peptide bond

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Related to Protein backbone: Peptide link

bond

 [bond]
the linkage between atoms or radicals of a chemical compound, or the symbol representing this linkage and indicating the number and attachment of the valencies of an atom in constitutional formulas, represented by a pair of dots or a line between atoms, e.g., H—O—H, H—C≡C—H or H:O:H, H:C:::C:H.
coordinate covalent bond a covalent bond in which one of the bonded atoms furnishes both of the shared electrons.
covalent bond a chemical bond between two atoms or radicals formed by the sharing of a pair (single bond), two pairs (double bond), or three pairs of electrons (triple bond).
disulfide bond a strong covalent bond, —S—S—, important in linking polypeptide chains in proteins, the linkage arising as a result of the oxidation of the sulfhydryl (SH) groups of two molecules of cysteine.
high-energy phosphate bond an energy-rich phosphate linkage present in adenosine triphosphate (ATP), phosphocreatine, and certain other biological molecules. On hydrolysis at pH 7 it yields about 8000 calories per mole, in contrast to the 3000 calories yielded by phosphate esters. The bond stores energy that is used to drive biochemical processes, such as the synthesis of macromolecules, contraction of muscles, and the production of the electrical potentials for nerve conduction.
high-energy sulfur bond an energy-rich sulfur linkage, the most important of which occurs in the acetyl-CoA molecule, the main source of energy in fatty acid biosynthesis.
hydrogen bond a weak, primarily electrostatic, bond between a hydrogen atom bound to a highly electronegative element (such as oxygen or nitrogen) in a given molecule, or part of a molecule, and a second highly electronegative atom in another molecule or in a different part of the same molecule.
ionic bond a chemical bond in which electrons are transferred from one atom to another so that one bears a positive and the other a negative charge, the attraction between these opposite charges forming the bond.
peptide bond the —CO—NH— linkage formed between the carboxyl group of one amino acid and the amino group of another; it is an amide linkage joining amino acids to form peptides.

pep·tide bond

the common link (-CO-NH-) between amino acids in proteins, actually a substituted amide, formed by elimination of H2O between the -COOH of one amino acid and the H2N- of another. Compare: eupeptide bond, isopeptide bond.

peptide bond

n.
The chemical bond between carboxyl groups and amino groups of neighboring amino acids, forming an amide group and constituting the primary linkage of all protein structures.

pep·tide bond

(pep'tīd bond)
The common link (-CO-NH-) between amino acids in proteins, formed by elimination of H2O between the -COOH of one amino acid and the H2N- of another.

peptide bond

A covalent bond formed between amino acids during protein synthesis. The OH- on a carbon atom links with the H- on a nitrogen atom to form a water molecule which is given off as each peptide bond is formed. Amino acids linked by peptide bonds form dipeptides, tripeptides or polypeptides.
Peptide bondclick for a larger image
Fig. 249 Peptide bond . Molecular structure. R1 R2 distinctive side-chains for different amino acids.

peptide bond

a covalent C arbon-N itrogen bond that joins the carboxyl group of one AMINO ACID to the amino group of another (with loss of a water molecule). See Fig. 249 . Many amino acids are joined by peptide bonds to form a POLYPEPTIDE CHAIN.

pep·tide bond

(pep'tīd bond)
The common link (-CO-NH-) between amino acids in proteins.
References in periodicals archive ?
Using statistical analyses of a recent ensemble of structures retrieved from the Protein Data Bank (PDB), we here extended these analyses to the other protein backbone parameters.
The analyses dealt with all six bond angles involving nonH atoms of the protein backbone ([C.sup.[beta]][C.sup.[alpha]]C, N[C.sup.[alpha]][C.sup.[beta]], [C.sup.[alpha]]CO, [C.sup.[alpha]]C[N.sup.+1], OC[N.sup.+] , and [C.sup.-1]N[C.sup.[alpha]]) and two parameters that describe the peptide bond distortions ([DELTA][omega] and [[theta].sub.C]) (Figure 1).
Bax, "Empirical correlation between protein backbone conformation and C.alpha.
Bax, "Protein backbone chemical shifts predicted from searching a database for torsion angle and sequence homology," Journal of Biomolecular NMR, vol.
Since there is evidence that proteins have certain conducting or semiconducting properties, a charge, moving through the protein backbone and passing different energy stages caused by different amino acid side groups, can produce sufficient conditions for a specific electromagnetic radiation or absorption.
The defective GALNT3 gene encodes UDP-Ga1NAc transferase 3 (GALNT3), responsible for the transfer of UDP-Ga1NAc to Thr/Ser to the protein backbone. GALNT3 is highly expressed in human pancreas, skin, kidney, and testis and weakly expressed in prostate, ovary, intestine, and colon (24).
This will be followed by detailed computational, biophysical, crystallographic and site-saturation mutagenesis analysis to isolate critical design features.-develop a new computational design strategy, which expands on the crick coiled-coil parametrization and allows to rationally build non-ideal helical protein backbones at specified regions in the desired structure.
Protein backbones can rotate around two bonds per peptide linkage, or [2.sup.(N-1)] bonds in a peptide containing N amino acid residues.
Amide hydrogens along protein backbones are labile and will exchange readily with deuterium when a protein is dissolved in [D.sub.2]O (Ehring 1999; Smith & Zhang 1994; Smith et al.
Automatic Modeling of Protein Backbones in Electron Density Maps via Prediction of C[alpha] Coordinates.