Repurposing benzimidazole and benzothiazole derivatives as potential inhibitors of SARS-CoV-2 : DFT, QSAR, molecular docking, molecular dynamics simulation, and in-silico pharmacokinetic and toxicity studies

Density Functional Theory (DFT) and Quantitative Structure-Activity Relationship (QSAR) studies were performed on four benzimidazoles (compounds 1–4) and two benzothiazoles (compounds 5 and 6), previously synthesized by our group. The compounds were also investigated for their binding affinity and interactions with the SARS-CoV-2 Mpro (PDB ID: 6LU7) and the human angiotensin-converting enzyme 2 (ACE2) receptor (PDB ID: 6 M18) using a molecular docking approach. Compounds 1, 2, and 3 were found to bind with equal affinity to both targets. Compound 1 showed the highest predictive docking scores, and was further subjected to molecular dynamics (MD) simulation to explain protein stability, ligand properties, and protein–ligand interactions. All compounds were assessed for their structural, physico-chemical, pharmacokinetic, and toxicological properties. Our results suggest that the investigated compounds are potential new drug leads to target SARS-CoV-2

In the face of the future, what do we learn from COVID-19?

Coronavirus disease (COVID-19) is a highly contagious infection caused by a recently identified coronavirus. The first known case was discovered in December 2019 in Wuhan, China. Since then, the illness has spread globally, resulting in an ongoing epidemic. Here, we would like to address one of the most pressing and outstanding questions which rise about COVID-19 during the year and a half since its discovery: what have we learned from COVID-19

Exploring particulate methane monooxygenase (pMMO) proteins using experimentation and computational molecular docking

Researchers had difficulty studying pure full-length pMMO due to the solubility problem and loss of enzymatic activity after its elimination from the native membrane. To study pMMO, we performed several bioinformatics tools to analyze the entire structure of it available in the PDB database. We also carried out molecular docking studies to prove that quinone and duroquinone can bind to several sites of eight pMMO proteins. However, some sites in the orientation are not required by the catalysis process. Furthermore, molecular docking was done for predicting the binding affinity of P450 with target enzymes. Interestingly, our analysis illustrated that pMMO can produce methanol in the presence of quinone and duroquinone and the absence of Cu. Moreover, pmoB1 can interact with P450. Consequently, our findings highlight, for the first time, the significance of studying the membrane of pMMO to provide valuable insights into its functions

Molecular dynamic and bioinformatic studies of metformin-induced ACE2 phosphorylation in the presence of different SARS-CoV-2 S protein mutations

The SARS-CoV-2 infection activates host kinases and causes high phosphorylation in both the host and the virus. There were around 70 phosphorylation sites found in SARS-CoV-2 viral proteins. Besides, almost 15,000 host phosphorylation sites were found in SARS-CoV-2-infected cells. COVID-19 is thought to enter cells via the well-known receptor Angiotensin-Converting Enzyme 2 (ACE2) and the serine protease TMPRSS2. Substantially, the COVID-19 infection doesn’t induce phosphorylation of the ACE2 receptor at Serin-680(s680). Metformin's numerous pleiotropic properties and extensive use in medicine including COVID-19, have inspired experts to call it the “aspirin of the twenty-first century”. Metformin's impact on COVID-19 has been verified in clinical investigations via ACE2 receptor phosphorylation at s680. In the infection of COVID-19, sodium-dependent transporters including the major neutral amino acid (B0AT1) is regulated by ACE2. The structure of B0AT1 complexing with the COVID-19 receptor ACE2 enabled significant progress in the creation of mRNA vaccines. We aimed to study the impact of the interaction of the phosphorylation form of ACE2-s680 with wild-type (WT) and different mutations of SARS-CoV-2 infection such as delta, omicron, and gamma (γ) on their entrance of host cells as well as the regulation of B0AT1by the SARS-CoV-2 receptor ACE2. Interestingly, compared to WT SARS-CoV-2, ACE2 receptor phosphorylation at s680 produces conformational alterations in all types of SARS-CoV-2. Furthermore, our results showed for the first time that this phosphorylation significantly influences ACE2 sites K625, K676, and R678, which are key mediators for ACE2-B0AT1 complex

Dual synergistic inhibition of COX and LOX by potential chemicals from Indian daily spices investigated through detailed computational studies

Abstract Cyclooxygenase (COX) and Lipoxygenase (LOX) are essential enzymes for arachidonic acid (AA) to eicosanoids conversion. These AA-derived eicosanoids are essential for initiating immunological responses, causing inflammation, and resolving inflammation. Dual COX/5-LOX inhibitors are believed to be promising novel anti-inflammatory agents. They inhibit the synthesis of prostaglandins (PGs) and leukotrienes (LTs), but have no effect on lipoxin formation. This mechanism of combined inhibition circumvents certain limitations for selective COX-2 inhibitors and spares the gastrointestinal mucosa. Natural products, i.e. spice chemicals and herbs, offer an excellent opportunity for drug discovery. They have proven anti-inflammatory properties. However, the potential of a molecule to be a lead/ drug candidate can be much more enhanced if it has the property of inhibition in a dual mechanism. Synergistic activity is always a better option than the molecule's normal biological activity. Herein, we have explored the dual COX/5-LOX inhibition property of the three major potent phytoconsituents (curcumin, capsaicin, and gingerol) from Indian spices using in silico tools and biophysical techniques in a quest to identify their probable inhibitory role as anti-inflammatory agents. Results revealed the dual COX/5-LOX inhibitory potential of curcumin. Gingerol and capsaicin also revealed favorable results as dual COX/5-LOX inhibitors. Our results are substantiated by target similarity studies, molecular docking, molecular dynamics, energy calculations, DFT, and QSAR studies. In experimental inhibitory (in vitro) studies, curcumin exhibited the best dual inhibitory activities against COX-1/2 and 5-LOX enzymes. Capsaicin and gingerol also showed inhibitory potential against both COX and LOX enzymes. In view of the anti-inflammatory potential these spice chemicals, this research could pave the way for more scientific exploration in this area for drug discovery