Which macromolecule is primarily responsible for the structure and function of enzymes?

Enzymes are biological catalysts that speed up chemical reactions in living organisms, and they are primarily composed of proteins. The structure of enzymes allows them to bind to specific substrates, forming an enzyme-substrate complex, which is crucial for their catalytic function. This structure-function relationship is a defining characteristic of proteins, as their unique sequences of amino acids determine their three-dimensional shape and, consequently, their specific activity in biological processes.

The importance of proteins in enzyme activity stems from their ability to form complex structures, including active sites that facilitate chemical reactions. Unlike carbohydrates, nucleic acids, and lipids, proteins exhibit a high degree of structural variability and complexity, enabling them to perform the diverse range of functions required in biochemical reactions. Each protein, including enzymes, is tailored to interact with specific substrates, further underscoring the role of proteins in enzymatic function. This specificity and functional capability derived from their structure is what makes proteins the primary macromolecule responsible for enzyme activity.