5 In preparation for detailed mechanistic studies of a membr

5. In preparation for detailed mechanistic studies of a membrane-associated ATPase, you attempt to purify the enzyme. Table 1, below, summarizes the results of your preliminary attempts at purification. The membrane fraction suspected to contain the enzyme of interest were purified by density gradient centrifugation, solubilized with the non-denaturing, nonionic detergent Triton X-100 and subjected to gel-filtration on a column packed with the gel-filtration medium Superose 12. All of the Superose fractions containing ATP hydrolytic activity, which eluted as a single peak, were subsequently subjected to anion-exchange chromatography on a column packed with Mono-Q. Table 1- Solubilization and purification of membrane-associated ATPase. The results shown are for the purification of the ATPase from a membrane fraction purified by density gradient centrifugation. ATPase activity was measured in buffered media containing a 2 mM ATP (a saturating concentration), 2 mM MgSO4 and 100 mM KCl. A specific activity of 1 mol/mg/ corresponds to 1 mol ATP hydrolyzed to ADP Pi per min mg membrane protein per min.

Solution

The specific activity of a protein is activity of a particular protein/mg of the protein in the sample. In this case the crude fraction has an specific activity of 0.15 which means it has 0.15% of ATPase per mg of protein isolated.

Since relative abundant protein has to be 0.5%(w/w), In this case this protein is not relatively abundant since it has only 0.15/mg.

For more specific answer, the activity and the amount of protein in each step has to be provided.