peptide Related Biological Terms

A compound formed by incomplete hydrolysis of a protein, or by elimination of the elements of water from between the -carboxy and the -amino groups of -amino acids to form a linear polymer.

An oligomer of β-amino acids Borman, S. (1997) Chem. Engin. News 75(24), 32-35

An amide bond between amino acids that employs a non--amino or a non--carboxy group, e.g. the -carboxy--amino cross-link of hard fibrin clots.

A description of helix-helix interactions in which side chains of two parallel, adjacent helices closely interact due to complementary shapes and electrostatic interactions, e.g. the leucine zipper motif of the fos and jun heterodimers. O'Shea, E.K., Lumb, K.J. and Kim, P.S. (1994) Curr. Biol. 3, 658-667

The amide bond formed by condensation of the -carboxy group of one amino acid with the -amino group of another; the bond that joins together the amino acid residues that comprise a protein, peptide or polypeptide.

The part of a ribosome that binds the growing peptidyl-tRNA before the peptidyl group is transferred to the next amino acyl residue which is held at the amino acyl site as its tRNA ester.

For purposes of identification of polypeptides that have a high affinity for a target structure, the assortment of, e.g., the 520 to 720 penta- to hepta-peptides that may be incorporated into a phage genome and expressed on the phage surface. (see phage display)Cortese, R., Monaci, P., Luzzago, A. et al.(1996) Curr. Opin. Biotechnol. 7, 616-621; Zhao, H. and Arnold, F.H. (1997) Curr. Opin. Struct. Biol. 7, 480-485

A strategy for determination of the specificity of a soluble peptide. random collections of all the possible oligopeptides of a certain length, preceded by all the possible dipeptide sequences, are prepared; for example, if hexamers, there will be 400 (202) sets, each with the two known N-terminal residues followed by a random tetrapeptide; each of the 400 sets will consist of 160000 (204) hexapeptides. Each of the 400 is tested in an assay or bioassay, e.g. binding, inhibition, vasoconstriction. The successful set is refined by placing at the first of the random positions each of the amino acids, so there will be 20 sets of hexapeptides, each with a known tripeptide sequence followed by random tripeptide sequences. These are again tested in the assay system to further narrow the selection. Eventually the most favoured hexapeptide sequence is identified. A related strategy is positional scanning SPCL, in which a single amino acid is placed in each of the positions of the oligopeptide, a hexapeptide in the example, with each of the other five positions being filled at random by other amino acids. Each of these sub-libraries is assayed for selection and further refinement as in the original strategy. Houghten, R.A. (1994) Methods Companion Methods Enzymol. 6, 354-360

A small gene within the attenuator control region of repressible amino acid operons. translation of a specific leader peptide tests for the concentration of a specific amino acid or set of amino acids in the cell. If the concentration is high transcription is terminated in the attenuator, if low continued leading to the production of enzymes for amino acid synthesis and hence more amino acid. See leader transcript.

A peptide with attached lipids or a mixture of lipids and peptides.

A chain of linked Amino acids; a protein.