N-Terminal Acetylation and C-Terminal Amidation of Peptides
Description
Chemically synthetised peptides carry free amino and carboxy termini, being electrically charged in general. In order to remove this electric charge, peptide ends are often modified by N-terminal acetylation and/or C-terminal amidation.
Advantages
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peptide ends are uncharged, compared to standard synthetic peptides, so they mimic natural peptides; permeability of cells increases
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stability toward digestions by aminopeptidases is enhanced
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peptide ends are blocked against synthetase activities
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acetylated peptides serve as optimized enzyme substrates
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amidation of peptides enhances activity of peptide hormones
Applications:
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intracellular, in-vivo assays (e.g., microbiology)
- substrates in enzyme assays
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in-vivo or in-vitro functional studies (activity of peptides or peptidic molecules)
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ELISA assays – in order to minimize influences of charged C- or N-termini with ELISA binding characteristics
Please note:
Both N-terminal acetylation and C-terminal amidation block the respective terminus for coupling of additional modifications, such as dyes, functional groups, etc. However, when requiring additional terminal modifications, the only possibility is to couple these modifications via a functional group within the side-chain of the N- or Cterminal amino acids.