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Microbiology Resource Announcements Jun 2024is highly virulent but often misidentified in clinical settings. The entire genome sequence of a metallo-β-lactamase-producing strain from a clinical specimen has...
is highly virulent but often misidentified in clinical settings. The entire genome sequence of a metallo-β-lactamase-producing strain from a clinical specimen has been presented in this study. The genome comprised a single chromosome of 4.89 Mbp with 61.6% G + C content.
PubMed: 38916297
DOI: 10.1128/mra.00010-24 -
Infection and Drug Resistance 2024Hospital wastewater (HWW) promotes the spread of carbapenem resistance genes (CRGs). carry a large number of CRGs in HWW, they may play a role as a suitable reservoir...
BACKGROUND
Hospital wastewater (HWW) promotes the spread of carbapenem resistance genes (CRGs). carry a large number of CRGs in HWW, they may play a role as a suitable reservoir for CRGs, while resistomes in HWW are still poorly characterized regarding carbapenem resistant . Thus, the aim of the study was to evaluate the molecular epidemiological characteristics of carbapenem resistant in HWW.
METHODS
A total of 33 carbapenem resistant were isolated from HWW. Antimicrobial susceptibility testing and polymerase chain reaction (PCR) were used to assess the antimicrobial resistance profiles. Molecular typing was performed using enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) and multilocus sequence typing (MLST). The horizontal transmission mode of was explored through conjugation and transformation experiments. The stability of -IncP-6 plasmids was assessed through plasmid stability and in vitro competition test. The PCR mapping method was used to investigate the structural diversity of .
RESULTS
The detection rates of and in were 97.0% and 39.4% respectively. were grouped into 13 clusters by ERIC-PCR and 12 STs by MLST. were grouped into 11 clusters by ERIC-PCR and 4 STs by MLST. 56.3% were located on mobilizable IncP-6 plasmids. -IncP-6 plasmid showed high stability and low cost fitness.
CONCLUSION
Carbapenem resistant from HWW mainly carried , which exhibited great structural diversity. might serve as reservoirs for and might spread mainly through transformation in HWW.
PubMed: 38912216
DOI: 10.2147/IDR.S460715 -
Nutrients May 2024The imbalance of gut microbiota is an important factor leading to inflammatory bowel disease (IBD). Diffusible signal factor (DSF) is a novel quorum-sensing signal that...
The imbalance of gut microbiota is an important factor leading to inflammatory bowel disease (IBD). Diffusible signal factor (DSF) is a novel quorum-sensing signal that regulates bacterial growth, metabolism, pathogenicity, and host immune response. This study aimed to explore the therapeutic effect and underlying mechanisms of DSF in a zebrafish colitis model induced by sodium dextran sulfate (DSS). The results showed that intake of DSF can significantly improve intestinal symptoms in the zebrafish colitis model, including ameliorating the shortening of the intestine, reducing the increase in the goblet cell number, and restoring intestinal pathological damage. DSF inhibited the upregulation of inflammation-related genes and promoted the expression of claudin1 and occludin1 to protect the tightness of intestinal tissue. The gut microbiome analysis demonstrated that DSF treatment helped the gut microbiota of the zebrafish colitis model recover to normal at the phylum and genus levels, especially in terms of pathogenic bacteria; DSF treatment downregulated the relative abundance of and , and it was confirmed in microbiological experiments that DSF could effectively inhibit the colonization and infection of these two pathogens in the intestine. This study suggests that DSF can alleviate colitis by inhibiting the proliferation of intestinal pathogens and inflammatory responses in the intestine. Therefore, DSF has the potential to become a dietary supplement that assists in the antibiotic and nutritional treatment of IBD.
Topics: Animals; Zebrafish; Dextran Sulfate; Gastrointestinal Microbiome; Colitis; Disease Models, Animal; Quorum Sensing; Intestines; Aeromonas hydrophila; Inflammation; Staphylococcus aureus
PubMed: 38892496
DOI: 10.3390/nu16111562 -
BMC Research Notes Jun 2024The aim of this study was to quantify and identify metabolites of Ice Nucleation Active (INA) bacteria as an anti-biofilm agent against biofilms of fish pathogens such...
OBJECTIVES
The aim of this study was to quantify and identify metabolites of Ice Nucleation Active (INA) bacteria as an anti-biofilm agent against biofilms of fish pathogens such as Aeromonas hydrophila and Streptococcus agalactiae.
RESULTS
Ice nucleation active bacteria, which have the ability to catalyze ice nucleation, isolated from rainwater in previous studies, were used. All INA isolates were tested in several assays, including the antimicrobial test, which uses streptomycin as the positive control and none of the isolates were found positive in the antimicrobial test. As for the quorum quenching assay, it was found that four out of ten isolates were able to disturb the communication system in Chromobacterium violaceum wild type, which was used as the indicator bacteria. On the next assay, all ten isolates were tested for Biofilm Inhibition and Destruction and showed anti-biofilm activity with the highest percentage inhibition of 33.49% by isolate A40 against A. hydrophila and 77.26% by isolate A19 against S. agalactiae. C1 performed the highest destruction against A. hydrophila and S. agalactiae, with percentages of 32.11% and 51.88%, respectively. As for the GC-MS analysis, supernatants of INA bacteria contain bioactive compounds such as sarcosine and fatty acids, which are known to have antibiofilm activity against several biofilm-forming bacteria. Through 16s rRNA sequencing, identified bacteria are from the Pantoea, Enterobacter, and Acinetobacter genera. As for the conclusion, ice nucleation active bacteria metabolites tested showed positive results against pathogenic bacteria Aeromonas hydrophila and Streptococcus agalactiae in destructing and inhibiting biofilm growth.
Topics: Biofilms; Aeromonas hydrophila; Streptococcus agalactiae; Anti-Bacterial Agents; Aquaculture; Fish Diseases; Animals; RNA, Ribosomal, 16S; Microbial Sensitivity Tests; Gram-Negative Bacterial Infections; Ice; Streptococcal Infections; Quorum Sensing
PubMed: 38886828
DOI: 10.1186/s13104-024-06821-9 -
Virulence Dec 2024The global surge in multidrug-resistant bacteria owing to antibiotic misuse and overuse poses considerable risks to human and animal health. With existing antibiotics...
The global surge in multidrug-resistant bacteria owing to antibiotic misuse and overuse poses considerable risks to human and animal health. With existing antibiotics losing their effectiveness and the protracted process of developing new antibiotics, urgent alternatives are imperative to curb disease spread. Notably, improving the bactericidal effect of antibiotics by using non-antibiotic substances has emerged as a viable strategy. Although reduced nicotinamide adenine dinucleotide (NADH) may play a crucial role in regulating bacterial resistance, studies examining how the change of metabolic profile and bacterial resistance following by exogenous administration are scarce. Therefore, this study aimed to elucidate the metabolic changes that occur in (), which exhibits resistance to various antibiotics, following the exogenous addition of NADH using metabolomics. The effects of these alterations on the bactericidal activity of neomycin were investigated. NADH enhanced the effectiveness of aminoglycoside antibiotics against ATCC15947, achieving bacterial eradication at low doses. Metabolomic analysis revealed that NADH reprogrammed the ATCC15947 metabolic profile by promoting purine metabolism and energy metabolism, yielding increased adenosine triphosphate (ATP) levels. Increased ATP levels played a crucial role in enhancing the bactericidal effects of neomycin. Moreover, exogenous NADH promoted the bactericidal efficacy of tetracyclines and chloramphenicols. NADH in combination with neomycin was effective against other clinically resistant bacteria, including , methicillin-resistant , and . These results may facilitate the development of effective approaches for preventing and managing -induced infections and multidrug resistance in aquaculture and clinical settings.
Topics: Edwardsiella tarda; Anti-Bacterial Agents; NAD; Aminoglycosides; Animals; Fish Diseases; Microbial Sensitivity Tests; Enterobacteriaceae Infections; Adenosine Triphosphate; Neomycin; Drug Synergism; Metabolomics; Drug Resistance, Multiple, Bacterial
PubMed: 38884466
DOI: 10.1080/21505594.2024.2367647 -
One Step Rapid Sensitive Method for the Diagnosis of Hemolysin Gene of by Polymerase Chain Reaction.Journal of Pharmacy & Bioallied Sciences Apr 2024is a Gram-negative bacterium that has been linked to serious illnesses in both humans and animals. The presence of hemolysin, a virulence factor, is critical in the...
is a Gram-negative bacterium that has been linked to serious illnesses in both humans and animals. The presence of hemolysin, a virulence factor, is critical in the development of -related illnesses. As a result, precise and timely detection of the hemolysin gene is critical for efficient diagnosis and prevention of many illnesses. The PCR is used in this study to detect the hemolysin gene of in a novel, fast, and highly sensitive one-step technique. Specific primers were constructed to amplify a conserved area within the hemolysin gene to achieve both specificity as well as sensitivity. The PCR assay was rigorously optimized, taking temperature, primer concentration, and reaction time into account, in order to maximize the efficiency and reliability of this method. In conclusion, this method's simplicity, sensitivity, and specificity make it highly promising for regular diagnostic applications. Its application would allow for the early detection of infections, allowing for more effective treatment and control methods.
PubMed: 38882782
DOI: 10.4103/jpbs.jpbs_571_23 -
Scientific Reports Jun 2024In this study, 80 catfish fillets were randomly collected from Egyptian local markets and retailers. The samples included 20 African catfish (Clarias gariepinus), 20...
In this study, 80 catfish fillets were randomly collected from Egyptian local markets and retailers. The samples included 20 African catfish (Clarias gariepinus), 20 bayad (Bagrus bajad), and 40 pangasius catfish (Pangasianodon hypophthalmus) fillets. Pangasianodon hypophthalmus fillet samples were divided into 20 white basa and 20 red basa fillets. We conducted a microbiological analysis of catfish fillet samples, evaluating mesophilic aerobic bacteria, psychrophilic aerobic bacteria, HS-producing bacteria, Staphylococcus spp., Enterobacteriaceae, Coliforms, and fecal Coliform counts. Additionally, we identified the existence of Salmonella spp., Vibrio spp., Yersinia spp., Escherichia spp., Aeromonas spp., and Pseudomonas spp. in the catfish fillet samples. In our study, the psychrophilic bacterial counts in Bagrus bajad (5.21 log CFU/g) were found to be higher compared to the counts in Clarias gariepinus (4.31 log CFU/g) and Pangasianodon hypophthalmus (3.89-4.7 log CFU/g). The fecal Coliform in Clarias gariepinus fillets was significantly higher than in other catfish fillets. We isolated Escherichia coli, Escherichia fergusonii, Aeromonas hydrophila, and Pseudomonas luteola from the catfish fillets, while no Salmonella spp., Vibrio spp., or Yersinia spp. were detected. These isolates were identified using 16S rRNA sequencing and phylogenetic analysis. Furthermore, ten Escherichia spp. were serologically identified, revealing that O26 and O78 were the most commonly occurring serotypes. This study highlights the microbiological analysis conducted on catfish fillets and concludes that the fillet samples from these catfish were of superior quality and deemed acceptable for human consumption.
Topics: Animals; Catfishes; Food Microbiology; Bacteria; Seafood
PubMed: 38858383
DOI: 10.1038/s41598-024-62730-8 -
Juntendo Iji Zasshi = Juntendo Medical... 2023species are Gram-negative rods known to cause infections such as gastroenteritis, bacteremia and wound infections. Colistin is one of few treatments for...
species are Gram-negative rods known to cause infections such as gastroenteritis, bacteremia and wound infections. Colistin is one of few treatments for multidrug-resistant Gram-negative bacteria. However, colistin-resistant bacteria carrying the mobilized colistin resistance () gene are a threat in healthcare settings worldwide. In recent years, colistin-resistant species have been detected in environmental and clinical samples. We analyzed the genomic characteristics of one highly colistin-resistant isolated from a blood sample in Nepal, which harbored four novel genes on its chromosome. Our study strongly suggests that is a reservoir of colistin-resistant genes. Inappropriate use of drugs in medicine and food production should be reduced and continued global surveillance for colistin-resistant bacteria is necessary.
PubMed: 38855938
DOI: 10.14789/jmj.JMJ22-0047-R -
Ecotoxicology and Environmental Safety Jul 2024This study aimed to evaluate the effect of adding liquid extract of algae (Hypnea musciformis, Grateloupia acuminata, and Sargassum muticum) (HGS) and Magnesium oxide...
Synergistic effect of green synthesis magnesium oxide nanoparticles and seaweed extract on improving water quality, health benefits, and disease resistance in Nile tilapia.
This study aimed to evaluate the effect of adding liquid extract of algae (Hypnea musciformis, Grateloupia acuminata, and Sargassum muticum) (HGS) and Magnesium oxide nanoparticles (MgO NPs) using this extract to rear water of Oreochromis niloticus, on improving culture water indices, growth performance, digestive enzyme, hemato-biochemical characters, immune, antioxidative responses, and resistance after challenged by Aeromonas hydrophila with specific refer to the potential role of the mixture in vitro as resistance against three strains bacteria (Aeromonas sobria, Pseudomonas fluorescens, P. aeruginosa) and one parasite (Cichlidogyrus tilapia). The first group represented control, HGS0, whereas the other group, HGS5, HGS10, and HGS15 mL of liquid extract, as well as all groups with 7.5 μg mL MgO-NPs added to culture water of O. niloticus, for 60 days. Data showed that increasing levels at HGS 10 and HGS15 mL in to-culture water significantly enhanced growth-stimulating digestive enzyme activity and a significantly improved survival rate of O. niloticus after being challenged with A. hydrophila than in the control group. The total viability, coliform, fecal coliform count, and heavy metal in muscle partially decreased at HGS 10 and HGS15 mL than in the control group. Correspondingly, the highest positive effect on hemato-biochemical indices was noticed at levels HGS 10 and HGS15 mL. Fish noticed an improvement in immune and antioxidant indices compared to control groups partially at HGS 10 and HGS15 mL. Interestingly, fish cultured in rearing water with the mixture provided downregulated the related inflammatory genes (HSP70, TNF, IL-1β, and IL-8) partially at HGS15 mL. In vitro, the mixture showed positive efficiency as an antibacterial and partially antiparasitic at HGS 10 and HGS15 mL. This study proposes utilizing a mixture of (HGS) and (MgO-NPs) with optimum levels of 10-15 mL in cultured water to improve water indices, growth, health status, and increased resistance of O. niloticus against bacterial and parasitic infection.
Topics: Animals; Magnesium Oxide; Cichlids; Disease Resistance; Water Quality; Seaweed; Fish Diseases; Plant Extracts; Nanoparticles; Green Chemistry Technology; Metal Nanoparticles; Aeromonas hydrophila; Sargassum
PubMed: 38843743
DOI: 10.1016/j.ecoenv.2024.116522 -
BMC Veterinary Research Jun 2024The liver-expressed antimicrobial peptide 2 (LEAP2) plays a pivotal role in the host's immune response against pathogenic microorganisms. Numerous such antimicrobial...
BACKGROUND
The liver-expressed antimicrobial peptide 2 (LEAP2) plays a pivotal role in the host's immune response against pathogenic microorganisms. Numerous such antimicrobial peptides have recently been shown to mitigate infection risk in fish, and studying those harboured by the economically important fish Acrossocheilus fasciatus is imperative for enhancing its immune responses against pathogenic microorganisms. In this study, we cloned and sequenced LEAP2 cDNA from A. fasciatus to examine its expression in immune tissues and investigate the structure-activity relationships of its intramolecular disulphide bonds.
RESULTS
The predicted amino acid sequence of A. fasciatus LEAP2 was found to include a signal peptide, pro-domain, and mature peptide. Sequence analysis indicated that A. fasciatus LEAP2 is a member of the fish LEAP2A cluster and is closely related to Cyprinus carpio LEAP2A. A. fasciatus LEAP2 transcripts were expressed in various tissues, with the head kidney exhibiting the highest mRNA levels. Upon exposure to Aeromonas hydrophila infection, LEAP2 expression was significantly upregulated in the liver, head kidney, and spleen. A mature peptide of A. fasciatus LEAP2, consisting of two disulphide bonds (Af-LEAP2-cys), and a linear form of the LEAP2 mature peptide (Af-LEAP2) were chemically synthesised. The circular dichroism spectroscopy result shows differences between the secondary structures of Af-LEAP2 and Af-LEAP2-cys, with a lower proportion of alpha helix and a higher proportion of random coil in Af-LEAP2. Af-LEAP2 exhibited potent antimicrobial activity against most tested bacteria, including Acinetobacter guillouiae, Pseudomonas aeruginosa, Staphylococcus saprophyticus, and Staphylococcus warneri. In contrast, Af-LEAP2-cys demonstrated weak or no antibacterial activity against the tested bacteria. Af-LEAP2 had a disruptive effect on bacterial cell membrane integrity, whereas Af-LEAP2-cys did not exhibit this effect. Additionally, neither Af-LEAP2 nor Af-LEAP2-cys displayed any observable ability to hydrolyse the genomic DNA of P. aeruginosa.
CONCLUSIONS
Our study provides clear evidence that linear LEAP2 exhibits better antibacterial activity than oxidised LEAP2, thereby confirming, for the first time, this phenomenon in fish.
Topics: Animals; Structure-Activity Relationship; Amino Acid Sequence; Fish Diseases; Antimicrobial Peptides; Fish Proteins; Disulfides; Phylogeny; Aeromonas hydrophila; Base Sequence
PubMed: 38835040
DOI: 10.1186/s12917-024-04106-8