The Effect of pH on the Activity of the Enzyme Amylase Essay

Good Essays
The Effect of pH on the Activity of the Enzyme Amylase

Aim :-

To find the effect of pH on the activity of the enzyme amylase.

An enzyme is a type of protein found in all living cells. Enzymes act as biological catalysts, breaking down substrates without needing a high temperature, allowing all the chemical reactions of metabolism to take place, regulating the speed at which they progress, lowering the activation energy and providing a means of controlling individual biochemical pathways.

Enzymes owe their activity to the precise three-dimensional shape of their molecules. According to the 'lock-and-key' hypothesis, the substrates upon which an enzyme fit into a special slot in the enzyme
…show more content…
The acidity of a chemical is determined by how concentrated the chemical is with Hydrogen ions.

This is describe in an example

Loses H Gains H

Alkaline solution Acidic Solution


Overall Negative charge "Zwitterion" Overall Positive charge

lost H so makes solution No change gained H so makes solution

more acidic. less acidic.

As the solution becomes more concentrated with hydrogen ions the more effective it is on taking up the R (residual) group on amino acids: Lys, Arg, His, Asp and Glu. This affects the way in which they bond with each other therefore affect their 3D arrangement. So if the ionic bonds are important to structural stability, then the shape of the enzyme will change which in turn affects the functionality of the enzyme.

As a type of protein, enzymes are easily affected by changes in pH. At their optimum pH the shape of the enzyme is such the active site can fit perfectly with the substrate. As the pH deviates, either decrease or increase from the optimum the acid or base conditions begin to disrupt some of the loops between the loops of the protein chains. If this disruption occurs on the active site the site will become distorted and the substrate will not fit perfectly. Thus not all enzymes will be able to catalyse (break down) their reaction. Further increase or
Get Access