Proteins are the most abundant and diverse organic molecules present in living organisms. The physiological process that takes place in an organism is mediated or assisted by proteins. The name protein has its origin from the Greek word Proteos, which could be translated to ‘primary’ or ‘holding first place’.
A single cell contains thousands of proteins, each with a unique structure and function. Though their structures and functions vary, all proteins are made up of a fundamental building block called amino acids. The proteins are made of one or more chains of covalently linked amino acids through peptide bonds.