Question

Q1)a)

Research Caspase-2 protease:

Indicate i) the class of enzymes to which Caspase-2 belongs, ii) the kind of bond that is modified by this enzyme, iii) indicate the substrate that is recognised by the enzyme using the amino acid three letter code and iv) whether the enzyme displays high or low substrate specificity.

b) You are measuring enzyme activity in the presence and absence of a compound that is a competitive inhibitor. What would happen to i) the measured K_m and ii) the measured V_max if the concentration of a competitive inhibitor were doubled? (Justify your answers in a single sentence by described how the inhibitor affects the enzyme using language described in the unit)

c) A final step in the analysis of enzymatic activity during practicals 3 and 4 was the addition of NaOH to your samples. Provide two reasons why you added NaOH and explain the molecular effects that NaOH has in each case!

Answer 1

Please find the answers below:

Answer 1:

Part i: Technically, the caspase-2 is a cystein protease by nature which means that it cuts the target protein by identifying specific localization of the cystein residue in it.

Part ii: The caspase 2 is known to modify the formation and localization of hydrogen bonds in the target.

Part iii: The substrate recognized by caspase 2 is a tri-peptide sequence in the sample i.e. valine, aspartic acid and glutamine or VDQ sequence.

Part iv: Owing to its specific cleavage site present in its death domain, the enzyme is very specific to the kind of substrate it digests.