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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, RESULTS. Meshes: Animals, Anti-Bacterial Agents, Bacterial Toxins, Flavonoids, Hemolysin Proteins, Hemolysis, Humans, Lung, Mice, Pneumonia, Staphylococcal, Staphylococcus aureus, Virulence.
user
Does morin hydrate attenuate Staphylococcus aureus virulence by inhibiting the self-assembly of α-hemolysin? Context: To investigate the mechanism by which morin hydrate inhibits the haemolytic activity of α-hemolysin (Hla), a channel-forming toxin that is important for the pathogenesis of disease in experimental animals, and its therapeutic effect against Staphylococcus aureus pneumonia in a mouse model. The results from the in vitro (haemolysis, western blot and cytotoxicity assays) and in vivo (mouse model of intranasal lung infection) experiments indicated that morin hydrate, a natural compound with little anti-Staph. aureus activity, could effectively antagonize the cytolytic activity of Hla, alleviate human lung cell injury, and protect against mortality of Staph. aureus pneumonia in a mouse model of infection. Molecular dynamics simulations, free energy calculations and mutagenesis assays were further employed to determine the catalytic mechanism of inhibition, which indicated that a direct binding of morin to the 'Stem' domain of Hla (residues I107 and T109) and the concomitant change in conformation led to the inhibition of the self-assembly of the heptameric transmembrane pore, thus inhibiting the biological activity of Hla for cell lysis.
assistant
Morin inhibited Staph. aureus virulence via inhibiting the haemolytic activity of α-hemolysin. Final Decision: yes