Explain how a change in the primary structure may result in a non functional enzyme

A change in the primary structure means there has been a change in the amino acid sequence.This may cause different hydrogen bonding to occur, leading to a different secondary structure.This may lead to different folding due to different hydrogen, ionic and disulphide bridge interactions. This may lead to a different tertiary structure, and therefore a different active site shape.Therefore the active site may no longer be complimentary to the substrate meaning that enzyme substrate complexes cannot form. Therefore, the enzyme is not functional.
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