The effect of Lead ions on amylase activity
Aim
What is the effect of Lead ions on the enzyme Amylase. And does it have an inhibitory effect, which causes the substrate, in this case starch to be blocked from the reaction process in the enzyme catalyst. Also is the effect reversible or irreversible, which is put on the amylase.
Method
Apparatus and substances required
Test tube holder 2% starch solution
6 boiling tubes labelled 1 to 6 1% lead nitrate solution
6 test tubes labelled A to E, ( F) Dimple tiles
5 test tubes labelled A1, B2, C3, D4, E5, (F6) 5 ml syringe
1% Amylase solution 4 dropping pipettes
Stop clock
Firstly, in each of the boiling tubes place 8 ml of 2% starch solution using the syringe. Then in each of the test tubes labelled A to F add 1ml of 1% Amylase solution. In the remaining 6 test tubes add the different concentrations of the lead nitrate solution as shown below in their corresponding test tubes.
All concentrations are achieved by serial dilution originally coming from a 1% lead nitrate solution.
Overall
Concentration of Lead nitrate in solution
A1 - 1ml lead nitrate solution (1%) 1%
B2 - 0.8 ml of 1% lead nitrate solution, 0.2 ml of distilled water 0.8%
C3 - 0.6 ml of 1% lead nitrate solution, 0.4 ml of distilled water 0.6%
D4 - 0.4ml of 1% lead nitrate solution, 0.6 ml of distilled water 0.4%
E5 - 0.2 ml of 1% lead nitrate solution, 0.8 ml of distilled water 0.2%
F6 - N/A N/A
After these are all measured out accurately fill dimple tiles with iodine solution. To start the reaction mix the two test tubes, A and A1 in to boiling tube, 1mix well and start the clock, and every...