RESUMEN
We firstly disclose single compound yields better therapeutic outcome than Remdesivir in COVID-19 hamster treatments as it is armed with direct inhibition viral replication and intrinsic suppression inflammatory cytokines expression. Crystal data reveals that Au (I), released from Au22Glutathione18 (GA), covalently binds thiolate of Cys145 of SARS-CoV-2 Mpro. GA directly decreases SARS-CoV-2 viral replication (EC50: ~0.24 M) and intrinsically down-regulates NF{kappa}B pathway therefore significantly inhibiting expression of inflammatory cytokines in cells. The lung viral load and inflammatory cytokines in GA-treated COVID-19 transgenic mice are found to be significantly lower than that of control mice. When COVID-19 golden hamsters are treated by GA, the lung inflammatory cytokines levels are significantly lower than that of Remdesivir while their lung viral load are decreased to same level. The pathological results show that GA treatment significantly reduce lung inflammatory injuries when compared to that of Remdesivir-treated COVID-19 golden hamsters. One Sentence SummaryWe found that gold cluster molecule directly inhibits SARS-CoV-2 replication and intrinsically suppresses inflammatory cytokines expression in COVID-19 transgenic mouse and golden hamster model, gold cluster providing a better lung injury protection than Remdesivir in COVID-19 golden hamsters via intranasally dropping administration.
RESUMEN
Smu_195c is a protein with 86 amino acids in Streptococcus mutans, a primary pathogen for human dental caries. The specific function of Smu_195c is still unknown and there are no conserved domains in it. In order to find out its function, the gene encodes Smu_195c was cloned and expressed in E. coli as N-terminally 6*His tagged recombinant protein. Two crystal forms were obtained by the hanging drop method. Form Ⅰ belongs to space group P6122 or P6522 with the unit cell parameters a = b = 62.93 (A), c= 90.63 (A), γ=120° and form Ⅱ belongs to the space group P41212 or P43212 with the unit cell parameters a =b=57.97 (A), c = 103.51 (A).Crystals from the protein with His-tag belong to form Ⅰ, however, crystals from the protein without His-tag belong to both.
RESUMEN
Deoxycytidylate (dCMP) deaminase is an enzyme belonged to dCMP cyt deam family. The dCMP deaminase from Streptococcus mutans UA159 was cloned and expressed in E. coli, and purified to homogeneity. The FPLC size exclusion chromatography analysis reveals that the S. mutans dCMP deaminase forms hexamer in solution. The protein was crystallized using hanging drop vapour-diffusion method and diffracted to a resolution of 3.1 ?. The diffraction data were collected at BSRF beamline 3W1A. The crystals belong to P213 space group, with unit cell parameters a = b = c = 113.2 ?, ? = ? = ? = 90?. Assuming there are two subunits per asymmetric unit, the Matthews coefficient is 3.6 ?3?Da-1. This is the first crystallization report of the wild-type deoxycytidylate deaminase.
RESUMEN
Deoxycytidylate (dCMP) deaminase is an enzyme belonged to dCMP cyt deam family. The dCMP deaminase from Streptococcus mutans UA159 was cloned and expressed in E. coli, and purified to homogeneity. The FPLC size exclusion chromatography analysis reveals that the S. mutans dCMP deaminase forms hexamer in solution. The protein was crystallized using hanging drop vapour-diffusion method and diffracted to a resolution of 3.1 (A). The diffraction data were collected at BSRF beamline3W1A. The crystals belong to P213 space group, with unit cell parameters a = b = c = 113.2(A), α =β = γ = 90°. Assuming there are two subunits per asymmetric unit, the Matthews coefficient is 3.6 (A)3 ·Da-1. This is the first crystallization report of the wild-type deoxycytidylate deaminase.