Isoprenoidien

Isoprenoids, also known as terpenoids, are a large and diverse class of organic compounds derived from units of isoprene, a five-carbon molecule with the formula C5H8. These compounds are ubiquitous in nature and play crucial roles in various biological processes. The basic building block of isoprenoids is isoprene, which can be polymerized in different ways to form a vast array of structures. These structures range from simple acyclic molecules to complex polycyclic systems.

Isoprenoids are classified based on the number of isoprene units they contain. For instance, monoterpenoids consist of two isoprene units, sesquiterpenoids of three, diterpenoids of four, and so on. Higher isoprenoids include triterpenoids (six isoprene units) and tetraterpenoids (eight isoprene units), which form carotenoids. Polymers of isoprene units are also considered isoprenoids, such as rubber.

These compounds exhibit a wide range of functions. In plants, they serve as pigments (carotenoids), fragrances and flavorings (essential oils), hormones (gibberellins), and defensive compounds. In animals, isoprenoids are vital components of cell membranes (sterols), vitamins (vitamins A, E, and K), and signaling molecules. Cholesterol, a crucial sterol, is a well-known example of a complex isoprenoid. The biosynthesis of isoprenoids follows specific metabolic pathways, primarily the mevalonate pathway and the methylerythritol phosphate (MEP) pathway, which convert simple sugars into isoprene precursors. The study of isoprenoids is important in fields such as biochemistry, pharmacology, and agriculture due to their diverse applications and biological significance.