The lipases from different sources were screened for their ability to catalyze the resolution of 2-octanol in organic solvents with vinyl acetate as the acylating reagent. The medium effect has been studied on the irr...The lipases from different sources were screened for their ability to catalyze the resolution of 2-octanol in organic solvents with vinyl acetate as the acylating reagent. The medium effect has been studied on the irreversible transesterification with varying water activity(a_w). The influence of vinyl acetate concentration on it has also been investigated. Under the optimal conditions, the enantiomeric ratio(E value) of pseudomonas fluorescence lipase(PFL) exceeded 200 with an enantiomeric excess(e.e.) of S-2-octanol above 99% at a 51% degree of conversion.展开更多
The antigenic variation of influenza A virus hemagglutinin (HA) glycoproteins requires frequent changes in vaccine formulation. The new strategy of creating influenza seed strains for vaccine production is to generate...The antigenic variation of influenza A virus hemagglutinin (HA) glycoproteins requires frequent changes in vaccine formulation. The new strategy of creating influenza seed strains for vaccine production is to generate 7 + 1 reassortants that contain seven genes from a high-yield virus A/Puerto Rico/8/34[A/PR/8/34](H1N1) and the HA gene from the circulating strains. By using this DNA-based cotransfection technique, we generated 7 + 1 reassortants rgH3N1 which had the antigenic determinants of influenza virus A/Songbird/HongKong/102/00[SB/HK/01](H3N8) and 7 other genes from A/PR/ 8/34. The hemagglutinin of A/Songbird/HongKong/102/00 is 96.3% homologous to that of A/Equine/Jilin/98[Eq/Jl/89] (H3N8). The resulting virus rgH3N1 grows to high HA titers in chicken embryonated eggs, allowing vaccine preparation in unconcentrated allantoic fluid. The rgH3N1 is stable after multiple passages in embryonated eggs. The reassortant rgH3N1 virus could be used as vaccine candidate to reduce the reemergence of equine influenza outbreaks.展开更多
基金Supported by the National Natural Science Foundation of China(No.2 0 0 72 0 11and2 0 2 72 0 17)
文摘The lipases from different sources were screened for their ability to catalyze the resolution of 2-octanol in organic solvents with vinyl acetate as the acylating reagent. The medium effect has been studied on the irreversible transesterification with varying water activity(a_w). The influence of vinyl acetate concentration on it has also been investigated. Under the optimal conditions, the enantiomeric ratio(E value) of pseudomonas fluorescence lipase(PFL) exceeded 200 with an enantiomeric excess(e.e.) of S-2-octanol above 99% at a 51% degree of conversion.
文摘The antigenic variation of influenza A virus hemagglutinin (HA) glycoproteins requires frequent changes in vaccine formulation. The new strategy of creating influenza seed strains for vaccine production is to generate 7 + 1 reassortants that contain seven genes from a high-yield virus A/Puerto Rico/8/34[A/PR/8/34](H1N1) and the HA gene from the circulating strains. By using this DNA-based cotransfection technique, we generated 7 + 1 reassortants rgH3N1 which had the antigenic determinants of influenza virus A/Songbird/HongKong/102/00[SB/HK/01](H3N8) and 7 other genes from A/PR/ 8/34. The hemagglutinin of A/Songbird/HongKong/102/00 is 96.3% homologous to that of A/Equine/Jilin/98[Eq/Jl/89] (H3N8). The resulting virus rgH3N1 grows to high HA titers in chicken embryonated eggs, allowing vaccine preparation in unconcentrated allantoic fluid. The rgH3N1 is stable after multiple passages in embryonated eggs. The reassortant rgH3N1 virus could be used as vaccine candidate to reduce the reemergence of equine influenza outbreaks.
