The angiotensin-converting enzyme (ACE)-related carboxypeptidase, ACE-II, is a type I integral membrane protein of 805 amino acids that contains one HEXXH-E zinc binding consensus sequence. ACE-II has been implicated in the regulation of heart function and also as a functional receptor for the coronavirus that causes the severe acute respiratory syndrome (SARS). In this study, the potential of some flavonoids present in propolis to bind to ACE II receptors was calculated in silico.Binding constants of ten flavonoids, caffeic acid, caffeic acid phenethyl ester, chrysin, galangin, myricetin, rutin, hesperetin, pinocembrin, luteolin and quercetin were measured using the AutoDock 4.2 molecular docking program. And also, these binding constants were compared to reference ligand of MLN-4760.The results are shown that rutin has the best inhibition potentials among the studied molecules with high binding energy -8,97 kcal/mol and Ki 0,261 M, and it is followed by myricetin, caffeic acid phenethyl ester, hesperetin and pinocembrin. However, the reference molecule has binding energy of -7,28 kcal/mol and 4,65 M. In conclusion, the high potential of flavonoids in ethanolic propolis extracts to bind to ACE II receptors indicates that this natural bee product has high potential for Covid-19 treatment, but this needs to be supported by experimental studies.

No abstract

The recent outbreak of coronavirus disease (COVID‐19) in China caused by the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has led to worldwide human infections and deaths. The nucleocapsid (N) protein of coronaviruses (CoVs) is a multifunctional RNA binding protein necessary for viral RNA replication and transcription. Therefore, it is a potential antiviral drug target, serving multiple critical functions during the viral life cycle. This study addresses the potential to repurpose antiviral compounds approved or in development for treating human CoV induced infections against SARS‐CoV‐2 N. For this purpose, we used the docking methodology to better understand the inhibitory mechanism of this protein with the existing 34 antiviral compounds. The results of this analysis indicate that rapamycin, saracatinib, camostat, trametinib, and nafamostat were the top hit compounds with binding energy (−11.87, −10.40, −9.85, −9.45, −9.35 kcal/mol, respectively). This analysis also showed that the most common residues that interact with the compounds are Phe66 , Arg68 , Gly69 , Tyr123 , Ile131 , Trp132 , Val133 , and Ala134 . Subsequently, protein‐ligand complex stability was examined with molecular dynamics simulations for these five compounds, which showed the best binding affinity. According to the results of this study, the interaction between these compounds and crucial residues of the target protein were maintained. These results suggest that these residues are potential drug targeting sites for the SARS‐CoV‐2 N protein. This study information will contribute to the development of novel compounds for further in vitro and in vivo studies of SARS‐CoV‐2, as well as possible new drug repurposing strategies to treat COVID‐19 disease.

No abstract

No abstract