A student assays a newly purchased enzyme by the standard procedure. He dissolves 50mg of the enzyme in 100 mL water and uses 10mL for the assay. He adds the enzyme to the substrate and collects absorbance data at specified intervals. Calculate the specific activity of the enzyme if at 5 minutes absorbance was 0.345 and at 10 min absorbance was 0.645. Standard curve equation was given as Y= 0.238x.

A student performed an invertase activity assay on samples from a purification.  All reactions occurred in a reaction volume of 100 µL and lasted 3.1 minutes.  For each reaction, 5.00 µL enzyme was mixed with 50.0 mM sucrose in 10.0 mM acetate pH 4.8.  Then 400 µL of DNS was added, the samples were heated to 90 °C for 5 minutes, and 500 µL of 50.0 mM acetate pH 4.8 was added before loading a 96 well plate in triplicate.  Samples were measured at 540 nm using a path length of 0.680 cm.  The fraction with the highest activity had A540 of 0.904.  The standard of 14.00 mM hydrolyzed sucrose had A540 of 1.047 (the concentration given is of the 100 µL sample).  The no-enzyme control had A540 of 0.174.  Calculate the activity of the fraction (in nmol min-1).

A biochemist discovers and purifies a new enzyme, generating the purification table below. Procedure                          Total Protein (Mg)                           Activity (Units) Crude Extract                    20,000                                                4,000,000 Precipitation (Salt)                           5,000                                                  3,000,000 Precipitation (pH)                            4,000                                                  1,000,000 Ion Exchange Chromatography    200                                      800,000 Affinity Chromatography               50                                         750,000 Size-exclusion Chromatography   45                                         675,000 a) From the information given in the table, calculate the specific activity of the enzymeafter each purification procedure.b) Which of the purification procedures used for this enzyme is most effective (i.e., givesthe greatest relative…

You are performing an enzyme reaction that works the same way as your wheat germ acid phosphatase (WGAP) assay. First, you dissolve 10.0 umol of product into 1.00 ml of buffer, and measure an absorbance of 0.500.  Your cuvette has a 1.00 cm pathlength. Next, you perform the enzyme assay.  Your enzyme solution has a concentration of 20.0 ug/ml.      1) Mix 0.250 ml substrate buffer with 0.250 ml enzyme       2) Incubate 20.0 min      3) Stop the assay with 0.500 ml NaOH      4) Read an absorbance of 0.200    *The units required for each answer in this problem are given.  Answers to all three parts should be rounded to a maximum of three decimal places. Do not enter any letters. What is the extinction coefficient (ml/umol/cm) of the product? What is the catalytic activity (umol/min) measured in your assay? What is the specific activity (umol/min/ug) measured in your assay?