General Administration of Quality Supervision,Inspection and Quarantine of P.R.China has approved the following 8 national measuring verification regulations in 2010 and publicize now.
General Administration of Quality Supervision,Inspection and Quarantine of P.R.China has approved the following 11 national measuring verification regulations in 2008 and publicize now.
General Administration of Quality Supervision,Inspection and Quarantine of P.R.China hasapproved the following 24 national measuring verification regulations in 2008 and publicize now.
General Administration of Quality Supervision,Inspection and Quarantine of P.R.China has approved the following 10 national measuring verification regulations in 2008 and publicize now.
Objective: To investigate the reliability for fast estimation of Michaelis-Menten constant (Km) with calibrated specific activity at only two medium concentrations of substrate by both simulation and experimentation w...Objective: To investigate the reliability for fast estimation of Michaelis-Menten constant (Km) with calibrated specific activity at only two medium concentrations of substrate by both simulation and experimentation with arylesterase (ArE)as model. Methods: Initial rates were simulated by randomly inserting uniform absolute error, and the experimental initial rates of ArE were determined by measuring the increaser of product absorbance. Calibrated specific activities at two substrate concentrations were obtained by regression analysis, and Km was calculated according to Michaelis-Menten equation. Results: By simulation with calibrated specific activities at two medium substrate concentrations, Km could be calculated according to Michaelis-Menten equation with reasonable precision and accuracy. By experimentation with substrates of 2-naphthyl acetate, phenyl acetate, and p-nitrophenyl acetate, there were no differences between the mean and SD of Km of ArE for either substrate by this linear kinetic method and the Lineweaver-Burk plot. Conclusion: This linear kinetic method was reliable for fast estimation of the Km of some specified enzyme on its substrate of lower solubility or lower sensitivity for quantification by common methods.展开更多
文摘General Administration of Quality Supervision,Inspection and Quarantine of P.R.China has approved the following 8 national measuring verification regulations in 2010 and publicize now.
文摘General Administration of Quality Supervision,Inspection and Quarantine of P.R.China has approved the following 11 national measuring verification regulations in 2008 and publicize now.
文摘General Administration of Quality Supervision,Inspection and Quarantine of P.R.China hasapproved the following 24 national measuring verification regulations in 2008 and publicize now.
文摘General Administration of Quality Supervision,Inspection and Quarantine of P.R.China has approved the following 10 national measuring verification regulations in 2008 and publicize now.
文摘Objective: To investigate the reliability for fast estimation of Michaelis-Menten constant (Km) with calibrated specific activity at only two medium concentrations of substrate by both simulation and experimentation with arylesterase (ArE)as model. Methods: Initial rates were simulated by randomly inserting uniform absolute error, and the experimental initial rates of ArE were determined by measuring the increaser of product absorbance. Calibrated specific activities at two substrate concentrations were obtained by regression analysis, and Km was calculated according to Michaelis-Menten equation. Results: By simulation with calibrated specific activities at two medium substrate concentrations, Km could be calculated according to Michaelis-Menten equation with reasonable precision and accuracy. By experimentation with substrates of 2-naphthyl acetate, phenyl acetate, and p-nitrophenyl acetate, there were no differences between the mean and SD of Km of ArE for either substrate by this linear kinetic method and the Lineweaver-Burk plot. Conclusion: This linear kinetic method was reliable for fast estimation of the Km of some specified enzyme on its substrate of lower solubility or lower sensitivity for quantification by common methods.