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How are ribozymes different from protein enzymes?

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A multi-panel diagram illustrates how a substrate binds to an enzyme's active site through induced fit, leading to product formation, and shows how non-substrates and allosteric regulators can alter enzyme activity by binding to different sites on the enzyme. — Enzyme In the induced-fit theory of enzyme-substrate binding, a substrate approaches the surface of an enzyme (step 1 in box A, B, C) and causes a change in the enzyme shape that results in the correct alignment of the catalytic groups (triangles A and B; circles C and D represent substrate-binding groups on the enzyme that are essential for catalytic activity). The catalytic groups react with the substrate to form products (step 2). The products then separate from the enzyme, freeing it to repeat the sequence (step 3). Boxes D and E represent examples of molecules that are too large or too small for proper catalytic alignment. Boxes F and G demonstrate binding of an inhibitor molecule (I and I′) to an allosteric site, thereby preventing interaction of the enzyme with the substrate. Box H illustrates binding of an allosteric activator (X), a nonsubstrate molecule capable of reacting with the enzyme.

Ribozymes and protein enzymes are both biological catalysts that regulate chemical reactions within cells, but they differ fundamentally in their chemical composition and structural diversity.123

Chemical Composition: Protein enzymes are composed of chains of amino acids, whereas ribozymes are molecules of RNA consisting of linear chains of nucleotides.23
Structural Diversity: Protein enzymes are generally more diverse and capable of complex shape changes because they utilize a wider variety of amino acid side chains. This allows them to form highly efficient functional surfaces. Ribozymes, while also folding into unique three-dimensional shapes to create active sites, are less frequently used as catalysts in modern cells compared to proteins.2
Evolutionary Context: It is hypothesized that ribozymes preceded protein enzymes during evolution, potentially catalyzing essential chemical reactions in an early "RNA world" before the development of protein-based life.12

While both types of molecules function by lowering the activation energy of reactions, protein enzymes are the primary catalytic agents in modern organisms, whereas ribozymes perform more specialized roles, such as self-splicing or cleaving precursor tRNA.123