Simple Protein vs. Conjugated Protein — What's the Difference?

Simple Proteins refer to proteins that consist only of amino acid residues. They are basic in nature and do not have any non-protein constituents attached. In contrast, Conjugated Proteins are complex proteins that contain one or more non-protein components, termed prosthetic groups, in addition to their amino acid chains. These additional components give Conjugated Proteins distinct properties and functionalities.

In the realm of biochemistry, understanding the distinction between Simple Protein and Conjugated Protein is vital. A Simple Protein, when hydrolyzed, will yield only amino acids, which are the fundamental building blocks of all proteins. On the other hand, hydrolyzing a Conjugated Protein yields both amino acids and its non-protein constituents, revealing its composite nature.

The functions and characteristics of Simple Proteins are primarily determined by the sequence of their amino acids. They perform a myriad of roles in organisms, including serving as enzymes, hormones, and structural proteins. Conjugated Proteins, given their additional components, often have specialized functions. These non-protein parts can be lipids, carbohydrates, or even metal ions, allowing the Conjugated Proteins to perform roles not possible for Simple Proteins alone.

For example, hemoglobin, which transports oxygen in the blood, is a Conjugated Protein because it contains an iron-containing heme group. Without this non-protein part, hemoglobin wouldn't function efficiently. In contrast, albumin, found in egg whites, is a Simple Protein and functions primarily as a storage and transport protein without the need for additional components.