5 fingerprinting. These isolates were further characterized phenotypically in terms of antimicrobial resistance through disk diffusion and of virulence factors' expression. Results: The majority of the enterococci isolated presented resistance to erythromycin (79.4%), ampicillin (73.5%), amoxicillin-clavulanic acid (70.6%), tetracycline (67.6%), ciprofloxacin (58.8%) and levofloxacin (50.0%), and were able to produce hemolysin (88.2%) and biofilm (82.3%). Furthermore, in terms of pathogenicity, three isolates (8.8%) were classified as high threats and two (5.9%) as moderate threats. Discussion: The degree of resistance, production of virulence factors and the percentage of isolates classified as moderate or high threat means that a constant vigilance of such strains in veterinary units, but also in clinics and hospitals in general, is an important tool in terms of infection prevention and consequent reduction of HAIs. [ABSTRACT FROM AUTHOR]

During challenge of Caenorhabditis elegans with human bacterial pathogens such as Pseudomonas aeruginosa and Enterococcus faecalis , the elicited host response can be damaging if not properly controlled. The activation of Nrf (nuclear factor erythroid-related factor)/CNC (Cap-n-collar) transcriptional regulators modulates the response by upregulating genes that neutralize damaging molecules and promote repair processes. Activation of the C. elegans Nrf ortholog, SKN-1 , is tightly controlled by a myriad of regulatory mechanisms, but a central feature is an activating phosphorylation accomplished by the p38 mitogen-activated kinase (MAPK) cascade. In this work, loss of CDC-48, an AAA+ ATPase, was observed to severely compromise SKN-1 activation on pathogen and we sought to understand the mechanism. CDC-48 is part of the endoplasmic reticulum (ER)-associated degradation (ERAD) complex where it functions as a remodeling chaperone enabling the translocation of proteins from the ER to the cytoplasm for degradation by the proteosome. Interestingly, one of the proteins retrotranslocated by ERAD, a process necessary for its activation, is SKN-1A, the ER isoform of SKN-1. However, we discovered that SKN-1A is not activated by pathogen exposure in marked contrast to the cytoplasmic-associated isoform SKN-1C. Rather, loss of CDC-48 blocks the antioxidant response normally orchestrated by SKN-1C by strongly inducing the unfolded protein response (UPRER). The data are consistent with the model of these 2 pathways being mutually inhibitory and support the emerging paradigm in the field of coordinated cooperation between different stress responses. [ABSTRACT FROM AUTHOR]

Factors contributing to variations in the quality and microbiota of ensiled forages and in bulk tank microbiota in milk from cows fed different forages were investigated. Nutritional quality, fermentation parameters and hygiene quality of forage samples and corresponding bulk tank milk samples collected in 3 periods from 18 commercial farms located in northern Sweden were compared. Principal coordinates analysis revealed that the microbiota in forage and bulk milk, analyzed using 16S rRNA gene-based amplicon sequencing, were significantly different. The genera Lactobacillus , Weissella , and Leuconostoc dominated in forage samples, whereas Pseudomonas , Staphylococcus , and Streptococcus dominated in bulk milk samples. Forage quality and forage-associated microbiota were affected by ensiling method and by use of silage additive. Forages stored in bunker and tower silos (confounded with use of additive) were associated with higher levels of acetic and lactic acid and Lactobacillus. Forage ensiled as bales (confounded with no use of additive) was associated with higher DM content, water-soluble carbohydrate content, pH, yeast count, and the genera Weissella , Leuconostoc , and Enterococcus. For bulk tank milk samples, milking system was identified as the major factor affecting the microbiota and type of forage preservation had little effect. Analysis of common amplicon sequence variants (ASV) suggested that forage was not the major source of Lactobacillus found in bulk tank milk. The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. [ABSTRACT FROM AUTHOR]

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This study investigated the effects of Enterococcus hirae (Eh) derived from Ningxiang pigs on growth performance, diarrhea incidence, and immune responses in ETEC-challenged piglets. The results showed that compared to the CON group, ETEC infection significantly reduced the average daily gain (ADG) and average daily feed intake (ADFI), increased rectal temperature, and resulted in a diarrhea rate of up to 24%. Additionally, ETEC infection significantly increased the spleen index and the expression of inflammatory cytokines in the spleen, serum and intestine, with decreasing serum sIgA and colonic SCFAs of piglets. Compared to the ETEC group, orally Eh significantly increased ADFI in ETEC-infected piglets, reduced the diarrhea rate to 11.53%, reduced the spleen index and the expression of inflammatory cytokines in the spleen, serum and intestine, with decreasing serum sIgA and colonic SCFAs of ETEC-infected piglets. Furthermore, correlation analysis revealed that the levels of SCFAs (particularly acetate) were significantly negatively correlated with the expression levels of inflammatory cytokines in colonic and splenic tissues, suggesting that acetate may be a key metabolite in the anti-inflammatory effects of Eh. These results indicate that Eh can enhance the protection of piglets against ETEC K88 via intestine-acetate-spleen axis, thereby alleviating diarrhea and improving growth performance in piglets. [ABSTRACT FROM AUTHOR]

Medical professionals continue to face a severe issue with the evolution of resistance to conventional antibiotics. The search for new novel compounds from plants has been proven to be the alternative solution. Morinda citrifolia is used traditionally for the treatment of infectious diseases. The present study investigates the antibacterial properties of M. citrifolia root, leaf, and fruit (fresh, dried, and fermented) extracts on three-gram-positive and five-gram-negative bacteria. The plant parts were processed and extracted in distilled water and ethanol (60%, 80%, and absolute (100%)). The antibacterial activities of the extracts were assessed in vitro using the agar well diffusion method, with Ciprofloxacin serving as the positive control. All the tests were conducted three times to obtain the average value of inhibition zones. Overall, root extracts showed the most significant antibacterial activity, followed by dried fruit, fermented fruit extract, fresh fruit, and the least leaf extract. Using one-way ANOVA and Tukey's post-hoc tests, the statistical analysis revealed significant differences in antibacterial activity among the extracts and solvent concentrations. The 100% ethanol extracts had significantly higher zones of inhibition compared to the other solvents. The most inhibitory activity was against Campylobacter spp. (21.33±1.80) for the 80% ethanol root extract. All the extracts of M. citrifolia were found to exhibit moderate antibacterial activity against all the bacteria pathogens. However, Enterococcus faecium, Campylobacter spp., and Bacillus cereus were most sensitive to all the plant extracts while Shigella spp. and Klebsiella spp. showed resistance to most extracts. This observed difference is significant for each strain extract depending on the bacteria strain and the type of solvent extract (p < 0.001). The findings indicate a promising antimicrobial potential of M. citrifolia extracts. [ABSTRACT FROM AUTHOR]

Background: Infections caused by biofilm-forming bacteria have significantly linked to dental plaque and caries. The aim of this study is to assess efficacy of some natural compounds in inhibition and eradication of biofilm formed by bacterial isolates from dental infections. Results: Bacterial isolates were recovered from dental plaque/caries and identified using standard microbiological tests and 16S rDNA sequencing. The isolated bacterial strains include Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Klebsiella pneumoniae, and Escherichia coli. The antibiotic susceptibility was determined by disk diffusion method and revealed that the majority of isolates showed high antibiotic resistance, and 61% of isolates were found to be multidrug resistant. The biofilm formation capacity of isolates was investigated using microtiter plate assay. Among the 77 bacterial isolates, seventeen showed moderate biofilm formation capacity, twenty-two showed near-moderate, thirty-four had weak biofilm-forming capacity, and four were non-biofilm producers. The antibiofilm activity of tested compounds (rose and jasmine oils, propolis, vanillin, and vinegar) was evaluated against isolates with highest biofilm-forming capacity. The in vitro antibiofilm ability of tested substances were investigated alone or in combination with each other to evaluate their ability to prevent biofilm formation or destroy preformed single-/multispecies biofilms. Finally, antibiofilm ability of tested combination was evaluated ex vivo on natural teeth. Our results showed that vanillin in combination with rose or jasmine oils showed promising biofilm inhibition and biofilm eradication activities in both the in vitro and ex vivo models. Conclusions: Dental plaque and caries can be successfully prevented using combination of vanillin with rose or jasmine oils, and these compounds can be incorporated in new anticaries dental formulations. [ABSTRACT FROM AUTHOR]

Background: Antibiotic resistance in uropathogens has rapidly escalated over time, complicating treatment and increasing morbidity and mortality. Few studies have explored how the social determinants of health may be associated with patients' risks for acquiring antibiotic-resistant (AR) uropathogens. Methods: We identified urine cultures collected from outpatients presenting to Tufts Medical Center Primary Care Practices between 2015 and 2020. Specimens were included if patients' age, sex, and residential address were recorded in the electronic medical record (EMR) and if their urine culture yielded Enterococcus spp. or one or more gram-negative bacterial organism(s) or for which antibiotic susceptibility profiling and species identification was conducted. We abstracted patients' sociodemographic characteristics from the EMR and used US Census Bureau data to identify characteristics about patients' census tracts of residence. We evaluated associations between individual- and neighborhood-level characteristics and patients' risk of having a urine culture resistant to (1) three or more antibiotic classes (i.e., multidrug resistant [MDR]), (2) first-line treatments, (3) fluoroquinolones, (4) aminoglycosides, or (5) ceftriaxone using logistic regression models and a Bonferroni correction to account for multiple hypothesis testing. Results: We included urine cultures from 1,306 unique outpatients, most of whom were female (89%). Patients largely self-identified as Non-Hispanic White (36%), Asian (15%), or Non-Hispanic Black (11%). Over 60% lived in an environmental justice-designated census tract. Most included isolates were Escherichia coli (76%) or Klebsiella pneumoniae (7%). Using public insurance increased patients' odds of having a uropathogen resistant to first-line antibiotics, but living in a limited-income neighborhood reduced patients' odds of having a MDR uropathogen by 47%. We noted a strong but non-significant positive trend between speaking a language other than English and having an aminoglycoside-resistant uropathogen (p-value = 0.02). Most notably, after controlling for other factors, we observed no statistically significant associations between race or ethnicity and AR uropathogens. Conclusion: The social determinants of health may play important and intersecting roles in determining a patient's risk of having a resistant uropathogens that is more challenging or expensive to treat. It is crucial to acknowledge how race is likely to be a proxy for other factors affecting health, and to consider that some groups may be disproportionately impacted by antibiotic resistance. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the presence of ESKAPE organisms on the hands of students working in the intensive care unit (ICU) at a veterinary academic hospital. Methods: A cross-sectional study was conducted among students working in an ICU at a veterinary academic hospital in South Africa. Students were sampled before the start of the ICU shift using a modified glove-juice method. Standard microbiological techniques and a series of polymerase chain reaction (PCR) assays were used to identify and characterize the bacteria. All the isolates were tested for resistance against a specific panel of antibiotics using the disk diffusion method. Proportions of bacterial species and their antimicrobial-susceptibility profiles were calculated. Results: At screening, all the veterinary students (n = 62) carried at least one of the ESKAPE organisms on their hands. Escherichia coli was the most isolated organism (76%, 47/62), followed by P. aeruginosa (48%, 30/62), A. baumannii (47%, 29/62), E. faecium (35%, 22/62), K. pneumoniae (27%, 17/62), and S. aureus (24%, 15/62). A reduced proportion of isolates were recovered from the samples, E. coli (26%, 12/47), E. faecium (23%, 5/22), P. aeruginosa (43%, 13/30), A. baumannii (24%,7/29), K. pneumoniae (41%, 7/17), and S. aureus (20%, 3/15). Most of the organisms showed a high proportion of resistance to at least one antibiotic. Multidrug resistance was reported among just over half (56%, 5/9) of E. coli, 40% (2/5) of E. faecium, 100% (13/13) of P. aeruginosa, and 33% (1/3) of S. aureus isolates. Conclusion: Students working in the ICU carry several organisms belonging to the ESKAPE group of organisms before contact with patients. Moreover, MDR resistance was common among this group of organisms. The findings of the present study underscore the importance of infection prevention and control (IPC) strategies to help reduce the likelihood of the spread of these organisms to personnel, owners, family members, and patients. [ABSTRACT FROM AUTHOR]

Background: Alteration in the etiology of pediatric bloodstream infections (BSIs) and antimicrobial resistance (AMR) is not well known during the Coronavirus disease 2019 (COVID-19) pandemic. This study aimed to investigate the impact of the COVID-19 pandemic on pediatric BSIs and alteration in antimicrobial resistance phenotypes in Gram-positive bacteria. Methods: The frequency of BSIs among children under 18 years old was retrospectively recorded in a tertiary children's hospital in Tehran, Iran from February 2020 to December 2022. The status of COVID-19 infection using reverse transcription polymerase chain reaction, bacteremia/fungemia according to BACTEC 9120 Culture System results, characterization of bacteria using biochemical tests, and antimicrobial susceptibility patterns for Gram-positive bacterial isolates using disk diffusion method were determined. Statistical analysis was done to measure the correlation of COVID-19 infection with BSIs and AMR. Results: Out of 13,345 COVID-19 tests and 4,194 BACTEC blood culture requests, bacteremia/fungemia were confirmed in 10.37% (435/4,194) of the patients who requested both tests simultaneously. The COVID-19 infection was confirmed in 25.3% (110/435) of the patients with bacteremia/fungemia. The infection with characterized Gram-positive bacteria (GPB) and fungi was detected in 32.3% (140/433) and 8.31% (36/433) of the cases, respectively. Coagulase-negative Staphylococcus (CNS, 72, 16.62%), S. aureus (36, 8.3%), and Enterococcus spp. (22, 5%) were among the common isolates. Candida spp. and non-Candida yeasts were detected in 6.7% and 13.4% of the cases, respectively. A positive correlation was shown between the CNS bacteremia and COVID-19 infection (p-value = 0.019). Antibiotic susceptibility testing results showed the highest frequency of resistance to azithromycin among CNS, azithromycin and tetracycline among S. aureus and tetracycline among Enterococcus spp. Methicillin-resistance phenotype in the S. aureus (MRSA) and coagulase-negative Staphylococcus spp. (MR-CNS) was detected in 40% and 61.5% of the strains, respectively and the Enterococci were resistant to vancomycin in 33.3% of the isolates. Conclusion: A decline in the trend of BSIs by GPB and an increase in AMR was shown in children during the COVID-19 pandemic. Increasing antibiotic resistance is a concern; however, chloramphenicol, linezolid, and vancomycin remain active against common causes of GPB-BSIs. [ABSTRACT FROM AUTHOR]

This study aimed to design sustained released biodegradable calcium carbonate nanoparticles loaded with chlorhexidine (CHX-loaded NPs) and to investigate the early osteogenic differentiation and antimicrobial effects on the important bacteria involved in infections of dental implants. The microemulsion method was used to prepare the calcium carbonate nanoparticles loaded with chlorhexidine. The prepared nanoparticles were characterized using conventional methods. The release pattern determination and the biodegradation test were performed for the prepared nanoparticles. For the early osteogenic differentiation test of the prepared nanoparticles, alkaline phosphatase (ALP) activity was detected in human dental pulp stem cells (HDPSCs). The antimicrobial effects of the nanoparticles were evaluated against Escherichia coli, Streptococcus mutans, Enterococcus faecalis, Staphylococcus aureus, and Pseudomonas aeruginosa. The sizes of free calcium carbonate nanoparticles and CHX-loaded NPs were 105 ± 1.63 and 118 ± 1.47 nm and their zeta potentials were − 27 and − 36, respectively. A 50% degradation of nanoparticles was achieved after 100 days. These nanoparticles showed a two-stage sustained release pattern in vitro. Microscopic images revealed that the morphology of free calcium carbonate nanoparticles primarily took on a spherical calcite form, while CHX-loaded NPs predominantly exhibited a cauliflower-like vaterite polymorph. The nanoparticles increased the activity of ALP in cells in two weeks significantly (p < 0.05). Antimicrobial and antibiofilm results showed an efficient effect of the prepared nanoparticle against the studied bacteria. Calcium carbonate nanoparticles are an efficient multifunctional vector for chlorhexidine and can be used as a bioactive antibacterial agent against various oral microorganisms to prevent implant infections. [ABSTRACT FROM AUTHOR]

Background: This study investigates the safety evaluation of enterocin-producing 11 E. mundtii and two E. faecium strains previously isolated from small livestock colostrums. Enterococcus species do not possess Generally Recognized as Safe (GRAS) status. Hence, it is critical to scrutinize enterococci's antibiotic resistance, virulence characteristics, and biogenic amine production capabilities in order to assess their safety before using them as starter or adjunct cultures. Results: Enterococcus strains showed susceptibility to medically significant antibiotics. Multiple-drug resistance (MDR) was found in only E. faecium HC121.4, and its multiple antibiotic resistance (MAR) index was detected to be 0.22. The tetL and aph(3')-IIIa were the most commonly found antibiotic resistance genes in the strains. However, E. mundtii strains HC56.3, HC73.1, HC147.1, and E. faecium strain HC121.4 were detected to lack any of the antibiotic resistance genes examined in this study. Only E. mundtii HC166.3 showed hemolytic activity, while none of the strains engage in gelatinase activity. The strains were identified to have virulence factor genes with a low rate. None of the virulence factor genes could be detected in E. mundtii HC26.1, HC56.3, HC73.1, HC165.3, HC166.8, and E. faecium HC121.4. The E. mundtii HC73.2 strain displayed the highest presence of virulence factor genes, namely gelE, efaAfs, cpd, and ccf. Similarly, the E. mundtii HC112.1 strain showed a significant presence of genes efaAfm, ccf, and acm. There was no decarboxylation of histidine, ornithine, or lysine seen in any of the strains. Nevertheless, E. faecium HC121.4 and HC161.1 strains could decarboxylate tyrosine, but E. mundtii HC26.1, HC56.3, HC73.1, HC73.2, HC112.1, HC147.1, HC155.2, HC165.3, HC166.3, HC166.5, and HC166.8 strains only showed a limited capacity for tyrosine decarboxylation. None of the strains possessed the hdc, odc, or ldc genes, but all of them had the tdc gene. Conclusion: The E. mundtii HC56.3 and HC73.1 strains were deemed appropriate for utilization in food production. Using the remaining 11 strains as live cultures in food production activities could pose a possible risk to consumer health. [ABSTRACT FROM AUTHOR]

Background: Probiotics, which are live microorganisms that, when given in sufficient quantities, promote the host's health, have drawn a lot of interest for their ability to enhance gut health. Enterococcus faecalis, a member of the human gut microbiota, has shown promise as a probiotic candidate due to its functional attributes. However, safety concerns associated with certain strains warrant comprehensive evaluation before therapeutic application. Materials and Methods: In this study, E. faecalis EF-2001, originally isolated from fecal samples of a healthy human infant, was subjected to a multi-faceted assessment for its safety and probiotic potential. In silico analysis, CAZyme, biosynthetic, and stress-responsive proteins were identified. Results: The genome lacked biogenic amine genes but contained some essential amino acid and vitamin synthetic genes, and carbohydrate-related enzymes essential for probiotic properties. The negligible difference of 0.03% between the 1st and 25th generations indicates that the genetic information of the E. faecalis EF-2001 genome remained stable. The live E. faecalis EF-2001 (E. faecalis EF-2001L) demonstrated low or no virulence potential, minimal D-Lactate production, and susceptibility to most antibiotics except some aminoglycosides. No bile salt deconjugation or biogenic amine production was observed in an in vitro assay. Hemolytic activity assessment showed a β-hemolytic pattern, indicating no red blood cell lysis. Furthermore, the EF-2001L did not produce gelatinase and tolerated simulated gastric and intestinal fluids in an in vitro study. Similarly, heat-killed E. faecalis EF-2001 (E. faecalis EF-2001HK) exhibits tolerance in both acid and base conditions in vitro. Further, no cytotoxicity of postbiotic EF-2001HK was observed in human colorectal adenocarcinoma HT-29 cells. Conclusions: These potential properties suggest that probiotic and postbiotic E. faecalis EF-2001 could be considered safe and retain metabolic activity suitable for human consumption. [ABSTRACT FROM AUTHOR]

Today, there is a continuous worldwide battle against antimicrobial resistance (AMR) and that includes vancomycin-resistant enterococci (VRE). Methods that can adequately and quickly detect transmission chains in outbreaks are needed to trace and manage this problem fast and cost-effectively. In this study, DNA-microarray-based technology was developed for this purpose. It commenced with the bioinformatic design of specific oligonucleotide sequences to obtain amplification primers and hybridization probes. Microarrays were manufactured using these synthesized oligonucleotides. A highly parallel and stringent labeling and hybridization protocol was developed and employed using isolated genomic DNA from previously sequenced (referenced) clinical VRE strains for optimal sensitivity and specificity. Microarray results showed the detection of virulence, resistance, and species-specific genes in the VRE strains. Theoretical predictions of the microarray results were also derived from the sequences of the same VRE strain and were compared to array results while optimizing protocols until the microarray result and theoretical predictions were a match. The study concludes that DNA microarray technology can be used to quickly, accurately, and economically detect specifically and massively parallel target genes in enterococci. [ABSTRACT FROM AUTHOR]

The dominant lactic acid bacteria (LAB) population in traditional Muş Tulum cheese, which is produced from unpasteurized sheep’s milk, was identified during the ripening period (on the 1st, 45th, and 90th day) using biochemical, phenotypic, and genotypic techniques. Additionally, the isolated LAB strains were assessed for their technological characteristics. Enterococcus spp. accounted for 76.92 % of the sequenced isolates, while Lactiplantibacillus spp., Lactococcus spp., and Pediococcus spp. represented 15.38 %, 6.15 %, and 1.54 % respectively. All Lactococcus strains as well as E. faecium FFH2 and Lb. plantarum FFH59 strains showed high acidification capacity. E. faecalis (FFH46 and FFH14), L. lactis subsp. lactis FFH51 and E. faecium FFH16 strains showed high proteolytic activity (2.0593-2.2452 FFA mmol/L). Two Enterococcus strains (E. faecium FFH12 and E. faecium FFH77) with potential bacteriocin production and antimicrobial activity were identified. The results indicated that Enterococcus spp. was the dominant flora throughout the ripening period of Muş Tulum cheese, followed by Lactiplantibacillus spp [ABSTRACT FROM AUTHOR]

Enterococcus faecalis is considered a probiotic, commensal lactic acid bacterium in human breast milk (HBM), but there are circulating antibiotic resistant and virulence determinants that could pose a risk in some strains. The study aimed to conduct genomic analysis of E. faecalis isolates recovered from HBM and animal milk and to evaluate their probiotic and pathogenic features through comparative genomics with isolates from clinical specimens (e.g., urine, wound, and blood). Genomic analysis of 61 isolates was performed, including E. faecalis isolates recovered from HBM in Saudi Arabia. Genome sequencing was conducted using the MiSeq system. The fewest antibiotic resistance genes (lsaA, tetM, ermB) were identified in isolates from HBM and animal milk compared to clinical isolates. Several known and unknown mutations in the gyrA and parC genes were observed in clinical isolates. However, 11 virulence genes were commonly found in more than 95% of isolates, and 13 virulence genes were consistently present in the HBM isolates. Phylogenetically, the HBM isolates from China clustered with the probiotic reference strain Symbioflor 1, but all isolates from HBM and animal milk clustered separately from the clinical reference strain V583. Subsystem functions 188 of 263 were common in all analyzed genome assemblies. Regardless of the source of isolation, genes associated with carbohydrate metabolism, fatty acid, and vitamin biosynthesis were commonly found in E. faecalis isolates. In conclusion, comparative genomic analysis can help distinguish the probiotic or pathogenic potential of E. faecalis based on genomic features. [ABSTRACT FROM AUTHOR]

Background/Objectives: Wastewater treatment plants (WWTPs) are hotspots for the spread of antimicrobial resistance into the environment. This study aimed to estimate the proportion of clinically relevant antimicrobial-resistant bacteria in two Spanish urban WWTPs, located in the region of La Rioja (Spain); Methods: Ninety-four samples (48 water/46 sludge) were collected and streaked on ten different selective media, in order to recover the culturable bacterial diversity with relevant resistance phenotypes: Extended-Spectrum β-Lactamase-producing Escherichia coli/Klebsiella pneumoniae (ESBL-Ec/Kp), Carbapenem-resistant Enterobacteriaceae (CR-E), Methicillin-resistant Staphylococcus aureus (MRSA), and Vancomycin-resistant Enterococcus faecium/faecalis (VR-E. faecium/faecalis). Isolates were identified by MALDI-TOF and were tested for antimicrobial susceptibility using the disk diffusion method. The confirmation of ESBL production was performed by the double-disk test; Results: A total of 914 isolates were recovered (31 genera and 90 species). Isolates with clinically relevant resistance phenotypes such as ESBL-Ec/Kp and CR-E were recovered in the effluent (0.4 × 100–4.8 × 101 CFU/mL) and organic amendment samples (1.0–101–6.0 × 102 CFU/mL), which are discharged to surface waters/agricultural fields. We reported the presence of VR-E. faecium in non-treated sludge and in the digested sludge samples (1.3 × 101–1 × 103 CFU/mL). MRSA was also recovered, but only in low abundance in the effluent (0.2 × 101 CFU/mL); Conclusions: This study highlights the need for improved wastewater technologies and stricter regulations on the use of amendment sludge in agriculture. In addition, regular monitoring and surveillance of WWTPs are critical for early detection and the mitigation of risks associated with the spread of antimicrobial resistance. [ABSTRACT FROM AUTHOR]

Background/Objectives: Urinary tract infection (UTI) is a prevalent microbial infection in medical practise, leading to significant patient morbidity and increased treatment costs, particularly in developing countries. This retrospective study, conducted at a tertiary care hospital in Dhaka, Bangladesh, aims to examine the antimicrobial resistance (AMR) patterns of uropathogens and evaluate whether these patterns are influenced by demographic factors such as gender, age, or patient status. Methods: Standard microbiological techniques were used to identify uropathogens, and AMR patterns were determined using the Kirby–Bauer disc diffusion method. Results: Out of 6549 urine samples, 1001 cultures were positive. The infection was more prevalent in females compared to males. The incidence of UTIs in children aged 0–10 years accounted for 12.59% of the total cases, with this age group also exhibiting the highest rate of polymicrobial infections. Among the bacterial uropathogens, 71.19% of isolates were multidrug resistant (MDR) and 84.27% were resistant to at least one antibiotic. Escherichia coli (n = 544, 73.90% MDR) and Klebsiella species (n = 143, 48.95% MDR) were the most common Gram-negative uropathogens, while Enterococcus species (n = 78, 94.87% MDR) was the predominant Gram-positive isolate in this study. Our results indicate that most uropathogens showed resistance against ceftazidime, followed by cefuroxime, trimethoprim-sulfamethoxazole, amoxicillin-clavulanate, and netilmicin. Moderate levels of resistance were observed against ciprofloxacin, levofloxacin, aztreonam, and cefpodoxime. Conclusions: Amikacin was observed to be effective against Gram-negative uropathogens, whereas cefixime was more active against Gram-positive microorganisms, such as Enterococcus species. Moreover, a principal coordinate analysis (PCoA) depicted no significant influence of gender, patient status, or age on AMR patterns. For the continued usefulness of most antibiotics, periodic analysis of the AMR patterns of uropathogens can help assess the rise of MDR bacteria, and therefore guide the selection of appropriate antibiotic treatment strategies. [ABSTRACT FROM AUTHOR]

Yogurt is generally defined as a cultured milk product made using some species of lactic acid bacteria. Moreover, some additive bacteria are frequently involved in yogurts to provide health benefits. The objective of this study was testing the stability and survival of a beneficial strain with postbiotic activity, Enterococcus durans ED 26E/7, in cow, goat, and ewe–goat milk yogurts. The validated methods were used in the study. Postbiotic, concentrated substance (CBs) from the strain ED 26E/7 inhibited growth of indicator bacteria by 60.5%. The strains E. hirae (96%) were susceptible to CBs (inhibitory activity from 200 to 25,600 AU/mL). The growth of staphylococci was inhibited by 79% with activity of 100 up to 25,600 AU/mL. Also, 40 out of 46 fecal E. coli were inhibited (activity 100 AU/mL). CBs was thermo-stable and remained active also after storage for 11 months at −20 °C and −80 °C. Exposing CBs to proteolytic enzymes did not lead to its complete deactivation indicating that it is probably not only a proteinaceous substance. The highest counts of the freeze-dried (encapsulated), safe ED 26E/7 strain and its stability were detected in ewe–goat milk yogurts. They reached up to 5.0 cfu/g. ED 26E/7 represents a further promising additive, although other testing will be performed. [ABSTRACT FROM AUTHOR]

The ability of lactic acid bacteria (LAB) to produce biogenic amines (BAs) from amino acids using amino acid decarboxylase enzymes is an important food safety criterion due to their use as starter or bio-protective cultures. In this study, various LAB isolates, including Lactococcus (three isolates), Lactobacillus (five isolates), Enterococcus (13 isolates), and Leuconostoc (seven isolates), were isolated from ready-to-eat fish products like sauced, marinated, smoked anchovies, and smoked mackerel. These isolates were then tested for their ability to produce BAs (histamine, putrescine, cadaverine, spermidine, tryptamine, 2-phenylethylamine, spermine, serotonin, tyramine, 3-methylamine, and dopamine) and ammonia in histidine decarboxylase broth. The post-biotic solutions (cell-free supernatant) of Lb. paracasei NZ.Lbp.111, Lb. brevis NZ.Lbb.085, and E. casseliflavus NZ.Ec.074 exhibited the highest ammonia levels. Histamine accumulation was generally low in post-biotic solutions from four LAB isolates, ranging from 2.00 to 7.78 ppm. However, the post-biotic solution of Leu. mesenteroides NZLeu 009 displayed a significantly higher histamine concentration (83.23 ppm). Lactobacillus post-biotic solutions had the highest concentrations of ammonia (1220.28 ppm), 2-phenylethylamine (82.96 ppm), serotonin (278.70 ppm), tyramine (267.48 ppm), and cadaverine (19.72 ppm). Also, the average BAs concentration for Lactobacillus post-biotic solutions was the highest at 31.98 ppm. The results revealed the analysis of BAs concentrations in different LAB isolates from fish products, providing interesting insights into their metabolic capabilities and potential implications for food safety and quality. [ABSTRACT FROM AUTHOR]

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This study investigated the biofilm-forming capabilities of Enterococcus isolates from Portuguese traditional cheeses with protected designation of origin (PDO) status, specifically Azeitão and Nisa. Given the absence of added starter cultures in the cheesemaking process, the characteristics of these cheeses are intrinsically linked to the autochthonous microbiota present in the raw materials and the production environment. Our findings demonstrate that all isolates possess biofilm production abilities, which are crucial for their colonization and persistence within cheese factories, thereby maintaining factory-specific microbial heritage. Through an integrated analysis utilizing principal component analysis (PCA), a direct correlation between biofilm formation and cell viability was established. Notably, these results underscore the adaptive capacity of enterococci to survive environmental fluctuations and their role in the unique characteristics of Portuguese traditional cheeses. Overall, this research enhances our understanding of the microbial dynamics in cheese production and highlights the importance of enterococci in preserving cheese quality and heritage. [ABSTRACT FROM AUTHOR]

The main objective of this study is to isolate and identify lactic acid bacteria (LAB) from various Egyptian dairy products, examine their antibacterial and hemolysis potential, and ensure their safety when used as starter cultures in different dairy industries. Egyptian dairy products are often made without the use of commercial starter cultures, using raw milk and artisanal methods. The most popular traditional dairy products are Laban Rayeb and Zabady, as well as the cheese varieties of Ras, Domiati, and Karish. The microbial communities used for fermentation and the diversity of lactic acid bacteria are the most important factors that can affect the quality of these products. In order to investigate the diversity of cocci lactic acid bacteria in Egyptian dairy products, 70 samples of raw or fermented milk and cheeses were collected from traditional cheese-making factories, local markets, and farmhouses located in the Delta area of Egypt. Following this, the LAB were isolated from the samples. One hundred fifty-seven isolates of Gram-positive, catalase-negative, and cocci bacterial species were identified via rep-PCR, and some isolates were confirmed using pheS and 16S rRNA gene sequencing, as follows: Streptococcus infantarius subsp. infantarius (three isolates), Enterococcus hirae (three isolates), Enterococcus faecium (ninety-six isolates), Enterococcus faecalis (forty isolates), Enterococcus durans (six isolates), Lactococcus garvieae (one isolate), Pediococcus acidilactici (seven isolates), and Lactococcus lactis subsp. Lactis (one isolate). These findings validate that five strains have strong antibacterial activity against Escherichia coli, Salmonella typhimurium, and Listeria monocytogenes, and one hundred thirty-four strains were safe for hemolysis. The five strains were selected as protective cultures, including Pediococcus acidilactici, Lactococcus lactis subsp. lactis, E. faecalis, and E. faecium. [ABSTRACT FROM AUTHOR]

Vancomycin-resistant enterococci (VRE) are considered one of the main nosocomial pathogens due to their increasing antibiotic resistance and ability to cause life-threatening infections in humans. This study included VRE isolates obtained from various specimens including urine, blood, faeces, wounds, sputum, and oral cavity wash. Of the 37 strains, 30 (81.1%) and 7 (18.9%) were identified by MALDI TOF as Enterococcus faecium and Enterococcus faecalis, respectively. The clinical vancomycin-resistant enterococci exhibited multi-drug resistance (MDR). Apart from vancomycin, the enterococci exhibited resistance to penicillins (89.1 to 100%), fluoroquinolones (100%), rifampicin (86.5%), tetracycline (27%), aminoglycosides (56.8 to 86.5%), quinupristin–dalfopristin (35.1%), and chloramphenicol (10.8%). Moreover, resistance to linezolid and tigecycline emerged among the tested vancomycin-resistant enterococci. The analysis of aminoglycoside modifying enzyme (AME) genes showed the presence of bifunctional aac(6′)-Ie-aph(2″)-Ia genes contributed to high-level aminoglycoside resistance (HLAR) in the E. faecalis and E. faecium isolates. The other AME gene, i.e., aph(3′)-IIIa, was also found in the VRE isolates. All strains carried the vanA gene. Enterococci from colonised gastrointestinal tracts (1/2.7%) and from infection (6/16.2%) showed cytotoxic activity against the human epithelial cell line HEp-2. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance is an increasing societal burden worldwide, with ESKAPEE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter species and Escherichia coli) pathogens overwhelming the healthcare sectors and more recently becoming predominantly a concern for their persistence in food and food industries, including agricultural settings and animal husbandry environments. The aim of this review is to explore the mechanisms by which the ESKAPEE group gained its multidrug resistance profiles, to analyse their occurrence in different foods and other related reservoirs, including water, and to address the current challenges due to their spread within the food production chain. Moreover, the repertoire of surveillance programmes available focused on monitoring their occurrence, common reservoirs and the spread of antimicrobial resistance are described in this review paper. Evidence from the literature suggests that restricting our scope in relation to multidrug resistance in ESKAPEE pathogens to healthcare and healthcare-associated facilities might actually impede unveiling the actual issues these pathogens can exhibit, for example, in food and food-related reservoirs. Furthermore, this review addresses the need for increasing public campaigns aimed at addressing this challenge, which must be considered in our fight against antimicrobial resistance shown by the ESKAPEE group in food and food-related sectors. [ABSTRACT FROM AUTHOR]

In the present study, the presence of the Enterobacterales, Staphylococcus spp., Mammaliicoccus spp., and Enterococcus spp. in cloacal samples of nestling ospreys (Pandion haliaetus), a fish-eating specialist, from Mono Lake, California, USA was examined by a multiphasic approach, including antimicrobial and biocide susceptibility testing, genotyping, and whole genome sequencing of selected isolates. The most commonly detected species was Escherichia coli, followed by Mammaliicoccus sciuri, Staphylococcus delphini, Enterococcus faecalis, Enterococcus faecium, Hafnia alvei, Klebsiella pneumoniae, Citrobacter braakii and single isolates of Edwardsiella tarda, Edwardsiella albertii, Klebsiella aerogenes, Plesiomonas shigelloides and Staphylococcus pseudintermedius. Multi-drug resistance (MDR) was observed in two E. coli isolates and in an Enterococcus faecium isolate. The MDR blaCTX-M-55-positive E. coli belonged to the pandemic clone ST58. The results of the present study suggest that nestling ospreys are exposed to MDR bacteria, possibly through the ingestion of contaminated fish. Ospreys may be good biosentinels for the presence of these microorganisms and antibiotic resistance in the local environment and the risk for other wildlife, livestock and humans. [ABSTRACT FROM AUTHOR]

Background: Bacterial antimicrobial resistance (AMR) is a global threat to both humans and livestock. Despite this, there is limited global consensus on data-informed, priority areas for intervention in both sectors. We compare current livestock AMR data collection efforts with other variables pertinent to human and livestock AMR to identify critical data gaps and mutual priorities. Methods: We globally synthesized livestock AMR data from open-source surveillance reports and point prevalence surveys stratified for six pathogens (Escherichia coli, Staphylococcus aureus, non-typhoidal Salmonella, Campylobacter spp., Enterococcus faecalis, Enterococcus faecium) and eleven antimicrobial classes important in human and veterinary use, published between 2000 and 2020. We also included all livestock species represented in the data: cattle, chickens, pigs, sheep, turkeys, ducks, horses, buffaloes, and goats. We compared this data with intended priorities calculated from: disability-adjusted life years (DALYs), livestock antimicrobial usage (AMU), livestock biomass, and a global correlation exercise between livestock and human proportion of resistant isolates. Results: Resistance to fluoroquinolones and macrolides in Staphylococcus aureus were identified as priorities in many countries but, less than 10% of these reported livestock AMR data. Resistance data for Escherichia coli specific to cattle, chickens, and pigs, which we prioritized, were also well collected. AMR data collection on non-typhoidal Salmonella and other livestock species were often not prioritized. Of 232 categories prioritized by at least one country, data were only collected for 48% (n = 112). Conclusions: The lack of livestock AMR data globally for broad resistance in Staphylococcus aureus could underplay their zoonotic threat. Countries can bolster livestock AMR data collection, reporting, and intervention setting for Staphylococcus aureus as done for Escherichia coli. This framework can provide guidance on areas to strengthen AMR surveillance and decision-making for humans and livestock, and if done routinely, can adapt to resistance trends and priorities. [ABSTRACT FROM AUTHOR]

Studies on the conditions and pollution routes of antibiotic-resistant bacteria (ARB) in rivers can help provide countermeasures against the spread of ARB. This study focused on the pristine uppermost stream of a river, where Escherichia coli (E. coli) and enterococci were detected, although the stream flows through a pristine forest catchment. Antibiotic resistance of E. coli and enterococci isolated from the river water, riverbed sediment, and feces of waterside animals, such as birds and Mustelidae, were investigated throughout the year in the pristine uppermost sites. Antibiotic resistance was present in 1.4% (7/494) of the E. coli strains and 3.0% (24/812) of the enterococcal strains, and was low throughout the year. Although antibiotic resistance of bacteria isolated from feces was not detected in this watershed, the prevalence of multidrug-resistant E. coli was 0.4% (1/246) and 0.6% (1/172) in river water and riverbed sediment samples, respectively were observed. The presence of extended-spectrum β-lactamase (ESBL)-producing E. coli was confirmed in river water samples, and genomic analysis revealed that the samples possessed the CTX-M-15 group. Multidrug-resistant strains and ESBL-producing strains were classified as phylogroups B1 and A, respectively, which are E. coli phenotypes isolated from wild animals. Pulsed-field gel electrophoresis revealed analysis targeting enterococci that strains isolated from river water and bird feces were in the same cluster with 100% similarity. Therefore, bird feces are a source of enterococci in the uppermost stream of the river. Because multidrug-resistant bacteria and ESBL-producing bacteria were present in the pristine uppermost stream of the pristine river, urgent elucidation of the spreading routes of ARB is important. [ABSTRACT FROM AUTHOR]

Introduction: The global increase of multidrug-resistant organisms (MDROs) is one of the most urgent public health threats affecting both humans and animals. The One Health concept emphasizes the interconnectedness of human, animal and environmental health and highlights the need for integrated approaches to combat antimicrobial resistance (AMR). Although the sharing of environments and antimicrobial agents between companion animals and humans poses a risk for MDRO transmission, companion animals have been studied to a lesser extent than livestock animals. This study therefore used core genome multilocus sequence typing (cgMLST) to investigate the genetic relationships and putative transmission of MDROs between humans and pets. Methods: This descriptive integrated typing study included 252 human isolates, 53 dog isolates and 10 cat isolates collected from 2019 to 2022 at the Charité University Hospital in Berlin, Germany. CgMLST was performed to characterize methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci and multidrug-resistant gram-negative bacteria. The genetic diversity of the MDROs of the different host populations was determined and compared based on sequence type and core genome complex type. Results: Within this study the majority of samples from pets and humans was genetically distinct. However, for some isolates, the number of allelic differences identified by cgMLST was low. Two cases of putative household transmission or shared source of VR E. faecium and MDR E. coli between humans and pets were documented. Conclusions: The interaction between humans and their pets appears to play a minor role in the spread of the MDROs studied. However, further research is needed. This study emphasizes the importance of comprehensive molecular surveillance and a multidisciplinary One Health approach to understand and contain the spread of MDROs in human and animal populations. Trial Registration: The study is registered with the German Clinical Trials Register (DRKS00030009). [ABSTRACT FROM AUTHOR]

Background and objectives: Mineral Trioxide Aggregate (MTA) is one of the main retrograde filling materials that is used today as a root end filling material and perforation repair material. This study was conducted with the aim of investigating the antibacterial and antifungal properties of four types of bio-ceramic materials, AGM MTA, Ortho MTA, Pro root MTA and Cem cement for oral and dental health. Methods: In this study, the antibacterial activity of four types of bio-ceramic materials against two bacterial strains of Enterococcus faecalis (ATTC 29212), Escherichia coli (ATTC 35318) and antifungal activity against Candida albicans (ATTC 10231) were investigated using the well diffusion method. Results: In the context of the relationship between the type of microorganism and the diameter of the growth inhibitory zone for each type of bio-ceramic material, there was no significant difference for Enterococcus faecalis, and a significant difference was observed for Escherichia coli and Candida albicans (p < 0.05). Conclusion: The results show that each of the bio-ceramic materials AGM, Pro root, Cem cement and Ortho have antibacterial and antifungal properties. AGM MTA bio-ceramic material on Candida albicans fungus and Ortho MTA bio-ceramic material had the most effect on Escherichia coli bacteria. Therefore, the mentioned bio-ceramic materials can play a significant role in oral and dental health by providing a suitable material for restoration. [ABSTRACT FROM AUTHOR]

Purpose: Globally, colorectal cancer (CRC) is among the most prevalent cancers. One distinctive feature of colorectal cancer is its close relationship to the gut microbiota, which is a crucial component of the tumor microenvironment. Over the last ten years, research has demonstrated that colorectal cancer is accompanied with dysbiosis of gut bacteria, fungi, viruses, and Archaea, and that these alterations may be causal. Objectives: This study aimed to evaluate the disruption of the microorganism composition in the intestine, especially bacteria and to determine their relationship with colorectal cancer. Methods: An evaluation system for determining colorectal cancer (CRC) risk and prognosis can be established more easily with the help of accurate gut microbiota profiling. Stool samples from 14 CRC patients and 13 controls were collected and the flora relative abundance was measured using targeted quantitative PCR (qPCR) assays to evaluate diagnostic potential of selected biomarkers: Streptococcus gallolyticus and Enterococcus faecalis. Culture and MALDI-TOF mass spectrometry were coupled to identify the gut microbiota in both colorectal cancer and control groups. Results: Compared with controls, the gut microbiota of CRC patients showed an increase in the abundance of Enterococcus, Fusobacterium and Streptococcus. At the species level, the CRC enriched bacterium including Escherichia coli, Enterococcus faecalis, Fusobacterium nucleatum, Streptococcus gallolyticus, Flavoni fractorplautii and Eggerthella lenta acted as promising biomarkers for early detection of CRC. Conclusion: This study highlights the potential of gut microbiota biomarkers as a promising non-invasive tool for the accurate detection and distinction of individuals with CRC. [ABSTRACT FROM AUTHOR]

Background: The interactions between dysbiosis of gut microbiota and the development of colorectal cancers are well known. We investigated the effects of three different commercial probiotics, purchased from pharmacies, on several biological properties of enterococci (vancomycin-resistant "VRE" and vancomycinsusceptible "VSE") in colon adenocarcinoma cell culture (HT-29). Methods: Cell-free supernatants (CFSs) were prepared after isolating probiotic strains (Bifidobacterium lactis, Saccharomyces boulardii, and Bacillus clausii). Bacterial growth was detected spectrophotometrically after three, six, and 24 hours of incubation. Adhesion and invasion assays were performed using the colony counting method. Biofilm formation was performed using microtiter plate assay. GraphPad Prism software, version 5, was used for analysis. Results: After 24 hours incubation in culture medium, all three probiotics increased (P<0.001) the growth of VRE and VSE. Bacterial growth was also increased in cell culture in the presence of probiotics (P<0.001). Adhesion of both enterococci was reduced (P<0.001) by all probiotics. The invasion and biofilm formation were varied according to strains and probiotics tested. Conclusion: The effects of probiotics may vary depending on the specific strains used. Furthermore, during probiotic usage, potential risk of enhanced pathogenicity under certain circumstances, especially in immune suppression should be considered. [ABSTRACT FROM AUTHOR]

New biodegradable packaging has been developed from renewable sources, mainly of vegetable origin. Arrowroot starch has been recently used to produce high-quality biodegradable films capable of behaving well when incorporating oils, extracts, metal, and metal nanocomposites. The study aimed to verify the impact of incorporating metals in the sulfate and chloride forms in a biopolymeric matrix from arrowroot starch in terms of biodegradability, physicochemical and microbiological parameters. Different arrowroot films were produced to incorporate solutions with a concentration of 1 Mol L-1 of sulfate and chloride metals. The action of biodegradability in soil, UV transmittance, and visible light were observed in UV-Vis spectrophotometry and antimicrobial action on Escherichia coli, Staphylococcus aureus, Salmonella serovar Typhimurium, and Salmonella serovar Enteritidis. Good results were obtained, such as biodegradability time between 81.70 to 100% (30 days), a low transmission rate of UV radiation and visible light between 250 to 890 nm, high capacity for bacterial inhibition between 22.08 to 10.05 mm for E. coli, among 25.59 to 11.10 mm for S. aureus, between 22.14 to 11.66 mm for S. serovar Typhimurium and between 21.11 to 8.26 mm for S. serovar Enteritidis. It is concluded that the biodegradable films of arrowroot starch incorporated with metals showed potential in all the evaluated tests, thus characterizing possible new products for different uses, such as low time available in the environment, preservation of the characteristics of special products, and antimicrobial capacity. [ABSTRACT FROM AUTHOR]

The horizontal transfer of antibiotic resistance genes among bacteria is a pressing global issue. The bacterial defense system clustered regularly interspaced short palindromic repeats (CRISPR)-Cas acts as a barrier to the spread of antibiotic resistance plasmids, and CRISPR-Cas-based antimicrobials can be effective to selectively deplete antibiotic-resistant bacteria. While significant surveillance efforts monitor the spread of antibiotic-resistant bacteria in the clinical context, a major, often overlooked aspect of the issue is resistance emergence in agriculture. Farm animals are commonly treated with antibiotics, and antibiotic resistance in agriculture is on the rise. Yet, CRISPR-Cas efficacy has not been investigated in this setting. Here, we evaluate the prevalence of CRISPR-Cas in agricultural Enterococcus faecalis strains and its antiplasmid efficacy in an agricultural niche: manure. Analyzing 1,986 E. faecalis genomes from human and animal hosts, we show that the prevalence of CRISPR-Cas subtypes is similar between clinical and agricultural E. faecalis strains. Using plasmid conjugation assays, we found that CRISPR-Cas is a significant barrier against resistance plasmid transfer in manure. Finally, we used a CRISPR-based antimicrobial approach to cure resistant E. faecalis of erythromycin resistance, but this was limited by delivery efficiency of the CRISPR antimicrobial in manure. However, immunization of bacteria against resistance gene acquisition in manure was highly effective. Together, our results show that E. faecalis CRISPR-Cas is prevalent and effective in an agricultural setting and has the potential to be utilized for depleting antibiotic-resistant populations. Our work has broad implications for tackling antibiotic resistance in the increasingly relevant agricultural setting, in line with a One Health approach. [ABSTRACT FROM AUTHOR]

The Lactobacillales (LB) stand apart among bacterial orders, using manganese (Mn) instead of iron to support their growth and swiftly ferment complex foods while acidifying their environment. The present work investigates whether a shift in the use of Mn could mark the origin of LB. Transmembrane carriers of the ubiquitous Slc11 family play key roles in LB physiology by catalyzing proton-dependent Mn import. In prior studies, the Slc11 clade found in LB (MntH Cb, MCb) showed both remarkable structural plasticity and highly efficient Mn uptake, and another Slc11 clade, MCg1, demonstrated divergent evolution coinciding with emergence of bacterial genera (e.g., Bordetella, Achromobacter). Herein, the Slc11 clade MCb is subdivided in sister groups: MCbie and MCbgut. MCbie derives directly from the Slc11 clade MCa, pointing an intermediate stage in the evolution of MCbgut. MCbie predominates in marine Bacillaceae, is more conserved than MCbgut, lacks the structural plasticity that typify MCbgut carriers, and responds differently to identical mutagenesis. Exchanging MCbie/MCbgut amino acid residues at sites that distinguish these clades showed conformation-dependent effects with both MCbie and MCbgut templates, and the 3D location of the targeted sites in the carrier structure together suggests that the mechanism to open the inner gate, and release Mn into the cytoplasm, differs between MCbie and MCbgut. Building on the established phylogeny for Enterococcus revealed that a pair of genes encoding MCbgut was present in the common ancestor of LB, as MCbgu1 and MCbgu2 templates exhibited distinct structural dynamics properties. These data are discussed when examining whether MCbgut+ LB could emerge in the upper gut of early vertebrates (ca. 540 mya), through genome contraction and evolution toward Mn-centrism, as they specialized as gastric aids favoring stomach establishment in jawed vertebrates through bi-directional communication with host nervous, endocrine and immune systems. [ABSTRACT FROM AUTHOR]

Bio-protection is one of the most popular natural protection methods to control food safety and shelf life. Lactic acid bacteria, especially Lactobacilli strains, are used in the food industry for this purpose due to their probiotic properties and, accordingly, bioprotective properties. We aimed to investigate the role of the bacteriocin-producing lactic acid bacteria Lactobacillus sakei and Pediococcus acidilactici in inducing microbiological, physicochemical, and chemical changes in the Turkish-style fermented sausage sucuk. The effects of protective cultures were compared with those of commercial starter cultures consisting of Pediococcus pentosaceus + Staphylococcus carnosus; a non-cultured group was used as a control. L. sakei inoculation and, to a lower extent, P. acidilactici inoculation resulted in the rapid domination of lactic acid bacteria (LAB) in the environment, whereas commercially used starter cultures and the non-cultured group showed lower counts of LAB. Moreover, L. sakei and P. acidilactici succeeded in inhibiting pathogens including S. aureus, E. coli, and Enterobacteriaceae. The number of enterococci decreased notably in the L. sakei-inoculated sucuk samples; however, an increase was determined in the samples inoculated with P. acidilactici. On the other side, the effect of commercial starter cultures was not sufficient for the inhibition of food-borne pathogens in the sucuk samples. Consequently, the inoculation of protective cultures, particularly of L. sakei, can provide a considerable contribution to improving microbial quality and food safety, retarding lipid oxidation, and increasing proteolytic activities in sucuk without important changes in its sensory properties. [ABSTRACT FROM AUTHOR]

The emergence of antibiotic-resistant pathogens in clinical settings has intensified the search for new probiotic strains with both health benefits and technological utility. This study aims to identify and characterize promising antimicrobial cultures derived from milk and dairy products, capable of inhibiting opportunistic pathogens. The samples of dairy products were collected from various markets across Kazakhstan. Microorganisms isolated from these samples underwent identification through 16S rRNA and ITS gene sequencing, using the BLAST algorithm. Their antimicrobial activity was assessed using the delayed antagonism method against pathogenic microorganisms including E. coli, S. aureus, Pseudomonas sp., Candida sp., and B. subtilis. Additionally, the isolates were evaluated for resistance to environmental stress factors such as temperature, pH, salt, ethanol, glucose, and peroxide. From 24 distinct samples, 33 isolates were purified, with 15 demonstrating high viability (108–109 CFU/mL) and stress resistance. Notably, Lacticaseibacillus casei AK and Enterococcus faecium KS exhibited resistance to all tested stress conditions. Antimicrobial screening revealed strong activity by strains LP, LB, and S-2 against multiple pathogens. Genotyping and carbohydrate fermentation tests identified these effective isolates as belonging to the genera Lactobacillus, Lactococcus, Enterococcus, Lactiplantibacillus, Streptococcus, and the yeast genus Pichia. This study underscores the industrial and health potential of the identified microorganisms. Prominent among the strains, Lactiplantibacillus pentosus LP, Lacticaseibacillus casei AK, Lactiplantibacillus argentoratensis LB, Lactiplantibacillus plantarum S-2, and Enterococcus faecium KS have been recognized as potent probiotics. These strains exhibit broad-spectrum antimicrobial activity coupled with robust stress tolerance, making them suitable candidates for probiotic applications. [ABSTRACT FROM AUTHOR]

Key Clinical Message: This report presents a rare case of invasive infection caused by Enterococcus cecorum. There are no specific guidelines regarding antibiotic therapy for this infection. Based on this case, it can be concluded that linezolid demonstrates in vivo activity against Enterococcus cecorum and can be successfully used in therapy. Enterococcus cecorum is an extremely rare pathogen in humans. Since 1984, when the microorganism was first described, only a dozen cases of invasive infections in humans have been reported in the literature. The diagnostic pathway may involve difficulties in correctly identifying this microorganism. Based on the case described, it can be thought that Enterococcus cecorum is a more challenging bacterium than the much more common Enterococcus faecium or Enterococcus faecalis. The described case underscores the importance of medical vigilance in clinical practice. It seems that due to increasingly advanced techniques in molecular biology, we will more frequently detect pathogens that were previously encountered only sporadically. Since not every center has access to modern and advanced microbiological diagnostic methods, publications that practically combine classical microbiological diagnostic methods with those less accessible but more modern are exceptionally valuable. In the case described, it is also worth noting that classical methods still play a significant and crucial role in conducting microbiological diagnostics. In the era of rapid diagnostic tool development, it is important to emphasize the necessity of combining different methods rather than replacing one with another. [ABSTRACT FROM AUTHOR]

We developed a synthesis strategy involving a diazo transfer reaction and subsequent click reaction to conjugate a murine cathelicidin-related antimicrobial peptide (CRAMP18–35) to chitosan and hydroxypropyl chitosan (HPC), confirmed the structure, and investigated the antimicrobial activity. Chitosan azide and HPC-azide were prepared with a low degree of azidation by reacting the parent chitosan and HPC with imidazole sulfonyl azide hydrochloride. CRAMP18–35 carrying an N-terminal pentynoyl group was successfully grafted onto chitosan and HPC via copper-catalyzed azide–alkyne cycloaddition (CuAAC) reaction. The chitosan–peptide conjugates were characterized by IR spectroscopy and proton NMR to confirm the conversion of the azide to 1,2,3-triazole and to determine the degree of substitution (DS). The DS of the chitosan and HPC CRAMP18–35 conjugates was 0.20 and 0.13, respectively. The antibacterial activity of chitosan–peptide conjugates was evaluated for activity against two species of Gram-positive bacteria, Staphylococcus aureus (S. aureus) and Enterococcus faecalis (E. faecalis), and two species of Gram-negative bacteria, Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa). The antimicrobial peptide conjugates were selectively active against the Gram-negative bacteria and lacking activity against Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

One of the most prevalent infectious diseases identified in both communities and hospitalized patients is urinary tract infection (UTI). Enterococcus is evolved into a clinically pertinent uropathogen due to its evolving resistance to multiple antimicrobial agents.This study, detects antimicrobial susceptibility patterns of Enterococcus species and molecular detection of Enterococcus faecalis from patients with urinary tract infections. In this cross-sectional observational study, 165 urine samples were obtained from clinically diagnosed patients with UTIs of different ages and gender. Enterococcus species were identified by standard microbiological procedure and PCR (by using species-specific primers for Enterococcus faecalis). A modified Kirby Bauer Disc diffusion method was used to identify the antimicrobial susceptibility pattern following Clinical and Laboratory Standards Institute (CLSI) guidelines. Out of 165 urine samples, 134 samples yielded positive cultures. Enterococcus species were isolated from 23 (17.1%) urine samples. Among all Enterococcus, 16 (69.6%) isolates were E. faecalis, detected by PCR assay. A higher (30.4%) proportion of Enterococcus-positive patients were from the age group 48–57 years and female patients (78.2%) had a higher prevalence. Enterococcal infection was found in 56.5% of non-catheterized patients and 43.5% of catheterized patients. Vancomycin and linezolid (78.3%) and meropenem (73.9%) sensitivity was prevalent among all Enterococcus species. They showed 100% resistance towards ceftriaxone, cefixime 95.7%, cefuroxime 91.3%, azithromycin 82.6%. This research indicated the occurrence of Enterococcus species and the advent of multidrug-resistant E. faecalis in patients with UTIs. Routine speciation and antimicrobial susceptibility testing of Enterococcus in various clinical samples is encouraged. [ABSTRACT FROM AUTHOR]

Background/Objectives: ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) pose a serious public health threat as they are resistant to multiple antimicrobial agents. Bloodstream infections (BSIs) caused by ESKAPE bacteria have high mortality rates due to the limited availability of effective antimicrobials. This study aimed to evaluate the prevalence and susceptibility of ESKAPE pathogens causing BSIs over three years in a large tertiary hospital in Salerno. Methods: Conducted at the Clinical Microbiology Laboratory of San Giovanni di Dio e "Ruggi D'Aragona" Hospital from January 2020 to December 2022, blood culture samples from different departments were incubated in the BD BACTEC™ system for 5 days. Species identification was performed using MALDI-TOF MS, and antimicrobial resistance patterns were determined by the VITEK2 system. Results: Out of 3197 species isolated from positive blood cultures, 38.7% were ESKAPE bacteria. Of these, 59.9% were found in blood culture samples taken from men, and the most affected age group was those aged >60 years. (70.6%). Staphylococcus aureus was the main BSI pathogen (26.3%), followed by Klebsiella pneumoniae (15.8%). Significant resistance rates were found, including 35% of Staphylococcus aureus being resistant to oxacillin and over 90% of Acinetobacter baumannii being resistant to carbapenems. Conclusions: These results highlight the urgent need for antimicrobial stewardship programs to prevent incurable infections. [ABSTRACT FROM AUTHOR]

Endolysin, a bacteriophage-derived lytic enzyme, has emerged as a promising alternative antimicrobial agent against rising multidrug-resistant bacterial infections. Two novel endolysins LysPEF1-1 and LysPEF1-2 derived from Enterococcus phage PEF1 were cloned and overexpressed in Escherichia coli to test their antimicrobial efficacy against multidrug-resistant E. faecalis strains and their biofilms. LysPEF1-1 comprises an enzymatically active domain and a cell-wall-binding domain originating from the NLPC-P60 and SH3 superfamilies, while LysPEF1-2 contains a putative peptidoglycan recognition domain that belongs to the PGRP superfamily. LysPEF1-1 was active against 89.86% (62/69) of Enterococcus spp. tested, displaying a wider antibacterial spectrum than phage PEF1. Moreover, two endolysins demonstrated lytic activity against additional gram-positive and gram-negative species pretreated with chloroform. LysPEF1-1 showed higher activity against multidrug-resistant E. faecalis strain E5 than LysPEF1-2. The combination of two endolysins effectively reduced planktonic cells of E5 in broth and was more efficient at inhibiting biofilm formation and removing biofilm cells of E. faecalis JCM 7783T than used individually. Especially at 4 °C, they reduced viable biofilm cells by 4.5 log after 2 h of treatment on glass slide surfaces. The results suggest that two novel endolysins could be alternative antimicrobial agents for controlling E. faecalis infections. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance poses a major threat to global health and food security and is primarily driven by antimicrobial use in human and veterinary medicine. Understanding its epidemiology at farm level is crucial for effective control measures. Despite the significant reduction in antibiotic use in conventional livestock production, the swine sector traditionally has a higher level of antibiotic use in veterinary medicine. Consequently, multidrug resistance (MDR) among microbial isolates of swine origin has been relatively frequent. The aim of this study was to assess the presence of multidrug-resistant (MDR) bacteria, enteric pathogens and resistance genes to the main antibiotics used in clinical practice, both within the environment and in animals across pig farms characterized by varying degrees of sanitary status. A total of 274 samples were collected. Of these, 34 samples were collected from the environment (wall swabs, slat swabs and slurry pit), and 240 samples were collected from animals (sows' and piglets' rectal faeces). All samples were analysed for MDR bacteria and enteric pathogens. The study revealed a high frequency of extended-spectrum beta-lactamases (ESBL)-producing Enterobacterales and Campylobacter spp., with ESBL-producing Enterobacterales predominating in high health status farms (environment and animals) and Campylobacter spp. in both high health status and low health status environments. Additionally, a high percentage of methicillin-resistant Staphylococcus aureus (MRSA) was found, mainly in environmental samples from high health status farms, and Clostridioides difficile was distributed ubiquitously among farms and samples. Furthermore, though less frequently, vancomycin-resistant Enterococcus faecium (VRE) was isolated only in high health status farms, and Gram-negative bacilli resistant to carbapenems were isolated only in environmental samples of high health status and low health status farms. This study underscores the importance of surveillance for MDR bacteria in farm animals and their environment, including their waste. Such ecosystems serve as crucial reservoirs of bacteria, requiring national-level surveillance to promote responsible antibiotic use and pandemic control. [ABSTRACT FROM AUTHOR]

Vancomycin variable Enterococcus (VVE) bacteria are phenotypically susceptible to vancomycin, but they harbor the vanA gene. We aimed to ascertain the prevalence of VVE among clinically isolated vancomycin-susceptible Enterococcus faecium (VSE) isolates, as well as elucidate the molecular characteristics of the vanA gene cluster within these isolates. Notably, we investigated the prevalence and structure of the vanA gene cluster of VVE. Between June 2021 and May 2022, we collected consecutive, non-duplicated vancomycin-susceptible Enterococcus faecium (VSE) samples. Real-time PCR was performed to detect the presence of vanA, vanB, and vanC. Overlapping PCR with sequencing and whole -genome sequencing were performed for structural analysis. Sequence types (STs) were determined by multilocus sequence typing. Exposure testing was performed to assess the ability of the isolates to acquire vancomycin resistance. Among 282 VSE isolates tested, 20 isolates (7.1%) were VVE. Among them, 17 isolates had partial deletions in the IS1216 or IS1542 sequences in vanS (N=10), vanR (N=5), or vanH (N=2). All VVE isolates belonged to the CC17 complex and comprised five STs, namely ST17 (40.0%), ST1421 (25.0%), ST80 (25.0%), ST787 (5.0%), and ST981 (5.0%). Most isolates were related to three hospital-associated clones (ST17, ST1421, and ST80). After vancomycin exposure, 18 of the 20 VVEs acquired vancomycin resistance. Considering the high reversion rate, detecting VVE by screening VSE for vanA is critical for appropriate treatment and infection control. [ABSTRACT FROM AUTHOR]

Abstract Background This study investigates the safety evaluation of enterocin-producing 11 E. mundtii and two E. faecium strains previously isolated from small livestock colostrums. Enterococcus species do not possess Generally Recognized as Safe (GRAS) status. Hence, it is critical to scrutinize enterococci’s antibiotic resistance, virulence characteristics, and biogenic amine production capabilities in order to assess their safety before using them as starter or adjunct cultures. Results Enterococcus strains showed susceptibility to medically significant antibiotics. Multiple-drug resistance (MDR) was found in only E. faecium HC121.4, and its multiple antibiotic resistance (MAR) index was detected to be 0.22. The tetL and aph(3')-IIIa were the most commonly found antibiotic resistance genes in the strains. However, E. mundtii strains HC56.3, HC73.1, HC147.1, and E. faecium strain HC121.4 were detected to lack any of the antibiotic resistance genes examined in this study. Only E. mundtii HC166.3 showed hemolytic activity, while none of the strains engage in gelatinase activity. The strains were identified to have virulence factor genes with a low rate. None of the virulence factor genes could be detected in E. mundtii HC26.1, HC56.3, HC73.1, HC165.3, HC166.8, and E. faecium HC121.4. The E. mundtii HC73.2 strain displayed the highest presence of virulence factor genes, namely gelE, efaA fs , cpd, and ccf. Similarly, the E. mundtii HC112.1 strain showed a significant presence of genes efaA fm , ccf, and acm. There was no decarboxylation of histidine, ornithine, or lysine seen in any of the strains. Nevertheless, E. faecium HC121.4 and HC161.1 strains could decarboxylate tyrosine, but E. mundtii HC26.1, HC56.3, HC73.1, HC73.2, HC112.1, HC147.1, HC155.2, HC165.3, HC166.3, HC166.5, and HC166.8 strains only showed a limited capacity for tyrosine decarboxylation. None of the strains possessed the hdc, odc, or ldc genes, but all of them had the tdc gene. Conclusion The E. mundtii HC56.3 and HC73.1 strains were deemed appropriate for utilization in food production. Using the remaining 11 strains as live cultures in food production activities could pose a possible risk to consumer health.

Abstract Background and objectives Mineral Trioxide Aggregate (MTA) is one of the main retrograde filling materials that is used today as a root end filling material and perforation repair material. This study was conducted with the aim of investigating the antibacterial and antifungal properties of four types of bio-ceramic materials, AGM MTA, Ortho MTA, Pro root MTA and Cem cement for oral and dental health. Methods In this study, the antibacterial activity of four types of bio-ceramic materials against two bacterial strains of Enterococcus faecalis (ATTC 29212), Escherichia coli (ATTC 35318) and antifungal activity against Candida albicans (ATTC 10231) were investigated using the well diffusion method. Results In the context of the relationship between the type of microorganism and the diameter of the growth inhibitory zone for each type of bio-ceramic material, there was no significant difference for Enterococcus faecalis, and a significant difference was observed for Escherichia coli and Candida albicans (p

Hirschsprung-associated enterocolitis (HAEC) stands as most common and serious complication of Hirschsprung's disease. Variations in the microbiota composition may account for the differences observed between HAEC and healthy individuals, offering crucial insights into the disease's pathogenesis. Here, we performed a study to changes in the gut microbiome using 16sRNA amplicon sequencing in a cohort of HAEC patients (n = 16) and healthy controls (n = 14). Our result revealed a significant disparity in beta diversity between the two groups. Following correction for false discovery rate, a rank–sum test at the genus level indicated a notable decrease in the relative abundance of Bifidobacterium, Lactobacillus, and Veillonella, whereas the Enterococcus genus exhibited a substantial increase in HAEC, a finding further supported by additional linear discriminant analysis effect size analysis. Functional analysis showed that putative transport and catabolism, digestive system, and metabolism of cofactors and vitamins were proved to be some abundant KOs (Kyoto Encyclopedia of Genes and Genomes [KEGG] orthologs) in healthy group, whereas infectious disease, membrane transport, and carbohydrate metabolism were the three KOs with the higher abundance in the HAEC group. Our data increased our insight into the HAEC, which may shed further light on HAEC pathogenesis. Our study firstly demonstrated the difference between fecal microbiota of HAEC patients and healthy individuals, which made a step forward in the understanding of the pathophysiology of HAEC.