Search

Background: Plants of the Amaryllidaceae family have been under intense scrutiny for the presence of a couple of alkaloidal secondary metabolites with endued cytotoxic activity, such as pancratistatin (1), 7-deoxypancratistatin (2), narciclasine (3), 7-deoxynarciclasine (4), trans-dihydronarciclasine (5), and 7-deoxy-trans-dihydronarciclasine (6). Nevertheless, preclinical evaluation of these alkaloids has been put on hold because of the limited quantity of materials available from isolation. Aim: To explore the underlying cytotoxic molecular mechanisms of the Amaryllidaceae alkaloids (1-6) and to assess their absorption, distribution, metabolism, excretion, and toxicity (ADMET) profiles using chemoinformatic tools. Materials And Methods: AutoDock 4.0 software along with different in silico chemoinformatic tools, namely PharmMapper, Molinspiration, MetaPrint2D, and admetSAR servers, were used to assess the drugability of the Amaryllidaceae alkaloids (1-6). Results: Deoxycytidine kinase (dCK) (PDB: 1P60) was predicted as a potential target with fitting score of 5.574. In silico molecular docking of (1-6) into dCK revealed good interactions, where interesting hydrogen bonds were observed with the amino acid residues-Gly-28 and Ser-35-located in the highly conserved P-loop motif. This motif plays a special role in dCK function. Contrary to (1), in silico pharmacokinetic results have shown good absorption and permeation and thus good oral bioavailability for (2-6). Conclusion: The in silico docking data have proposed that the reported cytotoxic activity of the Amaryllidaceae alkaloids (1-6) could be mediated through dCK inhibition. In addition, the ADMET profile of these alkaloids is promising and thus (1-6) could be candidates for future drug development. [ABSTRACT FROM AUTHOR]

Background: Mycetoma is a distinct body tissue destructive and neglected tropical disease. It is endemic in many tropical and subtropical countries. Mycetoma is caused by bacterial infections (actinomycetoma) such as Streptomyces somaliensis and Nocardiae or true fungi (eumycetoma) such as Madurella mycetomatis. To date, treatments fail to cure the infection and the available marketed drugs are expensive and toxic upon prolonged usage. Moreover, no vaccine was prepared yet against mycetoma. Aim: The aim of this study is to predict effective epitope-based vaccine against fructose-bisphosphate aldolase enzymes of M. mycetomatis using immunoinformatics approaches. Methods and materials: Fructose-bisphosphate aldolase of M. mycetomatis sequence was retrieved from NCBI. Different prediction tools were used to analyze the nominee's epitopes in Immune Epitope Database for B-cell, T-cell MHC class II and class I. Then the proposed peptides were docked using Autodock 4.0 software program. Results and conclusions: The proposed and promising peptides KYLQ show a potent binding affinity to B-cell, FEYARKHAF with a very strong binding affinity to MHC I alleles and FFKEHGVPL that shows a very strong binding affinity to MHC II and MHC I alleles. This indicates a strong potential to formulate a new vaccine, especially with the peptide FFKEHGVPL which is likely to be the first proposed epitope-based vaccine against fructose-bisphosphate aldolase of M. mycetomatis. This study recommends an in vivo assessment for the most promising peptides especially FFKEHGVPL. [ABSTRACT FROM AUTHOR]

Mycetoma is a distinct flesh eating and destructive neglected tropical disease. It is endemic inmany tropical and subtropical countries. Mycetoma caused by bacterial infections (actinomycetoma) such asStreptomycessomaliensis and Nocardiae or true fungi (eumycetoma) such as M.mycetomatis. To date, treatments fail to cure the infection and the available marketed drugs are expensive and toxic uponprolonged usage. Moreover, no vaccine was prepared yet against mycetoma. The aim of this study is to predict effective epitope-based vaccine against fructose-bisphosphate aldolaseenzymes of M. mycetomatis using immunoinformatic approaches. Materials and Methods: Fructose-bisphosphate aldolase of M.mycetomatis Sequence was retrieved fromNCBI. Different prediction tools were used to analyze the nominee's epitopes in Immune Epitope Databasefor B-cell, T-cell MHC class II & I. Then the proposed peptides were docked using Autodock 4.0 softwareprogram. Results and Conclusions: The proposed and promising peptides KYLQ show a potent bindingaffinity to Bcell,FEYARKHAF with a very strong binding affinity to MHC1 alleles and FFKEHGVPL thatshow a verystrong binding affinity to MHC11and MHC1 alleles. This indicates a strong potential toformulate a newvaccine, especially with the peptide FFKEHGVPL that is likely to be the first proposed epitope-basedvaccine against Fructose-bisphosphate aldolase of M.mycetomatis. This study recommends an in-vivoassessment for the most promising peptides especially FFKEHGVPL. [ABSTRACT FROM AUTHOR]

Multidisciplinary research efforts on potential COVID-19 vaccine and therapeutic candidates have increased since the pandemic outbreak of SARS-CoV-2 in 2019. This search has become imperative due to the increasing emergences and limited widely available medicines. The presence of bioactive anti-SARS-CoV-2 molecules was examined from various plant sources. Among them is a group of proteins called lectins that can bind carbohydrate moieties. In this article, we present ten novel, chitin-specific Hevein-like lectins that were derived from Selaginella moellendorffii v1.0's genome. The capacity of these lectin homologs to bind with the spike protein of SARS-CoV-2 was examined. Using the HDOCK server, 3D-modeled Hevein-domains were docked to the spike protein's receptor binding domain (RBD). The Smo446851, Smo125663, and Smo99732 interacted with Asn343-located complex N -glycan and RBD residues, respectively, with binding free energies of -17.5, -13.0, and -26.5 Kcal/mol. The molecular dynamics simulation using Desmond and the normal-state analyses via torsional coordinate association for the Smo99732-RBD complex using iMODS is characterized by overall higher stability and minimum deformity than the other lectin complexes. The three lectins interacting with carbohydrates were docked against five individual mutations that frequently occur in major SARS-CoV-2 variants. These were in the spike protein's receptor-binding motif (RBM), while Smo125663 and Smo99732 only interacted with the spike glycoprotein in a protein-protein manner. The precursors for the Hevein-like homologs underwent additional characterization, and their expressional profile in different tissues was studied. These in silico findings offered potential lectin candidates targeting key N -glycan sites crucial to the virus's virulence and infection.