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

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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.
All peptide bonds in short peptides would be available for immediate interaction with copper, as none of the peptide bonds will be buried within a globular structure; no denaturation would be required before interaction with copper.
DH, defined as the percentage of peptide bonds cleaved by protease, has been frequently applied as the index of DH [19,20].
2, designating it as a hydrolase (EC 3), which acts on peptide bonds (EC 3.
A peptide is a short polymeric compound based on a-amino acids connected by peptide bonds.
The peptide bonds are formed through condensation reactions in which a water molecule is lost.
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When vancomycin works, it inhibits Gram-positive bacterial cell wall assembly by binding to the terminal D-Ala-D-Ala of peptidoglycan building blocks, a specifically configured chain of amino acids linked by peptide bonds.
1] by peptide bonds of protein molecules and lactose measurement based on absorbance at 1,042 [cm.
When the researchers introduced molecules presumed to dock at the location where peptide bonds form, they confirmed that the site lies at one end of a tunnel structure previously proposed to reside within the ribosome.
The bleach breaks peptide bonds, inactivating the allergens so they no longer trigger an allergic reaction.