An electrochemical assay was developed for β-D-galactosidase in coliform bacteria Escherichia coli (E. coli) using p-aminophenyl-β-D-galactopyranoside (PAPG) as substrate. The hydrolysis of PAPG by pure β-D-galact...An electrochemical assay was developed for β-D-galactosidase in coliform bacteria Escherichia coli (E. coli) using p-aminophenyl-β-D-galactopyranoside (PAPG) as substrate. The hydrolysis of PAPG by pure β-D-galactosidase was investigated based on the cyclic voltammetric (CV) behavior of p-aminophenyl (PAP). The results obtained using the pure enzyme showed that the addition of magnesium ion facilitated the enzyme-catalytic reaction. K m at the optimal magnesium ion concentration (5 mmol/L) was 0.90 mmol/L. The substrate was also used for coliformbacteria, where β-D-galactosidase in the bacteria cells was strongly induced by isopropyl-β-D-thiogalactopyranoside (IPTG). When the E. coli cell density exceeded 1.1×10 3 mL -1, the CV response was linearly related to the number of E. coli, the detection time was about one hour. This method can be developed into a portable biosensor for rapid assay of coliform bacteria.展开更多
Several features of adenoviruses make them anattractive option as a vehicle to transfer genes intoprimary malignant neoplasms in vivo. These viruseshave low pathogenicity in humans and are notneurotoxic. In addition, ...Several features of adenoviruses make them anattractive option as a vehicle to transfer genes intoprimary malignant neoplasms in vivo. These viruseshave low pathogenicity in humans and are notneurotoxic. In addition, high titers of the virus can beachieved to allow higher levels of gene transfectionefficiency than the other vector systems. In vivotumorigenicity of G422 glioblastoma cells transfectedwith IL-2 and/or IL-3 genes decreased significantly inour privious report. In this study, recombinantadenoviruses were used to evaluate the therapeuticpotential of combined IL-2/IL-3 gene therapy in thetreatment of established subcutaneous tumor model ofG422 glioblastoma. Murine IL-2, IL-3 recombinantadenoviruses (2×10~8 pfu) were injected directly展开更多
When the cellulase hydrolyses carboxymethyl-cellulose-Na(CMC-Na), it is not fit to formula, V=KE, between reaction velocity and concentration of enzyme. Therefore, a factor that inhibits this enzyme reaction, which is...When the cellulase hydrolyses carboxymethyl-cellulose-Na(CMC-Na), it is not fit to formula, V=KE, between reaction velocity and concentration of enzyme. Therefore, a factor that inhibits this enzyme reaction, which is called the cellulase endo-inhibitor, was discovered in the fermentative medium of Trichoderma spp. It was shown as a single band through electrophoresis, indicating it is homogeneous and the inhibitor展开更多
文摘An electrochemical assay was developed for β-D-galactosidase in coliform bacteria Escherichia coli (E. coli) using p-aminophenyl-β-D-galactopyranoside (PAPG) as substrate. The hydrolysis of PAPG by pure β-D-galactosidase was investigated based on the cyclic voltammetric (CV) behavior of p-aminophenyl (PAP). The results obtained using the pure enzyme showed that the addition of magnesium ion facilitated the enzyme-catalytic reaction. K m at the optimal magnesium ion concentration (5 mmol/L) was 0.90 mmol/L. The substrate was also used for coliformbacteria, where β-D-galactosidase in the bacteria cells was strongly induced by isopropyl-β-D-thiogalactopyranoside (IPTG). When the E. coli cell density exceeded 1.1×10 3 mL -1, the CV response was linearly related to the number of E. coli, the detection time was about one hour. This method can be developed into a portable biosensor for rapid assay of coliform bacteria.
文摘Several features of adenoviruses make them anattractive option as a vehicle to transfer genes intoprimary malignant neoplasms in vivo. These viruseshave low pathogenicity in humans and are notneurotoxic. In addition, high titers of the virus can beachieved to allow higher levels of gene transfectionefficiency than the other vector systems. In vivotumorigenicity of G422 glioblastoma cells transfectedwith IL-2 and/or IL-3 genes decreased significantly inour privious report. In this study, recombinantadenoviruses were used to evaluate the therapeuticpotential of combined IL-2/IL-3 gene therapy in thetreatment of established subcutaneous tumor model ofG422 glioblastoma. Murine IL-2, IL-3 recombinantadenoviruses (2×10~8 pfu) were injected directly
文摘When the cellulase hydrolyses carboxymethyl-cellulose-Na(CMC-Na), it is not fit to formula, V=KE, between reaction velocity and concentration of enzyme. Therefore, a factor that inhibits this enzyme reaction, which is called the cellulase endo-inhibitor, was discovered in the fermentative medium of Trichoderma spp. It was shown as a single band through electrophoresis, indicating it is homogeneous and the inhibitor
