The definition of the Isoelectric point (pI) of a protein.

What is the definition of the "isoelectric point" (pI) of a protein?

The calculation of the isoelectric point (pI) of an amino acid. General method, step by step solutions to the problems, and definitions of concepts/terms provided.

Calculate the isoelectric point (pI) of each of the following amino acids (a) glycine (b) glutamic acid (c) arginine

Understanding and using the Henri-Michaelis-Menten equation.

For an enzyme which obeys Henri-Michaelis-Menten kinetics, (1) At what substrate concentration will an enzyme characterized by a kcat of 30 s-1 and Km of 0.005 M show one quarter of its maximal rate? (2) Calculate the fraction of Vmax that would be found when [S]=0.5 Km, [S]=3Km, and [S]=10Km

Understanding under what conditions an enzyme achieves maximal velocity (Vmax) and the turnover number of an enzyme.

The enzyme carbonic anhydrase is found in erythrocytes, and has a molecular mass of approximately 30000 Da. The hydration reaction catalyzed by this enzyme is reversible, and plays a role in the transport of CO2 from the tissues to the lungs. H2O + CO2 <-> H2CO3 If 20 micrograms of pure enzyme catalyzes the hydration of 0.50 g of Co2 in 1 minute, at 37 degrees Celsius, under optimal conditions, what is the turnover number (kcat) for carbonic anhydrase?

Enzyme Kinetics: Understanding the Henri-Michaelis-Menten equation/model.

An enzyme with a Km of 0.36 mM was assayed using substrate concentrations of 3 x 10E-7 M, 9.5 x 10E-5 M, 1.5 x 10E-4, 1.16x10E-3, 3 x 10E-3 M, 0.01 M, 0.08 M. At a substrate concentration of 0.08 M, the initial velocity was 192 nM/min. Calculate the initial velocity at each of the other substrate concentrations. Graph the calculated velocities using the Henri-Michaelis-Menten model.