Peptide name : AKPF dimer, Smac-1

Source/Organism : SMAC

Linear/Cyclic : Linear

Chirality : L

Peptide length: Not available

C-terminal modification: Linear

N-terminal modification : Not found

Non-natural peptide information: None

Assay type : Not specified

Assay time : Not found

Activity : IC50 : 3.93 ± 1.1 nM

Cell line : MDA-MB-231

Cancer type : Not specified

Other activity : Not found

Amino Acid Composition Bar Chart : Not available

Molecular mass : Not available

Aliphatic index : Not available

Instability index : Not available

Hydrophobicity (GRAVY) : Not available

Isoelectric point : Not available

Charge (pH 7) : Not available

Aromaticity : Not available

Molar extinction coefficient (cysteine, cystine): Not available

Hydrophobic/hydrophilic ratio : Not available

hydrophobic moment : Not available

Missing amino acid : Not available

Most occurring amino acid : Not available

Most occurring amino acid frequency : Not available

Least occurring amino acid : Not available

Least occurring amino acid frequency : Not available

3D-structure: Not available

Secondary structure fraction (Helix, Turn, Sheet): Not available

SMILES Notation: Not available

Molecular descriptors: Not available

ADMET properties: Not available

1 : Nikolovska-Coleska Z, et al. Design and characterization of bivalent Smac-based peptides as antagonists of XIAP and development and validation of a fluorescence polarization assay for XIAP containing both BIR2 and BIR3 domains. Anal Biochem. 2008; 374:87-98. doi: 10.1016/j.ab.2007.10.032

Paper title : Design and characterization of bivalent Smac-based peptides as antagonists of XIAP and development and validation of a fluorescence polarization assay for XIAP containing both BIR2 and BIR3 domains.

Doi : https://doi.org/10.1016/j.ab.2007.10.032

Abstract : XIAP (X-chromosome-linked inhibitor of apoptosis protein) is an inhibitor of apoptosis by binding to and inhibition of caspase-3 and caspase-7 through its BIR2 domain and caspase-9 through its BIR3 domain. Smac (second mitochondria-derived activator of caspases) protein is an endogenous antagonist of XIAP. Smac forms a dimer and concurrently binds both the BIR2 and BIR3 domains in XIAP, functioning as a highly efficient and potent cellular inhibitor of XIAP. In this article, we have designed and synthesized a bivalent Smac-based ligand (Smac-1) and its fluorescent labeled analogue (Smac-1F) and characterized their interaction with different constructs of XIAP. Our study demonstrates that bivalent Smac-based ligands bind concurrently to both the BIR2 and BIR3 domains of XIAP and are more than 500 times more potent than the corresponding monovalent Smac-based ligands. Bivalent Smac-based ligands also function as much more potent antagonists of XIAP than do the corresponding monovalent Smac-based ligands in cell-free functional assays. Using Smac-1F and XIAP containing both BIR2 and BIR3 domains, we also developed and validated a new fluorescence polarization-based assay. Hence, our designed bivalent Smac-based peptides mimic the mode of dimeric Smac protein in their interaction with XIAP containing both BIR2 and BIR3 domains and achieve extremely high potency in binding and functional assays. Our study provides new insights into the mode of action of bivalent Smac ligands targeting XIAP and a basis for the design and development of cell-permeable, bivalent Smac mimetics.