Proteins

Proteins are the most diverse class of macromolecule found in the cell, making up roughly two-thirds of a cell's total dry mass. The term 'protein' was coined by the chemist Gerardus Johannes Mulder, and derives from the Greek word 'proteos', meaning 'of the first rank' - a fitting name given how central proteins are to nearly every cellular process, from catalysing reactions as enzymes to providing structure, transport, defence and chemical signalling. Proteins are built from amino acids, roughly 20 of which occur naturally and are linked tog …