A biochemist discovers and purifies a new enzyme, generating the purification table below. Procedure Total protein (mg)Activity (units) 1. Crude extract 20,000 4,000,000 2. Precipitation (salt) 5,000 3,000,000 3. Precipitation (pH) 4,000 1,000,000 4. lon-exchange chromatography 200 800,000 5. Affinity chromatography 50 750,000 6. Size-exclusion chromatography 45 675,000 (a) From the information given in the table, calculate the specific activity of the enzyme after cach purification procedure. (b) Which of the purification procedures used for this enzyme is most effective? (c) Which of the purification procedures is least effective? (d) Is there any indication based on the results shown in the table that the enzyme after step 6 is now pure? (e) What else could be done to estimate the purity of the enzyme preparation?

A continuous enzyme reactor consists of a stirred tank of volume 0.01 m3 through which liquid is pumped at 0.02 m3⁄h. The enzyme is immobilised onto non-porous, spherical support particles, and the contents are stirred well to ensure that the composition is uniform and that the particles remain in suspension. A plastic mesh has been placed in front of the exit pipe to prevent the particles from leaving the vessel. The reactor is used to carried out a 98% conversion of a substrate entering at 0.1 kmol m3 ⁄ . Michaelis-Menten kinetics apply, with the following enzyme characteristics: Turnover number = 1 × 10^3 s KM = 5 × 10−3 kmol m3 ⁄ Enzyme RMM = 65,000 (a) If the enzyme is stable, calculate the mass of enzyme that needs to be immobilised. (b) If the enzyme is not stable and experiences exponential denaturation with a half-life of 10 h at the reaction temperature, determine the denaturation constant. (c) How would you expect denaturation to affect the reactor performance?

This is my data collected from a Succinate Dehyrogenase Enzyme Assay - I am asked to plot a Concentration vs Time while plotting the Resuspended and Supernatant Reaction; how can this be completed? Test Tube Concentration (uM) Absorbance @ 600nm #1 0 0.00 #2 5 0.090 #3 10 0.187 #4 20 0.368 #5 40 0.715 #6 60 1.075     Table 3. Succinate Dehydrogenase Assay @ 600 nm Time point (min): Resuspended Pellet Reaction Absorbance Supernatant Reaction Absorbance Enzyme Reaction Control Absorbance 0 43.2 44.2 46.1 3 43.3 44.8   6 43.0 44.9   9 42.6 45.2   12 43.5 45.6   15 44.0 45.7   18 43.8 45.9   21 44.0 46.4   24 44.1 46.5   27 43.9 46.7   30 43.7 46.9 43.6

is there a role for the protein data bank in biochemical research? if so, describe it.    I am so confused on what he is asking our textbook doesn't talk about that. we are using the principle of biochemistry eighth edition: David L.Nelson