Protein (chemistry)

Proteins are large organic molecules made of amino acid chains, folded into intricate three-dimensional structures that perform nearly all the work inside living cells.

Every organism relies on proteins to carry out its chemistry. Some proteins catalyze chemical reactions as Enzymes, others transport molecules, provide structure, or regulate processes. The specific sequence of amino acids—determined by genes—dictates how a protein folds and what it can do. This relationship between sequence and structure is one of biology's deepest puzzles: the same 20 amino acids, arranged in different orders, create an almost infinite diversity of function.

Proteins fold spontaneously, guided by chemical forces, into shapes ranging from tight spirals to sprawling tangles. Many perform their work only when bound to other molecules or when part of larger protein complexes. Misfolded proteins can cause disease, from Alzheimer's disease to Prion diseases.

Understanding proteins unlocked the genetic code and revolutionized medicine. X-ray crystallography and Cryo-electron microscopy let scientists see protein structures at atomic resolution. Today, computational tools and AI predict protein shapes from sequence alone—a breakthrough that promises to accelerate drug discovery and synthetic biology.

Related

Amino acids, Enzymes, Gene expression, Proteomics, Protein folding, Structural biology