Computational Design of BH3-Mimetic Peptide Inhibitors That Can Bind Specifically to Mcl1 or BclXL: Role of Non-Hot Spot Residues (2024)

PLoS ONE, 2010

Chemistry & Biodiversity, 2005

Anti-apoptotic proteins such as Bcl-XL and Mcl-1 have been reported to be over expressed in most cancer forms and consequently, designing dual inhibitors to the proteins is becoming an important strategy in cancer chemotherapy. Interestingly, the Bcl-XL and Mcl-1 show differential binding affinities with BH3-only peptides of Bim and NOXA, notwithstanding their similar three-dimensional folds. The structural determinants for the differential interactions of the proteins with the BH3-only peptides have been scrutinized using molecular docking and temperature-dependent dynamic studies. The comprehensive analysis of the data from the studies paved a way of designing dual inhibitors to the proteins, on the basis of the chemical structures of ABT-737, which is a highly potent inhibitor to the Bcl-XL. The unique feature of this approach on designing the dual inhibitors to the anti-apoptotic proteins have also been brought into detail through a comparative analysis with a few existing strat...

Evading apoptosis is a hallmark of cancer cells, therefore therapeutic strategies have been developed to induce cell death. BCL2 family protein governs the intrinsic pathway of cell death. Targeting the BH4 domain to modulate the anti-apoptosis activities of BCL2 protein has been established however, BDA366 is the only BH4 binding molecule to be reported. Virtually screening ~ 1,000,000 compounds 11 putative BH4 binding small molecules with binding affinity ~ −84kcal/mol to - 64kcal/mol resulted. Using QM-polarized docking, Induced-fit docking, and QM-MM optimization, a putative binding mode for the top 3 compounds is proposed: compound 139068 interactions with GLU13, MET16, LYS17, ASP31, and GLU42; compound 138967 interactions with ASP10, ARG12, GLU13, HIS20, MET16, and GLU42; compound 38831 interactions with ASP10, ARG12, GLU13, LYS17, and GLU42. MD simulations (NMA) data showed the binding of the three compounds to be stable with low eigenvalues. Electronic properties derived via...

Protein Science, 1997

Proteins: Structure, Function, and Genetics, 1997

International Journal of Biological Macromolecules , 2013

Bcl-2 (B cell lymphoma-2) is an anti-apoptotic member of Bcl-2 family and its overexpression causes development of several types of cancer. The BH3 domain of pro-apoptotic and BH3-only proteins is capable of binding to Bcl-2 protein to induce apoptosis. This binding is the basis for the development of novel anticancer drug which would likely antagonize Bcl-2 overexpression. In this study we have identified BH3 domain of Bax (Bax BH3) as potentially the best Bcl-2 antagonist by performing docking of BH3 peptides (peptides representing BH3 domain of pro-apoptotic and BH3-only proteins) into the Bcl-2 hydrophobic groove formed by BH3, BH1 and BH2 domains (also referred as BH3 cleft). To predict the best small antagonist for Bcl-2, three groups of small peptides (pentapeptide, tetrapeptide and tripeptide) were designed and screened against Bcl-2 which revealed the structural importance of a set of residues playing a vital role in interaction with Bcl-2. The docking and scoring function identified KRIG and KRI as specific pep-tides among the screened small peptides responsible for Bcl-2 neutralization and would induce apoptosis. The applied pharmaco*kinetic and pharmacological filters to all small peptides signify that only IGD has drug-like properties and displayed good oral bioavailability. However, the obtained binding affinity of IGD to Bcl-2 was diminutive. Hence deprotonation, amidation, acetylation, benzoylation, benzylation, and addition of phenyl, deoxyglucose and glucose fragments were performed to increase the binding affinity and to prevent its rapid degradation. Benzoylated IGD tripeptide (IGD bzo) was observed to have increased binding affinity than IGD with acceptable pharmaco*kinetic filters. In addition, stability of Bcl-2/IGD bzo complex was validated by Molecular Dynamics (MD) simulations revealing improved binding energy, salt bridges and strong interaction energies. This study suggests a new molecule that inhibits Bcl-2 associated cancer/tumor regression.

Oncogene, 2008

Journal of Molecular Graphics & Modelling, 2010

Protein-protein interactions (PPIs) have emerged as important targets for pharmaceutical intervention because of their essential role in numerous physiological and pathological processes, but screening efforts using small-molecules have led to very low hit rates. Linear peptides could represent a quick and effective approach to discover initial PPI hits, particularly if they have inherent ability to adopt specific peptide secondary structures. Here, we address this hypothesis through a linear helical peptide library, composed of four sublibraries, which was designed by theoretical predictions of helicity (Agadir software). The 13-mer peptides of this collection fixes either a combination of three aromatic or two aromatic and one aliphatic residues on one face of the helix (Ac-SSEEX(5)ARNX(9)AAX(12)N-NH2), since these are structural features quite common at PPIs interfaces. The 81 designed peptides were conveniently synthesized by parallel solid-phase methodologies, and the tendency of some representative library components to adopt the intended secondary structure was corroborated through CD and NMR experiments. As proof of concept in the search for PPI modulators, the usefulness of this library was verified on the widely studied p53-MDM2 interaction and on the communication between VEGF and its receptor Flt-1, two PPIs for which a hydrophobic α-helix is essential for the interaction. We have demonstrated here that, in both cases, selected peptides from the library, containing the right hydrophobic sequence of the hot-spot in one of the protein partners, are able to interact with the complementary protein. Moreover, we have discover some new, quite potent inhibitors of the VEGF-Flt-1 interaction, just by replacing one of the aromatic residues of the initial F(5)Y(9)Y(12) peptide by W, in agreement with previous results on related antiangiogenic peptides. Finally, the HTS evaluation of the full collection on thermoTRPs has led to a few antagonists of TRPV1 and TRPA1 channels, which open new avenues on the way to innovative modulators of these channels.

Journal of Peptide Science, 2006

Journal of the American Chemical Society, 2011

Biochemical and Biophysical Research Communications, 2011

One of the most important problems in vaccine development consists in understanding receptor–ligand interactions between Class II Major Histocompatibility Complex molecules (MHC II) and antigenic peptides involved in inducing an appropriate immune response. In this study, we used X-ray crystallography structural data provided by the HLA-DRβ1*0301–CLIP peptide interaction to compare native non-immunogenic and specifically-modified immunogenic peptides derived from the malarial SALSA protein, by analyzing molecular electrostatic potential surfaces on the most important regions of the peptide binding groove (Pockets 1, 4, 6 and 9). Important differences were found on the electrostatic potential induced by these peptides, particularly in MHC II conserved residues: Qα9, Sα53, Nα62, Nα69, Yβ30, Yβ60, Wβ61, Qβ70, Kβ71 and Vβ86, the same ones involved in establishing hydrogen bonds between Class II molecule-peptide and the recognition by T cell receptor, it correlating well with the change in their immunological properties.The results clearly suggest that modifications done on the electrostatic potential of these amino acids could favor the induction of different immune responses and therefore, their identification could allow modifying peptides a priori and in silico, so as to render them into immunogenic and protection-inducers and hence suitable components of a chemically-synthesized, multi-antigenic, minimal subunit based vaccine.► We calculated the molecular electrostatic potentials (MEP) of MHC II pockets in the presence of different binding peptides. ► We examine changes in the MEP of MHC II produced by residue modifications on these peptides. ► We observed that MEP changes occur on critical residues of MHC II. ► These changes are correlated with the immunological activity of this peptides.

Designing drug delivery vehicles using cell-penetrating peptides is a hot area of research in the field of medicine. In the past, number of in silico methods have been developed for predicting cell-penetrating property of peptides containing natural residues. In this study, first time attempt has been made to predict cell-penetrating property of peptides containing natural and modified residues. The dataset used to develop prediction models, include structure and sequence of 732 chemically modified cell-penetrating peptides and an equal number of non-cell penetrating peptides. We analyzed the structure of both class of peptides and observed that positive charge groups, atoms, and residues are preferred in cell-penetrating peptides. In this study, models were developed to predict cell-penetrating peptides from its tertiary structure using a wide range of descriptors (2D, 3D descriptors, and fingerprints). Random Forest model developed by using PaDEL descriptors (combination of 2D, 3D, and fingerprints) achieved maximum accuracy of 95.10%, MCC of 0.90 and AUROC of 0.99 on the main dataset. The performance of model was also evaluated on validation/independent dataset which achieved AUROC of 0.98. In order to assist the scientific community, we have developed a web server "CellPPDMod" for predicting the cell-penetrating property of modified peptides (http:// webs.iiitd.edu.in/raghava/cellppdmod/).

Autoimmunity Reviews, 2011

Journal of Molecular Biology, 2001

Oncotarget, 2016

One of the hallmarks of cancer is a resistance to the induction of programmed cell death that is mediated by selection of cells with elevated expression of anti-apoptotic members of the BCL-2 family. To counter this resistance, new therapeutic agents known as BH3-mimetic small molecules are in development with the goal of antagonizing the function of anti-apoptotic molecules and promoting the induction of apoptosis. To facilitate the testing and modeling of BH3-mimetic agents, we have developed a powerful system for evaluation and screening of agents both in culture and in immune competent animal models by engineering mouse leukemic cells and re-programming them to be dependent on exogenously expressed human anti-apoptotic BCL-2 family members. Here we demonstrate that this panel of cell lines can determine the specificity of BH3-mimetics to individual anti-apoptotic BCL-2 family members (BCL-2, BCL-XL, BCL-W, BFL-1, and MCL-1), demonstrate whether cell death is due to the induction...