Arsenals of Pharmacotherapeutically Active Proteins and Peptides: Old Wine in a New Bottle

The word protein is derived from term proteios meaning either first or preeminent. This term was coined by Berzelius, a Swedish chemist, in 1838. Proteins are highly diverse molecules composed of amino acids. The world of peptides and proteins are fascinating. Proteins are building blocks of every organism including plants, bacteria, and fungi. Amino acids can be simply referred to as monomers of proteins. The various amino acids are linked together to form peptides or proteins. Many proteins involved in redox reactions are selenoproteins. Synthesis of selenoproteins comprises the inclusion of selenocysteine (Sec) in the proteins during translation. Selenium is obtained by the cell in the form of selenite or selenate. Polar molecules are those which have an affinity for water or are hydrophilic. Non-polar molecules are hydrophobic in nature. The amino acids exhibit a wide range of physical properties.