Re: What temperature does the enzyme Pectinase denature at? see below

The pectinase from Aspergillus niger is stable below 35 degrees C. However there are many sources of pectinase, and it is likely that the pectinase isolated from other species might have different temperature tolerances.

You can find a more detailed explanation of protein denaturation on the Encyclopedia.com website (www.encyclopedia.com/html/ d1/denatura.asp). More information on pectinase can be found at: www.enzymes.co.uk/answer24_pectinase.htm.

Enzymes are proteins. Like all proteins, they are made up of a string of many amino acids that are chemically bonded together. Proteins might be just strands of molecular spaghetti, if not for the remarkable fact that they assume a very definite three-dimensional shape. This process is called protein folding. It is only in this final, folded shape that most proteins are active. When proteins become denatured, they lose this shape and become unfolded. Denatured proteins lose their characteristic biochemical activities. Enzymes, such as pectinase, are completely inactive when they become denatured.

The forces holding proteins in their three-dimensional, folded state are often not very strong. Denaturing occurs when these forces are overcome, causing the protein to lose its shape. Proteins can be denatured by heating, or by treatment with various chemicals such as acids or bases. You can see proteins denaturing with your own eyes when you cook an egg. The white of an egg is largely protein, and upon heating, this material changes from a translucent liquid to a white opaque solid. This visual change is a result of the proteins becoming denatured as a result of heat.