Question

Protein shape is critical for its function. Give two biological examples of how a protein changing its shape affects its function.

Answer 1

Each protein has specific amino acid sequence and specific three dimensional structure. This three dimensional structure is responsible for particular shape of protein and determines its specific function. This specific shape is responsible for its function, if this shape is changed or altered, then protein is not able to perform it's function . For example

--a hormone has specific sequence so that they have specific amino acid composition at their hormone receptor binding domain. So if there is change in the shape of the hormone so it will change its receptor binding domain . Now in this condition it will not able to bind and not able to perform its function.

-- second example is change in the activity of enzyme activity. Each enzyme has specific three dimensional structure. Due to three dimensional structure it has specific amino acid at its active sites. So it will perform specific catalysis. So if structure of this enzyme is altered than it will change the specific amino acid at active site , now this enzyme will not able to perform its function.