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1.
Microb Pathog ; 191: 106659, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38701959

ABSTRACT

There is an increasing focus on genetically altering Paulownia trees to enhance their resistance against fungal infections, given their rapid growth and quality wood production. The aim of this research was to establish a technique for incorporating two antimicrobial thionin genes, namely thionin-60 (thio-60) and thionin-63 (thio-63), into Paulownia tomentosa and Paulownia hybrid 9501 through the utilization of chitosan nanoparticles. The outcomes revealed the successful gene transfer into Paulownia trees utilizing chitosan nanoparticles. The effectiveness of thionin proteins against plant pathogens Fusarium and Aspergillus was examined, with a specific focus on Fusarium equiseti due to limited available data. In non-transgenic Paulownia species, the leaf weight inhibition percentage varied from 25 to 36 %, whereas in transgenic species, it ranged from 22 to 7 %. In general, Paulownia species expressing thio-60 displayed increased resistance to F. equiseti, while those expressing thio-63 exhibited heightened resistance to A. niger infection. The thionin proteins displayed a strong affinity for the phospholipid bilayer of the fungal cell membrane, demonstrating their capability to disrupt its structure. The transgenic plants created through this technique showed increased resistance to fungal infections. Thionin-60 demonstrated superior antifungal properties in comparison to thio-63, being more effective at disturbing the fungal cell membrane. These findings indicate that thio-60 holds potential as a novel antifungal agent and presents a promising approach for enhancing the antimicrobial traits of genetically modified Paulownia trees.

2.
World J Microbiol Biotechnol ; 40(1): 10, 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-37947912

ABSTRACT

Melanin is a brown-black pigment with significant roles in various biological processes. The tyrosinase enzyme catalyzes the conversion of tyrosine to melanin and has promising uses in the pharmaceutical and biotechnology sectors. This research aims to purify and immobilize the tyrosinase enzyme from Pseudomonas sp. EG22 using cellulose-coated magnetic nanoparticles. Various techniques were utilized to examine the synthesized nanoparticles, which exhibited a spherical shape with an average diameter of 12 nm and a negative surface potential of - 55.7 mV with a polydispersity index (PDI) of 0.260. Comparing the immobilized magnetic tyrosinase enzyme with the free enzyme, the study's findings showed that the immobilized tyrosinase enzyme had optimal activity at a pH of 6 and a temperature of 35 °C, and its activity increased as the concentration of tyrosine increased. The study investigated the antibacterial and anticancer bioactivity of the enzyme's melanin product and found that it exhibited potential antibacterial activity against a multi-drug resistant strain including S. aureus and E. coli. The produced melanin also demonstrated the potential to decrease cell survival and induce apoptosis in initiation cells.


Subject(s)
Magnetite Nanoparticles , Monophenol Monooxygenase , Melanins , Cellulose , Magnetite Nanoparticles/chemistry , Pseudomonas , Escherichia coli , Staphylococcus aureus , Enzymes, Immobilized/chemistry , Tyrosine , Anti-Bacterial Agents/pharmacology
3.
Int J Mol Sci ; 24(19)2023 Sep 30.
Article in English | MEDLINE | ID: mdl-37834231

ABSTRACT

The challenge of rapidly diagnosing myocardial ischemia in unstable angina (UA) patients presenting to the Emergency Department (ED) is due to a lack of sensitive blood biomarkers. This has prompted an investigation into microRNAs (miRNAs) related to cardiac-derived Nourin for potential diagnostic application. The Nourin protein is rapidly expressed in patients with acute coronary syndrome (ACS) (UA and acute myocardial infarction (AMI)). MicroRNAs regulate gene expression through mRNA binding and, thus, may represent potential biomarkers. We initially identified miR-137 and miR-106b and conducted a clinical validation, which demonstrated that they were highly upregulated in ACS patients, but not in healthy subjects and non-ACS controls. Using integrated comprehensive bioinformatics analysis, the present study confirms that the Nourin protein targets miR-137 and miR-106b, which are linked to myocardial ischemia and inflammation associated with ACS. Molecular docking demonstrated robust interactions between the Nourin protein and miR137/hsa-miR-106b, involving hydrogen bonds and hydrophobic interactions, with -10 kcal/mol binding energy. I-TASSER generated Nourin analogs, with the top 10 chosen for structural insights. Antigenic regions and MHCII epitopes within the Nourin SPGADGNGGEAMPGG sequence showed strong binding to HLA-DR/DQ alleles. The Cytoscape network revealed interactions of -miR137/hsa-miR--106b and Phosphatase and tensin homolog (PTEN) in myocardial ischemia. RNA Composer predicted the secondary structure of miR-106b. Schrödinger software identified key Nourin-RNA interactions critical for complex stability. The study identifies miR-137 and miR-106b as potential ACS diagnostic and therapeutic targets. This research underscores the potential of miRNAs targeting Nourin for precision ACS intervention. The analysis leverages RNA Composer, Schrödinger, and I-TASSER tools to explore interactions and structural insights. Robust Nourin-miRNA interactions are established, bolstering the case for miRNA-based interventions in ischemic injury. In conclusion, the study contributes to UA and AMI diagnosis strategies through bioinformatics-guided exploration of Nourin-targeting miRNAs. Supported by comprehensive molecular analysis, the hypoxia-induced miR-137 for cell apoptosis (a marker of cell damage) and the inflammation-induced miR-106b (a marker of inflammation) confirmed their potential clinical use as diagnostic biomarkers. This research reinforces the growing role of miR-137/hsa-miR-106b in the early diagnosis of myocardial ischemia in unstable angina patients.


Subject(s)
Acute Coronary Syndrome , Coronary Artery Disease , MicroRNAs , Myocardial Infarction , Humans , Molecular Docking Simulation , MicroRNAs/metabolism , Angina, Unstable/diagnosis , Angina, Unstable/genetics , Myocardial Infarction/diagnosis , Myocardial Infarction/genetics , Biomarkers , Inflammation/metabolism
6.
World J Microbiol Biotechnol ; 38(6): 102, 2022 Apr 29.
Article in English | MEDLINE | ID: mdl-35486219

ABSTRACT

Antibiotic resistance represents the main challenge of Helicobacter pylori infection worldwide. This study investigates the potential bactericidal effects of fosfomycin combinations with clarithromycin, metronidazole, ciprofloxacin, amoxicillin, rifampicin, and doxycycline against thirty-six H. pylori strains using the checkerboard and time-kill assay methods. The results showed that ≥ 50% of the strains were resistant to the six antibiotics. Remarkably, only six strains exerted resistance to these antibiotics, with the minimum inhibitory concentrations (MICs) ranges of (3.2-12.8 mg/l), (32-256 mg/l), (3.2-51.2 mg/l), (3.2-25.6 mg/l), (1.6-3.2 mg/l), and (25.6 > 51.2 mg/l), respectively. The seven antibiotics were evaluated through in silico studies for their permeability and ability to bind UDP-N-acetylglucosamine1-carboxyvinyltransferase (MurA) of H. pylori. The results indicated that fosfomycin exhibited the highest predicted membrane permeability (membrane ∆G insert = - 37.54 kcal/mol) and binding affinity (docking score = - 5.310 kcal/mol) for H. pylori MurA, compared to other tested antibiotics. The combinations of fosfomycin with these antibiotics exerted synergistic interactions (Fractional inhibitory concentration, FIC index < 1) against the six strains. Importantly, the combinations of fosfomycin with clarithromycin, doxycycline and rifampicin achieved bactericidal effects (reduction ≥ 3.0 Log10 cfu/ml) against the most resistant H. pylori strain. Notably, these effects increased with presence of metronidazole, which enhanced the activity of the fosfomycin combination with amoxicillin from a weak inhibition to bactericidal effect. This study provides evidence that the combination of fosfomycin with either clarithromycin, amoxicillin, doxycycline, or rifampicin (especially with the presence of metronidazole) could be a promising option for treating MDR H. pylori infection.


Subject(s)
Fosfomycin , Helicobacter Infections , Helicobacter pylori , Amoxicillin/pharmacology , Anti-Bacterial Agents/pharmacology , Clarithromycin/pharmacology , Doxycycline/pharmacology , Fosfomycin/pharmacology , Helicobacter Infections/drug therapy , Humans , Metronidazole/pharmacology , Rifampin/pharmacology
7.
Int Microbiol ; 25(3): 427-446, 2022 Aug.
Article in English | MEDLINE | ID: mdl-34822035

ABSTRACT

One mechanism of ciprofloxacin resistance is attributed to chromosomal DNA-encoded efflux pumps such as the MepA and NorB proteins. The goal of this research is to find a way to bypass Staphylococcus aureus' efflux pumps. Because of its high membrane permeability and low association with NorB and MepA efflux proteins, a liposome-encapsulating antibiotic is one of the promising, cost-effective drug carriers and coating mechanisms for overcoming active transport of methicillin-resistant S. aureus (MRSA) multidrug-resistant efflux protein . The calculated "Log Perm RRCK" membrane permeability values of 1,2-distearoyl-sn-glycerol-3-phosphocholine (DSPC) ciprofloxacin liposome-encapsulated (CFL) showed a lower negative value of - 4,652 cm/s and greater membrane permeability than ciprofloxacin free (CPF). The results of RT-qPCR showed that cationic liposomes containing ciprofloxacin in liposome-encapsulated form (CFL) improved CPF antibacterial activity and affinity for negatively charged bacterial cell surface membrane in comparison to free drug and liposome, as it overcame several resistance mechanisms and reduced the expression of efflux pumps. Ciprofloxacin liposome-encapsulated (CFL) is therefore more effective than ciprofloxacin alone. Liposomes can be combined with a variety of drugs that interact with bacterial cell efflux pumps to maintain high sustained levels of antibiotics in bacterial cells.


Subject(s)
Methicillin-Resistant Staphylococcus aureus , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/metabolism , Ciprofloxacin/metabolism , Ciprofloxacin/pharmacology , Liposomes/metabolism , Liposomes/pharmacology , Microbial Sensitivity Tests , Multidrug Resistance-Associated Proteins/metabolism , Multidrug Resistance-Associated Proteins/pharmacology
8.
World J Microbiol Biotechnol ; 37(11): 191, 2021 Oct 11.
Article in English | MEDLINE | ID: mdl-34632522

ABSTRACT

The resistance of Candida albicans to azole drugs represents a great global challenge. This study investigates the potential fungicidal effects of atorvastatin (ATO) combinations with fluconazole (FLU), itraconazole (ITR), ketoconazole (KET) and voriconazole (VOR) against thirty-four multidrug-resistant (MDR) C. albicans using checkerboard and time-kill methods. Results showed that 94.12% of these isolates were MDR to ≥ two azole drugs, whereas 5.88% of them were susceptible to azole drugs. The tested isolates exhibited high resistance rates to FLU (58.82%), ITR (52.94%), VOR (47.06%) and KET (35.29%), whereas only three representative (8.82%) isolates were resistant to all tested azoles. Remarkably, the inhibition zones of these isolates were increased at least twofold with the presence of ATO, which interacted in a synergistic (FIC index ≤ 0.5) manner with tested azoles. In silico docking study of ATO and the four azole drugs were performed against the Lanosterol 14-alpha demethylase enzyme (ERG11) of C. albicans. Results showed that the mechanism of action of ATO against C. albicans is similar to that of azole compounds, with a docking score (-4.901) lower than azole drugs (≥5.0) due to the formation a single H-bond with Asp 225 and a pi-pi interaction with Thr 229. Importantly, ATO combinations with ITR, VOR and KET achieved fungicidal effects (≥ 3 Log10 cfu/ml reduction) against the representative isolates, whereas a fungistatic effect (≤ 3 Log10 cfu/ml reduction) was observed with FLU combination. Thus, the combination of ATO with azole drugs could be promising options for treating C. albicans infection.


Subject(s)
Atorvastatin/pharmacology , Azoles/pharmacology , Candida albicans/drug effects , Drug Resistance, Multiple, Fungal/drug effects , Fungicides, Industrial/pharmacology , Animals , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Atorvastatin/chemistry , Atorvastatin/therapeutic use , Azoles/chemistry , Azoles/therapeutic use , Candidiasis/drug therapy , Fluconazole/pharmacology , Fluconazole/therapeutic use , Fungicides, Industrial/chemistry , Fungicides, Industrial/therapeutic use , Humans , Itraconazole/pharmacology , Itraconazole/therapeutic use , Ketoconazole/pharmacology , Ketoconazole/therapeutic use , Kinetics , Microbial Sensitivity Tests , Molecular Docking Simulation , Voriconazole/pharmacology , Voriconazole/therapeutic use
9.
Antibiotics (Basel) ; 10(7)2021 Jun 22.
Article in English | MEDLINE | ID: mdl-34206211

ABSTRACT

COVID-19 is a pandemic disease caused by the SARS-CoV-2, which continues to cause global health and economic problems since emerging in China in late 2019. Until now, there are no standard antiviral treatments. Thus, several strategies were adopted to minimize virus transmission, such as social distancing, face covering protection and hand hygiene. Rhamnolipids are glycolipids produced formally by Pseudomonas aeruginosa and as biosurfactants, they were shown to have broad antimicrobial activity. In this study, we investigated the antimicrobial activity of rhamnolipids against selected multidrug resistant bacteria and SARS-CoV-2. Rhamnolipids were produced by growing Pseudomonas aeruginosa strain LeS3 in a new medium formulated from chicken carcass soup. The isolated rhamnolipids were characterized for their molecular composition, formulated into nano-micelles, and the antibacterial activity of the nano-micelles was demonstrated in vitro against both Gram-negative and Gram-positive drug resistant bacteria. In silico studies docking rhamnolipids to structural and non-structural proteins of SARS-CoV-2 was also performed. We demonstrated the efficient and specific interaction of rhamnolipids with the active sites of these proteins. Additionally, the computational studies suggested that rhamnolipids have membrane permeability activity. Thus, the obtained results indicate that SARS-CoV-2 could be another target of rhamnolipids and could find utility in the fight against COVID-19, a future perspective to be considered.

10.
Nat Prod Res ; 35(23): 5364-5368, 2021 Dec.
Article in English | MEDLINE | ID: mdl-32375513

ABSTRACT

In current study, we studied the phytochemicals of Cullen corylifolium (fruits) in which we identify twenty compounds, including two coumarins (1 and 2), three coumestans (3-5), fourchalcone (6-9), three dihydroflavones (10-12), four isoflavones (13-16), one flavonoid (17) and three meroterpenes (18-20). Among these, compounds 4, 5 and 12 were isolated from C. corylifolium for the first time. The ferroptosis inhibitory effects of the isolated phytochemicals were assessed using erastin-exposed HT22 mouse hippocampal cells. Compounds 3 and 18 showed the most potent inhibition with the IC50 values of 5.21 µM and 5.41 µM, respectively. Moreover, molecular docking study showed that compound 3 possessed tremendous inhibitory affinity for human 5-lipoxygenase (5-LOX) and Kelch-like ECH-related protein 1: nuclear factor erythroid 2-related factor 2 (Keap1-Nrf2) protein-protein interactions, two important ferroptosis-related targets. These findings indicate that compound 3 (psoralidin) may be a potential therapeutic agent for the treatment of ferroptosis-related diseases.


Subject(s)
Ferroptosis , NF-E2-Related Factor 2 , Animals , Fruit/metabolism , Kelch-Like ECH-Associated Protein 1/metabolism , Mice , Molecular Docking Simulation , NF-E2-Related Factor 2/metabolism
11.
Int J Nanomedicine ; 15: 2699-2715, 2020.
Article in English | MEDLINE | ID: mdl-32368050

ABSTRACT

PURPOSE: Current direct-acting antiviral agents for treatment of hepatitis C virus genotype 4a (HCV-4a) have been reported to cause adverse effects, and therefore less toxic antivirals are needed. This study investigated the role of curcumin chitosan (CuCs) nanocomposite as a potential anti-HCV-4a agent in human hepatoma cells Huh7. METHODS: Docking of curcumin and CuCs nanocomposite and binding energy calculations were carried out. Chitosan nanoparticles (CsNPs) and CuCs nanocomposite were prepared with an ionic gelation method and characterized with TEM, zeta size and potential, and HPLC to calculate encapsulation efficiency. Cytotoxicity studies were performed on Huh7 cells using MTT assay and confirmed with cellular and molecular assays. Anti-HCV-4a activity was determined using real-time PCR and Western blot. RESULTS: The strength of binding interactions between protein ligand complexes gave scores with NS3 protease, NS5A polymerase, and NS5B polymerase of -124.91, -159.02, and -129.16, for curcumin respectively, and -68.51, -54.52, and -157.63 for CuCs nanocomposite, respectively. CuCs nanocomposite was prepared at sizes 29-39.5 nm and charges of 33 mV. HPLC detected 4% of curcumin encapsulated into CsNPs. IC50 was 8 µg/mL for curcumin and 25 µg/mL for the nanocomposite on Huh7 but was 25.8 µg/mL and 34 µg/mL on WISH cells. CsNPs had no cytotoxic effect on tested cell lines. Apoptotic genes' expression revealed the caspase-dependent pathway mechanism. CsNPs and CuCs nanocomposite demonstrated 100% inhibition of viral entry and replication, which was confirmed with HCV core protein expression. CONCLUSION: CuCs nanocomposite inhibited HCV-4a entry and replication compared to curcumin alone, suggesting its potential role as an effective therapeutic agent.


Subject(s)
Antiviral Agents/pharmacology , Curcumin/pharmacology , Hepacivirus/drug effects , Nanoparticles/chemistry , Antiviral Agents/chemistry , Cell Line , Chitosan/chemistry , Curcumin/administration & dosage , Curcumin/chemistry , Genotype , Hepacivirus/genetics , Hepacivirus/pathogenicity , Humans , Liver Neoplasms/virology , Nanoparticles/therapeutic use , Viral Core Proteins/metabolism , Viral Nonstructural Proteins/chemistry , Viral Nonstructural Proteins/metabolism , Virus Internalization/drug effects , Virus Replication/drug effects
12.
3 Biotech ; 8(6): 282, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29881660

ABSTRACT

Several actinomycetes strains were isolated from different marine sponges collected from the Red Sea shore in Egypt. The efficiency of their crude extracts to inhibit histone deacetylase (HDAC) enzyme was investigated in the nuclear extract of Hela cell line. The crude extract corresponding to Streptomyces sp. SP9 isolated from the marine sponge Pseudoceratina arabica showed a promising HDAC inhibitory activity with 64 and 81% at 50 and 100 µg/ml, respectively. The strain was identified as Streptomyces sp. by phylogenetic analyses based on its 16S rRNA gene sequence. The major compounds of Streptomyces sp. SP9 were isolated and purified by different chromatographic methods. The chemical structure of the isolated compounds was identified on the basis of their spectroscopic data including mass, 1H and 13C NMR, and by comparison with those of authenticated samples. Structures of compounds 1 and 2 were established as heliomycin and tetracenomycin D, respectively. These compounds exhibited HDAC inhibitory activities with IC50 values of 29.8 ± 0.04 µg/ml for heliomycin (1) and 10.9 ± 0.02 µg/ml for tetracenomycin D (2). A computational docking study for compounds 1 and 2 against HDAC1, HDAC2, and HDAC3 was performed to formulate a hypothetical mechanism by which the tested compounds inhibit HDAC. Tetracenomycin D (2) showed a good binding interactions with HDAC2 (- 5.230 kcal/mol) and HDAC3 (- 6.361 kcal/mol).

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