Browse
Submit Data
Databases
API
Help

Dataset Information

12 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Synthetic Control of Tertiary Helical Structures in Short Peptides.

ABSTRACT: Helical secondary and tertiary motifs are commonly observed as binding epitopes in natural and engineered protein scaffolds. While several strategies have been described to constrain ?-helices or reproduce their binding attributes in synthetic mimics, general strategies to mimic tertiary helical motifs remain in their infancy. We recently described a synthetic strategy to develop helical dimers ( J. Am. Chem. Soc. 2015, 137, 11618-11621). We found that replacement of an interhelical salt bridge with a covalent bond can stabilize antiparallel motifs in short sequences. Here we show that the approach can be generalized to obtain antiparallel and parallel dimers as well as trimer motifs. Helical stabilization requires judiciously designed cross-linkers as well as optimal interhelical hydrophobic packing. We anticipate that these mimics would afford new classes of modulators of biological function.

SUBMITTER: Wuo MG

PROVIDER: S-EPMC7768809 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Synthetic Control of Tertiary Helical Structures in Short Peptides.

Wuo Michael G MG Hong Seong Ho SH Singh Arunima A Arora Paramjit S PS

Journal of the American Chemical Society 20181114 47

Helical secondary and tertiary motifs are commonly observed as binding epitopes in natural and engineered protein scaffolds. While several strategies have been described to constrain α-helices or reproduce their binding attributes in synthetic mimics, general strategies to mimic tertiary helical motifs remain in their infancy. We recently described a synthetic strategy to develop helical dimers ( J. Am. Chem. Soc. 2015, 137, 11618-11621). We found that replacement of an interhelical salt bridge ...[more]

PMID: 30395711

Similar Datasets

Incorporating Polarizability of Backbone Hydrogen Bonds Improved Folding of Short ?-Helical Peptides.

Project description:Reliability of force fields is an essential aspect of protein-folding simulation. In this work, we introduced a newly developed on-the-fly charge-updating scheme called the polarized structure-specific backbone charge (PSBC) model. The PSBC model was designed with the purpose of building the polarizability of backbone hydrogen bonds into the force field by updating the partial charges of backbone hydrogen-bond donor and acceptor atoms during folding simulation. This implementation was intended to mimic the heterogeneity of the protein surrounding during folding. Multiple single-trajectory molecular dynamics simulations were performed to fold a polyalanine peptide, namely ER (Ac-A(EAAAR)3A-NH2), using both polarizable (PSBC) and nonpolarizable (Amber03) force fields. Through the PSBC model, ER was folded into a helical peptide with helix content that agrees well with experiments. Comparison between simulations performed using the aforementioned force fields demonstrably showed the importance of electrostatic polarization effect in the folding of the short ?-helical peptide. The PSBC model was further validated by folding two other short peptides with different helicities.

| S-EPMC6895711 | biostudies-literature

Short oligoalanine helical peptides for supramolecular nanopore assembly and protein cytosolic delivery.

Project description:In this work we report a rational design strategy for the identification of new peptide prototypes for the non-disruptive supramolecular permeation of membranes and the transport of different macromolecular giant cargos. The approach targets a maximal enhancement of helicity in the presence of membranes with sequences bearing the minimal number of cationic and hydrophobic moieties. The here reported folding enhancement in membranes allowed the selective non-lytic translocation of different macromolecular cargos including giant proteins. The transport of different high molecular weight polymers and functional proteins was demonstrated in vesicles and in cells with excellent efficiency and optimal viability. As a proof of concept, functional monoclonal antibodies were transported for the first time into different cell lines and cornea tissues by exploiting the helical control of a short peptide sequence. This work introduces a rational design strategy that can be employed to minimize the number of charges and hydrophobic residues of short peptide carriers to achieve non-destructive transient membrane permeation and transport of different macromolecules.

| S-EPMC8341679 | biostudies-literature

Orthogonal Halogen-Bonding-Driven 3D Supramolecular Assembly of Right-Handed Synthetic Helical Peptides.

Project description:Peptide-mediated self-assembly is a prevalent method for creating highly ordered supramolecular architectures. Herein, we report the first example of orthogonal C-X???X-C/C-X???? halogen bonding and hydrogen bonding driven crystalline architectures based on synthetic helical peptides bearing hybrids of l-sulfono-?-AApeptides and natural amino acids. The combination of halogen bonding, intra-/intermolecular hydrogen bonding, and intermolecular hydrophobic interactions enabled novel 3D supramolecular assembly. The orthogonal halogen bonding in the supramolecular architecture exerts a novel mechanism for the self-assembly of synthetic peptide foldamers and gives new insights into molecular recognition, supramolecular design, and rational design of biomimetic structures.

| S-EPMC6534470 | biostudies-literature

Aromatic interactions promote self-association of collagen triple-helical peptides to higher-order structures.

Project description:Aromatic residues are relatively rare within the collagen triple helix, but they appear to play a specialized role in higher-order structure and function. The role of aromatic amino acids in the self-assembly of triple-helical peptides was investigated in terms of the kinetics of self-association, the nature of aggregated species formed, and the ability of these species to activate platelet aggregation. The presence of aromatic residues on both ends of a type IV collagen model peptide is observed to greatly accelerate the kinetics of self-association, decreasing the lag time and leading to insoluble, well-defined linear fibrils as well as small soluble aggregates. Both macroscopic visible aggregates and small multimolecular complexes in solution are capable of inducing platelet aggregation through the glycoprotein VI receptor on platelets. Proline-aromatic CH...pi interactions are often observed within globular proteins and in protein complexes, and examination of molecular packing in the crystal structure of the integrin binding collagen peptide shows Phe interacts with Pro/Hyp in a neighboring triple-helical molecule. An intermolecular interaction between aromatic amino acids and imino acids within the triple helix is also supported by the observed inhibitory effect of isolated Phe amino acids on the self-association of (Pro-Hyp-Gly)(10). Given the high fraction of Pro and Hyp residues on the surface of collagen molecules, it is likely that imino acid-aromatic CH...pi interactions are important in formation of higher-order structure. We suggest that the catalysis of type I collagen fibrillogenesis by nonhelical telopeptides is due to specific intermolecular CH...pi interactions between aromatic residues in the telopeptides and Pro/Hyp residues within the triple helix.

| S-EPMC2784932 | biostudies-literature

Functional importance of short-range binding and long-range solvent interactions in helical antifreeze peptides.

Project description:Short-range ice binding and long-range solvent perturbation both have been implicated in the activity of antifreeze proteins and antifreeze glycoproteins. We study these two mechanisms for activity of winter flounder antifreeze peptide. Four mutants are characterized by freezing point hysteresis (activity), circular dichroism (secondary structure), Förster resonance energy transfer (end-to-end rigidity), molecular dynamics simulation (structure), and terahertz spectroscopy (long-range solvent perturbation). Our results show that the short-range model is sufficient to explain the activity of our mutants, but the long-range model provides a necessary condition for activity: the most active peptides in our data set all have an extended dynamical hydration shell. It appears that antifreeze proteins and antifreeze glycoproteins have reached different evolutionary solutions to the antifreeze problem, utilizing either a few precisely positioned OH groups or a large quantity of OH groups for ice binding, assisted by long-range solvent perturbation.

| S-EPMC3400764 | biostudies-literature

Compositional control of higher order assembly using synthetic collagen peptides.

Project description:We present the case of a two-component collagen peptide hydrogel that self-assembles through noncovalent electrostatic interactions. Natural collagen materials, such as those of connective tissue or the basement membrane, assemble in a hierarchic fashion. Similarly, the synthetic peptides presented here proceed from monomer to trimer to fiber and, finally, to a hydrogel. By varying stoichiometry and concentration, we are able to dissect the stages of higher order assembly. Insight gained from this study will improve the molecular design of biomimetic materials.

| S-EPMC3443862 | biostudies-literature

Targeting MDMD and PD1 in Tumors With Tertiary Lymphoid Structures

Project description:Phase II, multicenter, open-label, multi-cohort proof-of-concept study designed to evaluate the safety and efficacy of Ezabenlimab combined with BI 907828 in patients with unresectable, locally advanced or metastatic solid tumors.

| 109483 | ecrin-mdr-crc

High specific selectivity and Membrane-Active Mechanism of the synthetic centrosymmetric ?-helical peptides with Gly-Gly pairs.

Project description:We used a template-assisted approach to develop synthetic antimicrobial peptides, which differ from naturally occurring antimicrobial peptides that can compromise host natural defenses. Previous researches have demonstrated that symmetrical distribution patterns of amino acids contribute to the antimicrobial activity of natural peptides. However, there is little research describing such design ideas for synthetic ?-helical peptides. Therefore, here, we established a centrosymmetric ?-helical sequence template (y?+?hhh?+?y)n (h, hydrophobic amino acid; +, cationic amino acid; y, Gly or hydrophobic amino acid), which contributed to amphipathicity, and a series of centrosymmetric peptides was designed with pairs of small amino acids (Ala and Gly), which were utilized to modulate the biological activity. The centrosymmetric peptides with 3 repeat units exhibited strong antimicrobial activity; in particular, the Gly-rich centrosymmetric peptide GG3 showed stronger selectivity for gram-negative bacteria without hemolysis. Furthermore, beyond our expectation, fluorescence spectroscopy and electron microscopy analyses indicated that the GG3, which possessed poor ?-helix conformation, dramatically exhibited marked membrane destruction via inducing bacterial membrane permeabilization, pore formation and disruption, even bound DNA to further exert antimicrobial activity. Collectively, the Gly-rich centrosymmetric peptide GG3 was an ideal candidate for commercialization as a clinical therapeutic to treat gram-negative bacterial infections.

| S-EPMC4632126 | biostudies-literature

Energetic characterization of short helical polyalanine peptides in water: analysis of 13C=O chemical shift data.

Project description:Measured at 2 degrees C in water, NMR chemical shifts of (13)C=O labeled central alanine residues of peptides W-Lys(5)-(t)L(3)-Ala(n)-(t)L(3)-Lys(5)NH(2), n = 9, 11, 13, 15, 19 and W-Lys(5)-(t)L(3)-a-Ala(n)-A-Inp-(t)L(2)-Lys(5)NH(2) (a = D-Ala; (t)L = tert-leucine; Inp = 4-carboxypiperidine) are used to assign jt(L) and ct(L), the N- and C-terminal (t)L capping parameters and length-dependent values for w(Ala)(n), the alanine helical propensity for Ala(n) peptides. These parameters allow Lifson-Roig characterization of the stabilities of Ala(n)() helices in water. To facilitate chemical shift characterization, different (13)C/(12)C ratios are incorporated into specific Ala sites to code up to six residue sites per peptide. Large left/right chemical shift anisotropies are intrinsic to helical polyalanines, and a correcting L-R-based model is introduced. Capping parameters jt(L) = ct(L) lie in the range of 0.3 to 0.5; the (t)L residues are thus moderately helix-destabilizing. For helical conformations of lengths shorter than eight residues, assigned values for w(Ala) approach 1.0 but increase monotonically with length to a value of 1.59 for w(Ala)(19).

| S-EPMC1560102 | biostudies-literature

Inhibition of FOXP3 by Stapled Alpha-Helical Peptides Dampens Regulatory T Cell Function

Project description:Despite continuing advances in the development of novel cellular-, antibody-, and chemotherapeutic-based strategies to enhance immune reactivity, the presence of regulatory T cells (Tregs) remains a complicating factor to their clinical efficacy. To overcome dosing limitations and off-target effects from antibody-based Treg deletional strategies, we investigated the ability of hydrocarbon stapled alpha-helical (SAH) peptides to target FOXP3, the master transcription factor regulator of Treg development, maintenance, and suppressive function. Using the crystal structure of the FOXP3 homodimer as a guide, we developed SAHs in the likeness of a portion of the native FOXP3 antiparallel coiled-coil homodimerization domain (SAH-FOXP3) to block this key FOXP3 protein-protein interaction (PPI) through molecular mimicry. We show that lead SAH-FOXP3s bind FOXP3, are cell permeable, non-toxic to T cells, induce dose-dependent transcript and protein level alterations of FOXP3 target genes, impede Treg function, and lead to Treg gene expression changes in vivo consistent with Foxp3 dysfunction.

2022-09-29 | GSE201116 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data