Peptide Bond


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Related to Peptide Bond: Dipeptide bond

peptide bond

[′pep‚tīd ‚bänd]
(organic chemistry)
A bond in which the carboxyl group of one amino acid is condensed with the amino group of another to form a ‒CO·NH‒ linkage. Also known as peptide linkage.

Peptide Bond

 

(also peptide linkage), an amide bond that arises during the formation of proteins and peptides when the α-amino group (—NH2) of one amino acid interacts with the α-carboxyl group (—COOH) of another amino acid:

where R1 and R2 are molecular parts that differ from one amino acid to another. The —CO—NH— group in proteins exhibits a keto-enol tautomerism.

The presence of peptide bonds in proteins and peptides was first proposed by A. Ia. Danilevskii and E. Fischer and later confirmed by chemical and physical data. Owing to tautomerism, the peptide bond exhibits a partial (40-percent) similarity to the double (conjugate) bond, which is indicated by the shorter length (1.32 A) of the peptide bond than of the single —C—N— bond (1.47 Å). The partially conjugate nature of the —C—N— bond determines the flat configuration of the —CO—NH— group (all four atoms are coplanar) and the existence of the trans and cis forms:

The greater stability of the trans form has been proved experimentally.

The enzymatic formation of peptide bonds in living cells occurs during protein biosynthesis. Laboratory methods have been developed for the chemical and enzymatic synthesis and cleavage of peptide bonds, thereby making it possible to synthesize a number of biologically active peptides and to determine the amino-acid sequence for many proteins and peptides.

N. N. ZAITSEVA

References in periodicals archive ?
Djuran, "A study of the reactions of methionine- and histidine-containing peptides with palladium(II) complexes: the key role of steric crowding on palladium(II) in the selective cleavage of the peptide bond," Polyhedron, vol.
The term "peptidase" is recommended by the Nomenclature Committee of International Union of Biochemistry and Molecular Biology to be used as synonymous with "peptide hydrolase" for any of the enzyme that hydrolyzes peptide bonds [1, 3].
The authors suggest that, due to the specificity of the two enzymes, the same protein was hydrolyzed at different peptide bonds, resulting in a different composition of the hydrolysates.
To prove the theory, Watanabe and his team recreated the formation of peptide bonds in vitro by using a type of ribosomal RNA they created from E.
Statistical surveys of peptide bond geometrical parameters (bond and dihedral angles) were performed on ensembles of protein structures reported in the PDB (release of March 2016).
Dependence of the acidity of the C-terminal carboxyl group on the conformation of the C-terminal peptide bond," Journal of the American Chemical Society, vol.
On a weight basis, hexaglycine had higher reactivity, but this is explained by a lower mass per amino acid residue, and per mole of peptide bond, it had a reactivity similar to that of albumin.
The chromatographic process is monitored at 214 nm, which measures "peptide bond" absorbance; there thus is no bias in analyte detection under these analysis conditions.
The stability and degradation pathway of recombinant human parathyroid hormone: deamidation of asparaginyl residue and peptide bond cleavage at aspartyl and asparaginyl residues.
However, protein-bound homocystamide could not be measured by this conventional method because the peptide bond is refractory to chemical reduction.
Dissociation of the peptide bond on the amino side of a Pro residue is highly favored, as shown in both high-energy tandem double-focusing CID studies and low-collision-energy CID with quadrupole and hybrid instrumentation [17-21].
Request for a Free Sample Report of Concerned Market - https://www.factmr.com/connectus/sample?flag=S&rep_id=378 Peptides are amino acids' short chains connected through peptide bonds. Peptides are molecules that are commonly known as proteins, whose functions are determined on the basis of the amino acid sequence and size.