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Published on: January 26, 2016
New cyclic peptide proteasome inhibitors
Anna Baldisserotto1, Mauro Marastoni, Riccardo Gavioli
1Department of Pharmaceutical Sciences and Centre of Biotechnology, University of Ferrara, 44100 Ferrara, Italy.
Bioorganic & Medicinal Chemistry Letters
|March 3, 2009
Summary
New vinyl ester cyclopeptide analogues show promise as proteasome inhibitors. These compounds exhibit nanomolar potency, resist degradation, and can enter cells, offering potential therapeutic applications.
Area of Science:
- Medicinal Chemistry
- Molecular Biology
- Biochemistry
Background:
- Cyclopeptides are a known class of linear prototype inhibitors.
- Previous development focused on linear inhibitors.
Purpose of the Study:
- To synthesize and study a new series of vinyl ester cyclopeptide analogues.
- To investigate their potential as proteasome inhibitors.
Main Methods:
- Synthesis of vinyl ester cyclopeptide analogues.
- Linking the Leu-VE pharmacophore to the C-terminal glutamic acid residue.
- Assay of caspase-like proteasome activity.
Main Results:
- The best analogues inhibited proteasome activity at nanomolar concentrations.
- Compounds demonstrated good resistance to proteolysis.
- The analogues showed capacity for cell membrane permeation.
Conclusions:
- The novel vinyl ester cyclopeptide analogues are potent inhibitors of proteasome caspase-like activity.
- These analogues possess favorable pharmacokinetic properties, including stability and cell permeability.
- This class of compounds holds potential for therapeutic development.
Related Concept Videos
The Proteasome
Eukaryotic cells can degrade proteins through several pathways. One of the most important among these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
The Proteasome
Eukaryotic cells can degrade proteins through several pathways. One of the most important amongst these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
The Proteasome
Eukaryotic cells can degrade proteins through several pathways. One of the most important amongst these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
The Proteasome Structure
The ubiquitin-proteasome pathway is a well-known mechanism utilized by eukaryotic cells to remove cytoplasmic proteins that are misfolded, damaged, or no longer needed. In this pathway, the protein that needs to be eliminated undergoes a process called ubiquitination, where a chain of ubiquitin molecules is attached to the 48th lysine residue of the target protein. This ubiquitin modification helps the proteasome distinguish between a target protein and a healthy protein.
The proteasome is an...
The proteasome is an...
Caspases
Caspase, a family of cysteine proteases, serve as effectors in apoptosis. The ced3 gene in C.elegans was first identified to be involved in apoptosis. This gene encodes the ced-3 caspase that is similar to the interleukin-1-beta converting enzyme or ICE in mammals. In addition to apoptosis, caspases also function in the inflammatory response. Inflammatory caspases are essential in activating pro-inflammatory cytokines that recruit immune cells and block the replication of pathogens inside cells.
Transducer Mechanism: Enzyme-Linked Receptors
Enzyme-linked receptors are cell-surface receptors acting as an enzyme or associating with an enzyme intracellularly. They make excellent drug targets. Drugs can bind to the extracellular ligand-binding domain or directly affect their enzymatic domain and alter their activity.
Major types that are helpful drug targets include:
Major types that are helpful drug targets include:

