can any1 pls tell me the effects of changes in physical conditions on protein structure.?

Question

please also provide good sites as to where i can research these :) thanks. i really am messed up when it comes to biochem lab questions..

Answer 1

The following is for your refresher course:
Proteins are made up of amino acids (functional group 'plus' nucleic acid) joined together by polypeptide linkages. You can easily memorize the first seven amino acids using the code GAVLIST (Glycine, Alanine, Valine, Leucine, Iso-leucine, Serine, Tryptophan). The building block can be easily memorized: R-CH(NH2)-COOH. Just replace the R group to obtain the other amino acids.
The effects of high temperatures, microorganisms, radiations, etc., break down the polypeptide linkages hence the protein is "denatured." This terminology is different from "denatured" ethyl alcohol which is the process of adulterating poisonous compounds hence rendering it non-consumable by humans. For example, when you boil an egg for more than 15 minutes the protein breaks down and the sulfur content of one of the amino acids is released. You can really smell this sulfur much more see it coating the hardened yolk. The white portion also hardens. Therefore, the protein is denatured.
When you eat this egg you will further observe the "physical" effect of this change when you fart. You better stay away from the crowd! No kidding.
If you are thinking about the structure of DNA (De-oxy Ribonucleic Acid), for example, the helical representation has nothing to do with the physical changes per your question. DNA is made up of amino acids and it is a polypeptide linkage.

Answer 2

At low temperatures, the proteins have a native structure well organized. The most common are alpha-helix or betasheet. This is called secondary structure. When you warm the solutions, The hydrogen bounds collapse and the proteins are denaturated and you obtain a coil