Because proteins are amphiphilic and can act as surfactants in a similiar way detergents do. They can adsorb at air-water interface and lower the surface tension of the solution which allows formation of the foam. This process might lead to protein denaturation, so when handling protein solution you should avoid foaming.
Dawid
Because proteins are amphiphilic and can act as surfactants in a similiar way detergents do. They can adsorb at air-water interface and lower the surface tension of the solution which allows formation of the foam. This process might lead to protein denaturation, so when handling protein solution you should avoid foaming.
Dawid
Hi Som,
An important add-on to the previous answer: shaking can induce mechanical denaturation of proteins.
As denatured proteins often display prominent surfactant properties, they give rise to foam in aqueous solutions.
One paradigmatic example from everyday life is sea foam.
Best,
Metello
Contributing to previous answers: tertiary structure of a protein answers to the aqueous solvent, thus the folding tries to bury as many hydrophobic residues as possible. When you shake a protein solution you favor the exposure of these residues and since these residues are able to interact with air; you lose the tertiary structure.
Another familiar example of protein foaming due to agitation with air is egg white meringue.
The protein lowers the surface tension of the liquid, and its Gibbs elasticity and cohesion as a large molecule stabilizes the foam. Proteins differ in their effect on surface tension reduction.
Not a good thing, can affect 3° and 4° structure, hence activity.
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