Peptide Glossary

This glossary lists terms you may come across when reading about peptides, peptide synthesis and amino acids.

Two or more amino acids chained together by a bond called a "peptide bond".

Peptide Synthesis
A biological or chemical process in which amino acids are added stepwise to a chain by the formation of a peptide bond between a carboxyl group on one amino acid and a free amino group on another amino acid. The formation of each peptide bond is energetically favorable because the growing carboxyl terminus is activated by the covalent attachment of a tRNA molecule.

An organic high polymer that is an amphoteric biopolymer consisting of amino acids joined by peptide linkages. Genetic code determines the order of the twenty possible amino acids used in protein synthesis, and thus the protein's structure and function. Proteins are the principal constituents of cellular material and serve as enzymes, hormones, structural elements, and antibodies. Protein is involved in electron and oxygen transport, muscle contraction, and other bodily activities.

Cyclic Peptides
Peptides in which the amino-acid sequence forms a ring structure rather than a straight chain, such as the antibiotics tyrocidin and gramicidin.

Amino Acid
An amino acid is any molecule that contains both amine and carboxyl functional groups. Alpha-amino acids are the building blocks from which proteins are constructed.

Protein Synthesis
Synthesis of a protein, directed by the genetic code, which occurs by translation of mRNA into protein via tRNA. The ribosome attaches to the mRNA, using it as a template.

Peptide Sequence
The order in which amino acid residues connected by peptide bonds.

Peptide Bond
The amide linkage between the alpha-amino group of one amino acid and the alpha-carboxyl group of another, with the elimination of a molecule of water.

Peptide Mapping
A general term for methods used to identify unique proteins or nucleic acids by breaking them up with enzymes and looking at the resulting pattern of their amino acid or nucleotide base sequences.

Peptide Mimetics
The design of structurally similar organic compounds.

Peptide Fingerprint
A chromatographic pattern produced by partial hydrolysis of a protein and 2-D mapping of the resulting peptide fragments.

Peptide Library
A systematic combination of different peptides in a large number. It is a powerful tool for drug discovery, structural studies and other applications. Solid phase peptide synthesis, along with other methods, has been successfully used to prepare peptide libraries.