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Scientific Reports Oct 2023The emergence of antimicrobial-resistant, livestock-associated Enterococcus faecalis represents a public health concern. Here, we report the isolation, molecular...
Antimicrobial resistance and whole genome sequencing of novel sequence types of Enterococcus faecalis, Enterococcus faecium, and Enterococcus durans isolated from livestock.
The emergence of antimicrobial-resistant, livestock-associated Enterococcus faecalis represents a public health concern. Here, we report the isolation, molecular detection of virulence and antimicrobial resistance determinants, in addition to the phylogenetic analyses of 20 Enterococcus species using whole genome sequencing analysis of 15 Enterococcus faecalis strains including six strains of three novel sequence types, three Enterococcus faecium and two Enterococcus durans. All strains were isolated from food chain animals in South Africa. Enterococcus strains were isolated on bile aesculin azide agar, followed by identification using MALDI-TOF MS analysis. Antibiotic susceptibility testing was performed using the Kirby-Bauer disk diffusion method. The genomic DNA of the isolates was extracted and sequencing was performed using the Illumina MiSeq platform. Sequence reads were trimmed and de novo assembled. The assembled contigs were analyzed for antimicrobial resistance genes and chromosomal mutations, extra-chromosomal plasmids, and multi-locus sequence type (MLST). Multidrug antimicrobial resistance genes conferring resistance to aminoglycosides (ant(6)-Ia, aph(3')-IIIa, sat4, and spw), lincosamides (lnu(B), lsa(A), and lsa(E)), macrolides (erm(B)), trimethoprim (dfrG) and tetracyclines (tet(L) and tet(M)) were identified. Plasmid replicons were detected in seven E. faecalis and three E. faecium isolates. The sequence type (ST) of each isolate was determined using the Enterococcus PubMLST database. Ten STs were identified in the collection, three of which (ST1240, ST1241, and ST1242) have not been previously reported and are described in the present study for the first time. To compare the sequenced strains to other previously sequenced E. faecalis strains, assembled sequences of E. faecalis from livestock were downloaded from the PubMLST database. Core genome-based phylogenetic analysis was performed using ParSNP. The detection of multiple drug-resistance in Enterococcus including E. faecalis and E. faecium highlights the significance of genomic surveillance to monitor the spread of antimicrobial resistance in food chain animals. In addition, the genome sequences of Enterococcus strains reported in the present study will serve as a reference point for future molecular epidemiological studies of livestock-associated and antibiotic-resistant E. faecalis in Africa. In addition, this study enables the in-depth analysis of E. faecalis genomic structure, as well as provides valuable information on the phenotypic and genotypic antimicrobial resistance, and the pathogenesis of livestock-associated E. faecalis and E. faecium.
Topics: Animals; Enterococcus faecalis; Enterococcus faecium; Anti-Bacterial Agents; Livestock; Phylogeny; Multilocus Sequence Typing; Drug Resistance, Bacterial; Enterococcus; Whole Genome Sequencing; South Africa; Microbial Sensitivity Tests; Gram-Positive Bacterial Infections
PubMed: 37903806
DOI: 10.1038/s41598-023-42838-z -
Current Microbiology Jun 2023Exposure to ultraviolet (UV) radiation is one of the major factors that causes skin aging, erythema, sunburns, and skin cancer. This study aimed to select probiotic...
Exposure to ultraviolet (UV) radiation is one of the major factors that causes skin aging, erythema, sunburns, and skin cancer. This study aimed to select probiotic bacterial isolates able to produce high yield of hyaluronic acid (HA) to be employed for skin photoprotection and other possible biological applications. The selected isolates K11 and St3 were able to produce the highest yields of HA 4.8 and 4.4 mg/ml, respectively. Both isolates were identified as Enterococcus durans strain K11 and Lactiplantibacillus plantarum strain St3 using 16S rRNA gene sequencing. The antioxidant activity of HA produced by E. durans strain K11 and L. plantarum strain St3 was (65.4 0.2%) and (66.6 0.1%), respectively. The viability of UVB-irradiated keratinocytes pre-treated with HA produced by E. durans strain K11 and L. plantarum strain St3 was 91.3 and 91.4%, respectively, compared with the control. While the viability of UVB-irradiated keratinocytes post-treated with HA produced by E. durans strain K11 and L. plantarum strain St3 was 86 and 88.5%, respectively. To the best of our knowledge, this is the first recordation of HA production by Enterococcus durans and Lactiplantibacillus plantarum which revealed a significant radioprotection of the human keratinocytes against UVB radiation.
Topics: Humans; Hyaluronic Acid; RNA, Ribosomal, 16S; Enterococcus; Skin
PubMed: 37369929
DOI: 10.1007/s00284-023-03377-y -
Heliyon Apr 2024, is a potential functional strain with the capacity to regulate intestinal health and ameliorate colonic inflammation. However, the strain requires further...
, is a potential functional strain with the capacity to regulate intestinal health and ameliorate colonic inflammation. However, the strain requires further investigation regarding its safety profile and potential mechanisms of colitis improvement. In this study, the safety of 98D (Ed) as a potential probiotic was studied using methods. Additionally, a dextran sulfate sodium (DSS)-induced murine colitis model was employed to investigate its impact on the intestinal microbiota and colitis. antimicrobial assays revealed Ed sensitivity to common antibiotics and its inhibitory effect on the growth of O157, CCUG 37328, and ATCC 25923. To elucidate the functional properties of Ed, 24 weight-matched 6-week-old female C57BL/6J mice were randomly divided into three groups (n = 8): NC group, Con group (DSS), and Ed group (DSS + Ed). Ed administration demonstrated a protective effect on colitis mice, as evidenced by improvements in body weight, colonic length, reduced disease activity index, histological scores, diminished splenomegaly, and decreased goblet cell loss. Furthermore, Ed downregulated the expression of the pro-inflammatory cytokine genes (, , and ) and upregulated the expression of the anti-inflammatory cytokine gene . The 16S rRNA gene sequencing revealed significant alterations in microbial α-diversity, with principal coordinate analysis indicating distinct differences in microbial composition among the three groups. At the phylum level, the relative abundance of Actinomycetota significantly increased in the Ed-treated group. At the genus level, Ed treatment markedly elevated the relative abundance of , , and in DSS-induced colitis mice. In conclusion, Ed exhibits potential as a safe and effective therapeutic agent for DSS-induced colitis by reshaping the colonic microbiota.
PubMed: 38560132
DOI: 10.1016/j.heliyon.2024.e28486 -
Microbes and Infection 2023The genus Enterococcus is commonly overpopulated in patients with depression compared to healthy control in the feces. Therefore, we isolated Enterococcus faecalis,...
The genus Enterococcus is commonly overpopulated in patients with depression compared to healthy control in the feces. Therefore, we isolated Enterococcus faecalis, Enterococcus durans, Enterococcus gallinarum, Enterococcus faecium, and Enterococcus mundtii from the feces of patients with comorbid inflammatory bowel disease with depression and examined their roles in depression in vivo and in vitro. Of these Enterococci, E. mundtii NK1516 most potently induced NF-κB-activated TNF-α and IL-6 expression in BV2 microglia cells. NK1516 also caused the most potent depression-like behaviors in the absence of sickness behaviors, neuroinflammation, downregulated brain-derived neurotrophic factor (BDNF), and serotonin (5-HT) levels in the hippocampus of mice. Furthermore, E. mundtii NK1516 reduced the mRNA expression of Htr1a in the hippocampus. Its capsular polysaccharide (CP), but not cytoplasmic components, also caused depression-like behaviors and reduced BDNF and serotonin levels in the hippocampus. Conversely, this was not observed with E. mundtii ATCC882, a well-known probiotic, or its CP. Orally gavaged fluorescence isothiocyanate (FITC)-conjugated NK1516 CP was detected in the hippocampus of mice. The NK1516 genome exhibited unique CP biosynthesis-related genes (capD, wbjC, WecB, vioB), unlike that of ATCC882. These findings suggest that E. mundtii may be a risk factor for depression.
Topics: Animals; Humans; Mice; Brain-Derived Neurotrophic Factor; Depression; Down-Regulation; Enterococcus; NF-kappa B; Serotonin
PubMed: 36758891
DOI: 10.1016/j.micinf.2023.105116 -
Veterinary World Sep 2023Many strains of probiotics have been exploited and used as animal dietary supplements for broiler production. The efficacy and survival of probiotics during production...
BACKGROUND AND AIM
Many strains of probiotics have been exploited and used as animal dietary supplements for broiler production. The efficacy and survival of probiotics during production may reflect better activities of the probiotics in the host. This study investigated the effects of freeze- and spray-drying on the survivability and properties of probiotics and their ability to improve the growth and health performance of broilers.
MATERIALS AND METHODS
Probiotic powders of four strains of lactic acid bacteria, CA4, CH33, CH24, SH8, and KKU213, were prepared using rice bran/chitosan/carboxy methyl cellulose as the carrier. The survival of each probiotic strain was investigated under stress conditions, including freeze-drying, spray-drying, and simulated gastrointestinal conditions. The body weight gain (BWG) and intestinal histomorphology were determined to assess broiler growth performance.
RESULTS
All dried probiotics yielded a high survival rate during freeze-drying (95.8-98.6%) and spray-drying (94.4-98.2%). In addition, an analysis of the main effect revealed that the effectiveness of freeze-drying was higher than that of spray-drying in minimizing the loss of cell viability. The antimicrobial activity of all immobilized dried probiotic strains against was maintained. The immobilized probiotics tolerated a low pH value of 2.0 and 0.5% (w/v) bile salt. Probiotic administration of a mixture of the five dried probiotics to 1-day-old hatched male broilers at early and late ages resulted in potential colonization in the broiler intestine, and enhancements in the BWG, lipid metabolism, and gut health (villus height and cryptal depth) were observed in the probiotic-treated groups.
CONCLUSION
The administration of three doses of the spray-dried probiotic mixture at days 15, 17, and 19 after hatching was sufficient to achieve long-term growth and health benefits in broilers. This finding might provide a cost-effective alternative to the administration of commonly used antibiotics in broiler production.
PubMed: 37859958
DOI: 10.14202/vetworld.2023.1849-1865 -
Life (Basel, Switzerland) Aug 2023This study sought to evaluate the probiotic properties and the food preservation ability of lactic acid bacteria isolates collected from the intestines of wild marine...
Selection and Characterization of Bacteriocinogenic Lactic Acid Bacteria from the Intestine of Gilthead Seabream () and Whiting Fish (): Promising Strains for Aquaculture Probiotic and Food Bio-Preservation.
This study sought to evaluate the probiotic properties and the food preservation ability of lactic acid bacteria isolates collected from the intestines of wild marine fishes (gilthead seabream () ( = 60) and whiting fish () ( = 40)) from the Mediterranean sea in the area of Mostaganem city, Algeria. Forty-two isolates were identified as: ( = 19), ( = 15), ( = 4), subp. ( = 3), and ( = 1). All isolates showed inhibition to at least one indicator strain, especially against , , , , , , and . In all collected isolates, PCR analysis of enterocin-encoding genes showed the following genes: ( = 21), 1071A/B ( = 11), ( = 8), L50A/B ( = 7), AS48 ( = 5), and ( = 1). Interestingly, 15 isolates harbored more than one gene. Antimicrobial susceptibility, phenotypic virulence, and genes encoding virulence factors were investigated by PCR. Resistance to tetracycline ( = 8: + , erythromycin ( = 7: 5 , 2 , and 1 (A/E)), ciprofloxacin ( = 1), gentamicin ( = 1: (6')-(2″)), and linezolid ( = 1) were observed. Three isolates were gelatinase producers and eight were α-hemolytic. Three and one harbored the gene. Eight isolates showing safety properties (susceptible to clinically relevant antibiotics, free of genes encoding virulence factors) were tested to select probiotic candidates. They showed high tolerance to low pH and bile salt, hydrophobicity power, and co-culture ability. The eight isolates showed important phenotypic and genotypic traits enabling them to be promising probiotic candidates or food bio-conservers and starter cultures.
PubMed: 37763237
DOI: 10.3390/life13091833 -
Metabolites Jul 2023The aim of this research was to assess the antibacterial and antioxidant properties as well as the variation in metabolites of the cell-free supernatant (CFS) produced...
The aim of this research was to assess the antibacterial and antioxidant properties as well as the variation in metabolites of the cell-free supernatant (CFS) produced by lactic acid bacteria (LAB) from local plants: ngue16, ng10, w3, and w6. The tested strains exhibited inhibitory effects against pathogens, including , , , , Typhimurium, using the agar spot assay and well diffusion method. The CFS from all four strains displayed antibacterial activity against these pathogens with minimum inhibitory concentration (MIC) values ranging from 3.12 to 12.5 mg/mL and minimal bactericidal concentration (MBC) values ranging from 6.25 to 25.0 mg/mL. Moreover, the CFS demonstrated resilience within specific pH (3-8) and temperature (60-100 °C) ranges and lost its activity when treated with enzymes, such as Proteinase K and pepsin. Furthermore, the CFS exhibited antioxidant properties as evidenced by their ability to inhibit the formation of two radicals (1,1-diphenyl-2-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) compared to the negative control, De Man, Rogosa, and Sharpe (MRS) broth. The use of proton-based nuclear magnetic resonance (H-NMR) spectroscopy revealed the presence and quantification of 48 metabolites in both the CFS and MRS broths. Principal Component Analysis (PCA) effectively differentiated between CFS and MRS broth by identifying the specific metabolites responsible for the observed differences. The partial least squares (PLS) model demonstrated a significant correlation between the metabolites in the LAB supernatant and the tested antibacterial and antioxidant activities. Notably, anserine, GABA, acetic acid, lactic acid, uracil, uridine, propylene glycol, isopropanol, serine, histidine, and indol-3-lactate were identified as the compounds contributing the most to the highest antibacterial and antioxidant activities in the supernatant. These findings suggest that the LAB strains investigated have the potential to be utilized in the production of functional foods and the development of pharmaceutical products.
PubMed: 37512555
DOI: 10.3390/metabo13070849 -
Scientific Reports Nov 2023
Author Correction: Antimicrobial resistance and whole genome sequencing of novel sequence types of Enterococcus faecalis, Enterococcus faecium, and Enterococcus durans isolated from livestock.
PubMed: 37963920
DOI: 10.1038/s41598-023-46976-2 -
Foods (Basel, Switzerland) Apr 2024, a Finnish ropy fermented milk, is traditionally manufactured through spontaneous fermentation, by mesophilic lactic acid bacteria and yeast-like fungi, or...
, a Finnish ropy fermented milk, is traditionally manufactured through spontaneous fermentation, by mesophilic lactic acid bacteria and yeast-like fungi, or back-slopping. This study evaluated four natural starters as sources of lactic acid bacteria for dairy production. Back-slopping activation of the studied samples was monitored through pH and titratable acidity measurements and enumeration of mesophilic lactic acid bacteria. Sixty lactic acid bacteria isolates were collected, molecularly identified, and assayed for acidification performance, enzymatic activities, production of exopolysaccharides (EPSs), presence of the histidine decarboxylase () gene of Gram-positive bacteria, and production of bacteriocins. A neat predominance of emerged among the isolates, followed by , , , , and . Most isolates exhibited proteolytic activity, whereas only a few enterococci showed lipase activity. Five isolates identified as , , and showed a good acidification performance. Most of the isolates tested positive for leucine arylamidase, whereas only one and two isolates were positive for valine arylamidase. A few isolates also showed a positive reaction for beta-galactosidase and alpha- and beta-glucosidase. None of the isolates produced EPSs or bacteriocins. The gene was detected in five isolates identified as and . A few and isolates for potential use as starter or adjunct cultures for dairy processing were finally identified.
PubMed: 38611419
DOI: 10.3390/foods13071115 -
ACS ES&T Engineering Oct 2023It is a long-pursued goal to develop electrified water treatment technology that can remove contaminants without byproduct formation. This study unveiled the overlooked...
It is a long-pursued goal to develop electrified water treatment technology that can remove contaminants without byproduct formation. This study unveiled the overlooked multifunctionality of electro-Fenton (EF) and induced EF (I-EF) processes to remove organics, pathogens, and phosphate in one step without halogenated byproduct formation. The EF and I-EF processes used a sacrificial anode or an induced electrode to generate Fe to activate HO produced from a gas diffusion cathode fed by naturally diffused air. We used experimental and kinetic modeling approaches to illustrate that the OH generation and radical speciation during EF were not impacted by chloride. More importantly, reactive chlorine species were quenched by HO, which eliminated the formation of halogenated byproducts. When applied in treating septic wastewater, the EF process removed >80% COD, >50% carbamazepine (as representative trace organics), and >99% phosphate at a low energy consumption of 0.37 Wh/L. The EF process also demonstrated broad-spectrum disinfection activities in removing and inactivating , , and model viruses MS2 and Phi6. In contrast to electrochemical oxidation (EO) that yielded mg/L level byproducts to achieve the same degree of treatment, EF did not generate byproducts (chlorate, perchlorate, trihalomethanes, and haloacetic acids). The I-EF carried over all the advantages of EF and exhibited even faster kinetics in disinfection and carbamazepine removal with 50-80% less sludge production. Last, using septic wastewater treatment as a technical niche, we demonstrated that iron sludge formation is predictable and manageable, clearing roadblocks toward on-site water treatment applications.
PubMed: 37854076
DOI: 10.1021/acsestengg.3c00128