Ribozyme

Part of speech: noun

Definitions

1. An RNA molecule that acts as an enzyme by speeding up specific chemical reactions within a cell without needing protein catalysts
2. A catalytic strand of ribonucleic acid able to cut or join other RNA molecules, functioning like a protein enzyme in living systems
3. A type of ribonucleic acid that folds into a shape allowing it to catalyze biochemical reactions, as proteins usually do in cells

Etymology: Ribozyme is a blend of "ribonucleic acid" and "enzyme," and the two halves tell a story that overturned a central assumption of biology. Enzymes were long defined as protein catalysts, while nucleic acids were thought to carry information and nothing more. A molecule that is both a nucleic acid and a catalyst was therefore a conceptual surprise, and the name packs that surprise into a single word. The "-zyme" ending comes from the Greek "zumē," meaning leaven or ferment, which is why enzymes were originally associated with fermentation. "Ribo-" is a shortened form of "ribose," the sugar that forms the backbone of RNA. Put together, the word describes an RNA molecule that acts as a biological catalyst, speeding up chemical reactions in the way enzymes do.

Synonyms: catalytic RNA