Enzymes as Catalysts. Structure-Functionality Relationships

The main types of interactions responsible for the three-dimensional structure of proteins are (Haschemeyer and Haschemeyer 1973)  

Catalysis takes place in a small portion of the enzyme called the active site, which is usually formed by very few amino acid residues, while the rest of the protein acts as a scaffold. Papain, for instance, has a molecular weight of 23,000 Da with 211 amino acid residues of which only cysteine (Cys 25) and histidine (His 159) 

The requirement of cofactors or coenzymes to perform biocatalysis has profound technological implications, as will be analyzed in section 1.4. 

Enzyme activity, this is, the capacity of an enzyme to catalyze a chemical reaction, is strictly dependent on its molecular structure. Enzyme activity relies upon the existence of a proper structure of the active site, which is composed by a reduced number of amino acid residues close in the three-dimensional structure of 

3 Enzymes according to their cofactor or coenzyme requirements. 1 no requirement 2 cofactor requiring 3 o 

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