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Veterinary Medicine and Science Jul 2024Bersama abyssinica Fresen is a plant that is used in folk medicine for the treatment of mastitis and other infectious diseases.
BACKGROUND
Bersama abyssinica Fresen is a plant that is used in folk medicine for the treatment of mastitis and other infectious diseases.
OBIECTIVE
The antibacterial activity of methanol crude extract of plant was evaluated against three common bacterial pathogens, including Gram positive (Staphylococcus aureus) and Gram negative (Escherichia coli and Pseudomonas aeruginosa).
METHODS
The antibacterial activities and minimum inhibitory concentration of B. abyssinica crude extracts were evaluated using agar-well diffusion and broth dilution methods according to the National Committee for Clinical Laboratory Standards (NCCLS).
RESULTS
A significant difference in the antibacterial activity of crude extracts was observed among different levels of concentration against tested isolates. A higher mean inhibition zone diameter was recorded in E. coli (29.2 ± 1.5 mm), followed by S. aureus (27.8 ± 1.1 mm) and P. aeruginosa (18.0 ± 0.7 mm) at a concentration of 100 mg/mL. The antibacterial activity of crude plant extract at 100 mg/mL was comparable with that of a standard antibiotic (27.6 ± 2.6) against S. aureus and E. coli isolates. The findings indicated that bacterial growth inhibition increased as the concentration of the crude extracts increased. E. coli and S. aureus isolates showed significantly higher susceptibilities to crude extracts than P. aeruginosa at all concentrations. The minimum inhibitory concentrations of extracts against S. aureus, E. coli and P. aeruginosa isolates were 0.78 mg/mL, 1.56 mg/mL and 1.56 mg/mL, respectively.
CONCLUSIONS
All tested pathogenic bacterial species were susceptible to plant leaf extract and broad-spectrum activity against Gram-positive and Gram-negative bacteria. The study recommends further fractionation of the B. abyssinica plant that contributes to its antibacterial activity and understands the mode of action of this plant against bacteria and other microbes.
Topics: Plant Extracts; Anti-Bacterial Agents; Microbial Sensitivity Tests; Gram-Negative Bacteria; Gram-Positive Bacteria; Escherichia coli; Staphylococcus aureus; Pseudomonas aeruginosa
PubMed: 38896065
DOI: 10.1002/vms3.1498 -
Molecules (Basel, Switzerland) May 2024Novel isoxazole-triazole conjugates have been efficiently synthesized using 3-formylchromone as starting material according to a multi-step synthetic approach. The...
Novel isoxazole-triazole conjugates have been efficiently synthesized using 3-formylchromone as starting material according to a multi-step synthetic approach. The structures of the target conjugates and intermediate products were characterized by standard spectroscopic techniques (H NMR and C NMR) and confirmed by mass spectrometry (MS). The all-synthesized compounds were screened for their antibacterial activity against three ATCC reference strains, namely ATCC 25923, ATCC BAA-44, and ATCC 25922 as well as one strain isolated from the hospital environment . The findings indicate that conjugate 7b exhibits a stronger antibacterial response against the tested ATCC 25922 and pathogenic strains compared to the standard antibiotics. Furthermore, hybrid compound proved to have a bactericidal action on the ATCC 25922 strain, as evidenced by the results of the MBC determination. Moreover, the ADMET pharmacokinetic characteristics revealed a favorable profile for the examined compound, as well as a good level of oral bioavailability. Molecular docking and molecular dynamics simulations were performed to explore the inhibition mechanism and binding energies of conjugate with the proteins of and bacterial strains. The in silico results corroborated the data observed in the in vitro evaluation for compound .
Topics: Anti-Bacterial Agents; Triazoles; Molecular Docking Simulation; Microbial Sensitivity Tests; Pseudomonas aeruginosa; Escherichia coli; Isoxazoles; Staphylococcus aureus; Drug Design; Molecular Dynamics Simulation; Molecular Structure; Structure-Activity Relationship; Computer Simulation
PubMed: 38893386
DOI: 10.3390/molecules29112510 -
Molecules (Basel, Switzerland) May 2024The human paraoxonase 2 (PON2) is the oldest member of a small family of arylesterase and lactonase enzymes, representing the first line of defense against bacterial...
The human paraoxonase 2 (PON2) is the oldest member of a small family of arylesterase and lactonase enzymes, representing the first line of defense against bacterial infections and having a major role in ROS-associated diseases such as cancer, cardiovascular diseases, neurodegeneration, and diabetes. Specific Post-Translational Modifications (PTMs) clustering nearby two residues corresponding to polymorphic sites and their impact on the catalytic activity are not yet fully understood. Thus, the goal of the present study was to develop an improved PON2 purification protocol to obtain a higher amount of protein suitable for in-depth biochemical studies and biotechnological applications. To this end, we also tested several compounds to stabilize the active monomeric form of the enzyme. Storing the enzyme at 4 °C with 30 mM Threalose had the best impact on the activity, which was preserved for at least 30 days. The catalytic parameters against the substrate 3-Oxo-dodecanoyl-Homoserine Lactone (3oxoC12-HSL) and the enzyme ability to interfere with the biofilm formation of () were determined, showing that the obtained enzyme is well suited for downstream applications. Finally, we used the purified rPON2 to detect, by the direct molecular fishing (DMF) method, new putative PON2 interactors from soluble extracts of HeLa cells.
Topics: Aryldialkylphosphatase; Humans; Proteomics; Protein Refolding; Pseudomonas aeruginosa; Enzyme Stability; Biofilms; Protein Processing, Post-Translational
PubMed: 38893310
DOI: 10.3390/molecules29112434 -
International Journal of Molecular... May 2024The pyoverdine siderophore is produced by to access iron. Its synthesis involves the complex coordination of four nonribosomal peptide synthetases (NRPSs), which are...
The pyoverdine siderophore is produced by to access iron. Its synthesis involves the complex coordination of four nonribosomal peptide synthetases (NRPSs), which are responsible for assembling the pyoverdine peptide backbone. The precise cellular organization of these NRPSs and their mechanisms of interaction remain unclear. Here, we used a combination of several single-molecule microscopy techniques to elucidate the spatial arrangement of NRPSs within pyoverdine-producing cells. Our findings reveal that PvdL differs from the three other NRPSs in terms of localization and mobility patterns. PvdL is predominantly located in the inner membrane, while the others also explore the cytoplasmic compartment. Leveraging the power of multicolor single-molecule localization, we further reveal co-localization between PvdL and the other NRPSs, suggesting a pivotal role for PvdL in orchestrating the intricate biosynthetic pathway. Our observations strongly indicates that PvdL serves as a central orchestrator in the assembly of NRPSs involved in pyoverdine biosynthesis, assuming a critical regulatory function.
Topics: Pseudomonas aeruginosa; Oligopeptides; Peptide Synthases; Bacterial Proteins; Siderophores
PubMed: 38892200
DOI: 10.3390/ijms25116013 -
International Journal of Molecular... May 2024The aim of this work was to develop and characterize a thin films composed of hyaluronic acid/ellagic acid for potential medical application. Its principal novelty,...
The aim of this work was to develop and characterize a thin films composed of hyaluronic acid/ellagic acid for potential medical application. Its principal novelty, distinct from the prior literature in terms of hyaluronic acid films supplemented with phenolic acids, resides in the predominant incorporation of ellagic acid-a distinguished compound-as the primary constituent of the films. Herein, ellagic acid was dissolved in two different solvents, i.e., acetic acid (AcOH) or sodium hydroxide (NaOH), and the surface properties of the resultant films were assessed using atomic force microscopy and contact angle measurements. Additionally, various physicochemical parameters were evaluated including moisture content, antioxidant activity, and release of ellagic acid in phosphate buffered saline. Furthermore, the evaluation of films' biocompatibility was conducted using human epidermal keratinocytes, dermal fibroblasts, and human amelanotic melanoma cells (A375 and G361), and the antimicrobial activity was elucidated accordingly against ATCC 6538 and ATCC 15442. Our results showed that the films exhibited prominent antibacterial properties particularly against , with the 80HA/20EA/AcOH film indicating the strong biocidal activity against this strain leading to a significant reduction in viable cells. Comparatively, the 50HA/50EA/AcOH film also displayed biocidal activity against . This experimental approach could be a promising technique for future applications in regenerative dermatology or novel strategies in terms of bioengineering.
Topics: Hyaluronic Acid; Humans; Staphylococcus aureus; Biocompatible Materials; Ellagic Acid; Pseudomonas aeruginosa; Anti-Bacterial Agents; Antioxidants; Fibroblasts; Keratinocytes; Microbial Sensitivity Tests; Cell Line, Tumor; Surface Properties
PubMed: 38892078
DOI: 10.3390/ijms25115891 -
International Journal of Molecular... May 2024Peptides displaying antimicrobial properties are being regarded as useful tools to evade and combat antimicrobial resistance, a major public health challenge. Here we...
Peptides displaying antimicrobial properties are being regarded as useful tools to evade and combat antimicrobial resistance, a major public health challenge. Here we have addressed dendrimers, attractive molecules in pharmaceutical innovation and development displaying broad biological activity. Triazine-based dendrimers were fully synthesized in the solid phase, and their antimicrobial activity and some insights into their mechanisms of action were explored. Triazine is present in a large number of compounds with highly diverse biological targets with broad biological activities and could be an excellent branching unit to accommodate peptides. Our results show that the novel peptide dendrimers synthesized have remarkable antimicrobial activity against Gram-negative bacteria ( and ) and suggest that they may be useful in neutralizing the effect of efflux machinery on resistance.
Topics: Dendrimers; Triazines; Microbial Sensitivity Tests; Escherichia coli; Pseudomonas aeruginosa; Antimicrobial Peptides; Anti-Bacterial Agents; Anti-Infective Agents; Antimicrobial Cationic Peptides
PubMed: 38892071
DOI: 10.3390/ijms25115883 -
Cells Jun 2024Precise control of neuronal activity is crucial for the proper functioning of neurons. How lipid homeostasis contributes to neuronal activity and how much of it is...
Precise control of neuronal activity is crucial for the proper functioning of neurons. How lipid homeostasis contributes to neuronal activity and how much of it is regulated by cells autonomously is unclear. In this study, we discovered that absence of the lipid regulator , a functional ortholog of the peroxisome proliferator-activated receptor (PPAR) in , resulted in defective pathogen avoidance behavior against (PA14). Functional NHR-49 was required in the neurons, and more specifically, in a set of oxygen-sensing body cavity neurons, URX, AQR, and PQR. We found that lowering the neuronal activity of the body cavity neurons improved avoidance in mutants. Calcium imaging in URX neurons showed that mutants displayed longer-lasting calcium transients in response to an O upshift, suggesting that excess neuronal activity leads to avoidance defects. Cell-specific rescue of NHR-49 in the body cavity neurons was sufficient to improve pathogen avoidance, as well as URX neuron calcium kinetics. Supplementation with oleic acid also improved avoidance behavior and URX calcium kinetics, suggesting that the defective calcium response in the neuron is due to lipid dysfunction. These findings highlight the role of cell-autonomous lipid regulation in neuronal physiology and immune behavior.
Topics: Animals; Caenorhabditis elegans; Lipid Metabolism; Caenorhabditis elegans Proteins; Neurons; Pseudomonas aeruginosa; Calcium; Mutation; Avoidance Learning; Receptors, Cytoplasmic and Nuclear
PubMed: 38891110
DOI: 10.3390/cells13110978 -
Applied Microbiology and Biotechnology Jun 2024Non-symbiotic N-fixation would greatly increase the versatility of N-biofertilizers for sustainable agriculture. Genetic modification of diazotrophic bacteria has...
Non-symbiotic N-fixation would greatly increase the versatility of N-biofertilizers for sustainable agriculture. Genetic modification of diazotrophic bacteria has successfully enhanced NH release. In this study, we compared the competitive fitness of A. vinelandii mutant strains, which allowed us to analyze the burden of NH release under a broad dynamic range. Long-term competition assays under regular culture conditions confirmed a large burden for NH release, exclusion by the wt strain, phenotypic instability, and loss of the ability to release NH. In contrast, co-inoculation in mild autoclaved soil showed a much longer co-existence with the wt strain and a stable NH release phenotype. All genetically modified strains increased the N content and changed its chemical speciation in the soil. This study contributes one step forward towards bridging a knowledge gap between molecular biology laboratory research and the incorporation of N from the air into the soil in a molecular species suitable for plant nutrition, a crucial requirement for developing improved bacterial inoculants for economic and environmentally sustainable agriculture. KEY POINTS: • Genetic engineering for NH excretion imposes a fitness burden on the culture medium • Large phenotypic instability for NH-excreting bacteria in culture medium • Lower fitness burden and phenotypic instability for NH-excreting bacteria in soil.
Topics: Soil Microbiology; Azotobacter vinelandii; Ammonium Compounds; Nitrogen Fixation; Nitrogen; Genetic Fitness; Phenotype; Soil; Culture Media; Genetic Engineering
PubMed: 38888816
DOI: 10.1007/s00253-024-13231-1 -
Antimicrobial Resistance and Infection... Jun 2024Stenotrophomonas maltophilia, a multidrug-resistant gram-negative bacteria (GNB), is an emerging nosocomial pathogen. This study assessed the clinical outcomes of GNB...
Gram-negative bacterial infections in surgical intensive care unit patients following abdominal surgery: high mortality associated with Stenotrophomonas maltophilia infection.
BACKGROUND
Stenotrophomonas maltophilia, a multidrug-resistant gram-negative bacteria (GNB), is an emerging nosocomial pathogen. This study assessed the clinical outcomes of GNB infections in surgical intensive care unit (SICU) patients post-abdominal surgery, focusing on the differences between S. maltophilia and other GNBs, including Pseudomonas aeruginosa.
METHODS
A retrospective study was conducted on SICU patients at Kaohsiung Chang Gung Memorial Hospital from 2010 to 2020, who developed GNB infections following abdominal surgery.
RESULTS
Of 442 patients, 237 had S. maltophilia and 205 had non-S. maltophilia GNB infections (including 81 with P. aeruginosa). The overall mortality rate was 44.5%, and S. maltophilia infection emerged as a significant contributor to the mortality rate in patients with GNB infections. S. maltophilia patients had longer mechanical ventilation and SICU stays, with a 30-day mortality rate of 35.4%, higher than the non-S. maltophilia GNB (22.9%) and P. aeruginosa (21%) groups. In-hospital mortality was also higher in the S. maltophilia group (53.2%) compared to the non-S. maltophilia GNB (34.6%) and P. aeruginosa groups (29.6%). Risk factors for acquiring S. maltophilia included a higher Sequential Organ Failure Assessment score and prior broad-spectrum antibiotics use. Older age, polymicrobial infections, and elevated bilirubin were associated with increased 30-day mortality in S. maltophilia patients.
CONCLUSION
S. maltophilia infections in post-abdominal surgery patients are linked to higher mortality than non-S. maltophilia GNB and P. aeruginosa infections, emphasizing the need for early diagnosis and treatment to improve outcomes.
Topics: Humans; Stenotrophomonas maltophilia; Gram-Negative Bacterial Infections; Male; Retrospective Studies; Female; Middle Aged; Intensive Care Units; Aged; Abdomen; Hospital Mortality; Pseudomonas aeruginosa; Adult; Cross Infection; Anti-Bacterial Agents
PubMed: 38886759
DOI: 10.1186/s13756-024-01411-7 -
BMC Complementary Medicine and Therapies Jun 2024Biofilms and oxidative stress retard wound healing. The resistance of biofilms to antibiotics has led to a search for alternative approaches in biofilm elimination....
BACKGROUND
Biofilms and oxidative stress retard wound healing. The resistance of biofilms to antibiotics has led to a search for alternative approaches in biofilm elimination. Antioxidants work synergistically with antibacterial agents against biofilms. Hence recent research has suggested plants as candidates in the development of new alternatives in biofilm treatments and as antioxidants due to the presence of phytocompounds which are responsible for their bioactivities. Hoslundia opposita Vahl is one of the plants used by traditional healers to treat wounds and other infections, this makes it a potential candidate for drug discovery hence, in this study, we investigate the antibiofilm and antioxidant activity of methanolic extract of hoslundia opposita Vahl from Uganda. We also identify phytochemicals responsible for its bioactivity.
METHOD
the plant was extracted by maceration using methanol, and the extract was investigated for antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) assay. The antibiofilm activity using microtiter plate assay (MTP) assay where the Minimum biofilm inhibitory concentration required to inhibit 50% or 90% of the biofilm (MBIC and MBIC) and Minimum biofilm eradication concentration required to remove 50% or 90% of the biofilm (MBEC and MBEC) were measured. It was further analysed for its phytochemical composition using quantitative screening, as well as Gas chromatography-mass spectrometry (GC-MS) and Liquid chromatography mass-spectrometry (LC-MS).
RESULTS
H. Opposita Vahl extract showed good antioxidant activity with of 249.6 mg/mL. It inhibited the growth of P. aeruginosa and S. aureus biofilms with MBIC of 28.37 mg/mL and 10 mg/mL, respectively. It showed the ability to eradicate P. aeruginosa and S. aureus biofilms with MBEC of 23.85 and 39.01 mg/mL respectively. Phytochemical analysis revealed the presence of alkaloids, tannins, flavonoids, and phenols. GC-MS analysis revealed 122 compounds in the extract of which, 23 have evidence of antioxidant or antibiofilm activity in literature. The most abundant compounds were; 1,4- Citric acid, Tetracontane-1,40-diol (43.43.3%, 1, Olean-12-en-28-oic acid, 3-hydroxy-, methyl ester, (3.beta) (15.36%) 9-Octadecenamide (12.50%), Squalene (11.85%) Palmitic Acid 4TMS (11.28%), and alpha Amyrin (11.27%). The LC-MS identified 115 and 57 compounds in multiple reaction mode (MRM) and scan modes respectively.
CONCLUSION
H. opposita Vahl showed antibiofilm and antioxidant activity due to bioactive compounds identified, hence the study justifies its use for wound healing. It can be utilised in further development of new drugs as antibiofilm and antioxidants.
Topics: Biofilms; Antioxidants; Plant Extracts; Wound Healing; Anti-Bacterial Agents; Pseudomonas aeruginosa; Microbial Sensitivity Tests; Uganda; Staphylococcus aureus; Humans; Phytochemicals
PubMed: 38886717
DOI: 10.1186/s12906-024-04540-z