[jena]

Hi,

My Question:

If an enzyme present in the human body is isolated and its activity is tested invitro, plot a graph of its relative activity vs temp(25,37, 50ºC).

I don't understand, what is its relative activity supposed to be ???How do you even calculate relative activity?

Please help and Thank You

[jena]

Hi

I think I figured out what I'm supposed to do. Am I supposed to graph the enzyme activity according to what temperature it works best at. For example 37 degrees, would be the best temperature for the enzyme to function at thus, I could graph it as having 100% relative activity.

Is this correct???

Thank You

[Yggdrasil]

Yes.  Temperature affects two factors.  First increasing the temperature of a reaction will increase its rate.  However, increasing temperature will also decrease the stability of the enzyme.  Therefore, at low temperatures, the molecules don't have enough energy to react quickly and at high temperatures, the enzyme is denatured (it unfolds and cannot catalyze the reaction).  Therefore, most enzymes have an optimum temperature at which they have maximum activity.

[ahpeasant]

relative activity is also often found in the report on the immobilization of enzyme:

The activity yield residue after coupling was defined as activity yield (%) = C/A × 100, and the coupled yield (%) = (A ? B)/A × 100, where A is the total activity of enzyme added in the initial immobilization solution; B is the activity of the same amount of enzyme in supernatant after the immobilization; and C is the activity of the immobilized papain. The relative activity (%) was defined as C/ (A ? B) ×100.