Why are non-covalent interaction between substrate and active site important?

The active site and the substrate interaction is transient and non covalent. The distribution of charge of the active site and the substrate must be complementary of one another. The meaning of the complementary is that the postive and negative charge of should be cancelled out by one another or there will be repulsion in active and the substrate. This repulsive force will separate the site and substrate.

The non covalent bond such as vander walls, hydrogen bond and other interaction allow the the active site to get free after the reaction as these bonds are easy to separated after the reaction.

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