Enzymes are the biocatalysts that are capable of mediating many biological reactions and conversion of element into other intermediate products and so on to the final product. Coming to their activity, total enzyme will not be involved in any conversion of substrate to a product. Only, a specific part of the enzyme named “active site†is involved in the reaction phenomenon. Any modifications at the active site will lead to the activity change of that particular enzyme and even that might make an enzyme to lose its activity totally and permanently. In order to make an enzyme to show its maximum potency in conversion of substrate to desired product, many parameters need to be optimized which include pH, temperature, concentration of enzyme, concentration of substrate, reaction time and even many modifications need to be done at the genetic level of that particular enzyme in order to manipulate the enzyme in all the possible ways to give maximum yield of the desired product yield and desired product quality.