c-terminal amidation of peptides are energetically costly but critical for membrane-active antimicrobial peptides - C-terminalamides mark proteins for degradation via SCF/FBXO31 NH4Cl, alkylammonium chloride (RNH3Cl) and semicarbazide hydrochloride

C-terminal amidationmass shift C-Terminal Amidation of Peptides: Enhancing Bioactivity and Stability

C-terminal amidation of peptides is a crucial post-translational modification that significantly impacts their biological activity, stability, and interaction with cellular membranes.The process is very flexible in that it may be adapted to any type of enzymatic synthesis and lend itself toC-terminal amidation of all types of peptides. This process involves converting the carboxyl group at the C-terminus of a peptide into an amide group. The presence of this C-terminal amide is a common feature across many naturally occurring bioactive peptides, including numerous peptide hormones and antimicrobial peptides (AMPs)作者：IF Eggen·2008·被引用次数：2—The present invention relates to a process for theamidation of C-terminal estersor acids of peptide substrates in solution-phase synthesis .... This modification is not merely structural; it is often essential for the full biological function of these molecules, playing a vital role in receptor binding and membrane disruption mechanisms作者：IF Eggen·2008·被引用次数：2—The present invention relates to a process for theamidation of C-terminal estersor acids of peptide substrates in solution-phase synthesis ....

The transformation from a free carboxyl group to a C-terminal amide neutralizes the negative charge typically found at the peptide's C-terminus. This charge neutralization is a key factor in enhancing receptor binding affinity for many bioactive peptides.作者：DJ Merkler·1994·被引用次数：305—Structure-activity data for 45 bioactivepeptidesshow that theC-terminalamide is required for the full biological activity of most amidatedpeptidehormones. Furthermore, this modification can protect peptides from degradation by exopeptidases, enzymes that cleave amino acids from the N-terminus, thereby extending their circulating half-life and improving their therapeutic potentialThe effect of amidation on the behaviour of antimicrobial .... Consequently, C-terminal amidation is extensively employed in the development of therapeutic peptides to boost their efficacy and shelf-life作者：S Hosseini·2013·被引用次数：40—Thus, the effect ofC-terminal amidationon the process of biomineralization is unknown. In our study, a natural motif sequence consisting of 13 amino acids ....

Methods for Achieving C-Terminal Amidation

The synthesis and modification of peptides have seen continuous advancements, with various chemical and enzymatic approaches developed for C-terminal amidation.

* Chemical Synthesis: Chemical methods offer flexibility and scalability. One common strategy involves the use of reagents like ammonia or ammonium chloride to introduce the amide group.作者：DJ Merkler·1994·被引用次数：305—Structure-activity data for 45 bioactivepeptidesshow that theC-terminalamide is required for the full biological activity of most amidatedpeptidehormones. Other chemical approaches utilize coupling reagents such as EDC.HCl, DIC, HATU, DMAP, HBTU, or TBTU in conjunction with amine sources. For instance, DMAP has been shown to catalyze the reaction of peptides with isocyanates to form C-terminal amides.C-Terminal Amidation: Structural Insights into Enhanced ... More recent developments include the use of small-molecule C-terminal amidation tags based on phosphonate or aliphatic moieties, as well as propargyl-assisted selective amidationA vast number of naturally occurringpeptidehormones possess aC-terminalamide, which is vital for their structure and biological activity.. These chemical routes can be applied to peptides synthesized in solution or through solid-phase synthesis, including the amidation of C-terminal peptide esters or acids.One-pot and sustainable liquid-phase peptide extension ...

* Enzymatic Synthesis: Enzymatic methods provide a highly specific and often milder alternative for peptide amidation. Enzymes such as peptidylglycine $\alpha$-amidating monooxygenase (PAM) are naturally involved in this post-translational modification, catalyzing the final essential step in the biosynthesis of several peptide hormones. Enzymatic approaches can be adapted for the C-terminal amidation of a wide array of peptide substrates, offering a route for producing complex or sensitive peptide structures.

Significance and Applications of C-Terminal Amidation

The impact of C-terminal amidation extends to various peptide classes and applications:

* Peptide Hormones: A significant portion of known peptide hormones, such as oxytocin and vasopressin, feature a C-terminal amide.One-pot and sustainable liquid-phase peptide extension ... This modification is critical for their biological activity, influencing their interaction with specific receptors and their overall physiological effects.Revealing C-terminal peptide amidation by the use of the ...

* Antimicrobial Peptides (AMPs): Many naturally occurring AMPs, particularly membrane-disrupting types, are characterized by C-terminal amidation.2016年9月22日—I am thinking of usingliquid ammonia or ammonium chlorideto amidate the terminal, chemicals I have available are EDC.HCl, DIC, HATU, DMAP, HBTU, TBTU, HOBt. This modification is often integral to their mechanism of action, affecting their ability to interact with and permeabilize bacterial membranes. Studies have shown that C-terminal amidation can influence the strength of interactions between peptides and lipid bilayers, potentially leading to membrane disruptionShould My Peptide Be Amidated?.

* Therapeutic Peptides: In drug development, C-terminal amidation is a strategic modification to enhance the pharmacokinetic and pharmacodynamic properties of peptide-based therapeutics. By increasing resistance to enzymatic degradation and improving receptor binding, amidated peptides can achieve higher efficacy and longer duration of action, making them more suitable for clinical use.

* Structural and Functional Insights: Research into C-terminal amidation provides valuable structural insights into peptide behavior. For example, it can influence intramolecular hydrogen bonds within peptides, affecting their overall conformation and stability. Understanding these effects is crucial for designing peptides with desired properties.

In summary, C-terminal amidation is a fundamental peptide modification with profound implications for biological activity and stabilityPreparation of peptides with C-terminal proline amide. Whether achieved through chemical synthesis or enzymatic processes, this transformation is indispensable for the function of many natural peptides and a key strategy in the design of advanced peptide therapeutics.