Origin of Proteolytic Stability of Peptide-Brush Polymers as Globular Proteomimetics

Antimicrobial peptides (AMPs) present a promising scaffold for the development of potent antimicrobial agents. Substitution of tryptophan by non-natural amino acid Azulenyl-Alanine (AzAla) would allow studying the mechanism of action of AMPs by using unique properties of this amino acid, such as ability to be excited separately from tryptophan in a multi-Trp AMPs and environmental insensitivity. In this work, we investigate the effect of Trp→AzAla substitution in antimicrobial peptide buCATHL4B (contains three Trp side chains). We found that antimicrobial and bactericidal activity of the original peptide was preserved, while cytocompatibility with human cells and proteolytic stability was improved. We envision that AzAla will find applications as a tool for studies of the mechanism of action of AMPs. In addition, incorporation of this non-natural amino acid into AMP sequences could enhance their application properties.

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Controlled Synthesis of Well-Defined Semiconducting Brush Polymers

Macromolecular Chemistry and Physics ◽

10.1002/macp.201500213 ◽

2015 ◽

Vol 217 (3) ◽

pp. 403-413 ◽

Cited By ~ 8

Author(s):

Dean van As ◽

Jegadesan Subbiah ◽

David J. Jones ◽

Wallace W. H. Wong

Keyword(s):

Controlled Synthesis ◽

Brush Polymers

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Methods to study the structure of misfolded protein states in systemic amyloidosis

Biochemical Society Transactions ◽

10.1042/bst20201022 ◽

2021 ◽

Vol 49 (2) ◽

pp. 977-985

Author(s):

Marcus Fändrich ◽

Matthias Schmidt

Keyword(s):

Protein Misfolding ◽

Amyloid Fibrils ◽

Ex Vivo ◽

Systemic Amyloidosis ◽

Structural Basis ◽

Amyloid A ◽

Serum Amyloid A Protein ◽

Proteolytic Stability

Systemic amyloidosis is defined as a protein misfolding disease in which the amyloid is not necessarily deposited within the same organ that produces the fibril precursor protein. There are different types of systemic amyloidosis, depending on the protein constructing the fibrils. This review will focus on recent advances made in the understanding of the structural basis of three major forms of systemic amyloidosis: systemic AA, AL and ATTR amyloidosis. The three diseases arise from the misfolding of serum amyloid A protein, immunoglobulin light chains or transthyretin. The presented advances in understanding were enabled by recent progress in the methodology available to study amyloid structures and protein misfolding, in particular concerning cryo-electron microscopy (cryo-EM) and nuclear magnetic resonance (NMR) spectroscopy. An important observation made with these techniques is that the structures of previously described in vitro formed amyloid fibrils did not correlate with the structures of amyloid fibrils extracted from diseased tissue, and that in vitro fibrils were typically more protease sensitive. It is thus possible that ex vivo fibrils were selected in vivo by their proteolytic stability.

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Synthesis, Proteolytic Stability, and In vitro Evaluation of DOTA Conjugated p160 Peptide Based Radioconjugates: [177Lu]Lu-DOTA-p160

Organic & Biomolecular Chemistry ◽

10.1039/d1ob01812d ◽

2021 ◽

Author(s):

Jasleen Kaur ◽

Karim Arroub ◽

Alexander Drzezga ◽

Klaus Schomaecker ◽

Sanjay Mathur

Keyword(s):

Biological Evaluation ◽

In Vitro Evaluation ◽

Enzymatic Stability ◽

Proteolytic Stability ◽

In Vitro Stability

In this work, we describe the synthesis, in-vitro stability, and preliminary biological evaluation of [177Lu]Lu-DOTA-p160 peptide-based radiopharmaceuticals. Our findings highlight that all DOTA-p160-peptide radioconjugates exhibit favorable proteolytic and enzymatic stability...

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Antiseptic 9-Meric Peptide with Potency against Carbapenem-Resistant Acinetobacter baumannii Infection

International Journal of Molecular Sciences ◽

10.3390/ijms222212520 ◽

2021 ◽

Vol 22 (22) ◽

pp. 12520

Author(s):

Manigandan Krishnan ◽

Joonhyeok Choi ◽

Ahjin Jang ◽

Young Kyung Yoon ◽

Yangmee Kim

Keyword(s):

Membrane Integrity ◽

Systemic Infection ◽

Organ Damage ◽

Immunosuppressive Agent ◽

Multiple Organ ◽

Raw 264.7 Cells ◽

Peptide Antibiotics ◽

Gram Negative ◽

Carbapenem Resistant ◽

Proteolytic Stability

Carbapenem-resistant A. baumannii (CRAB) infection can cause acute host reactions that lead to high-fatality sepsis, making it important to develop new therapeutic options. Previously, we developed a short 9-meric peptide, Pro9-3D, with significant antibacterial and cytotoxic effects. In this study, we attempted to produce safer peptide antibiotics against CRAB by reversing the parent sequence to generate R-Pro9-3 and R-Pro9-3D. Among the tested peptides, R-Pro9-3D had the most rapid and effective antibacterial activity against Gram-negative bacteria, particularly clinical CRAB isolates. Analyses of antimicrobial mechanisms based on lipopolysaccharide (LPS)-neutralization, LPS binding, and membrane depolarization, as well as SEM ultrastructural investigations, revealed that R-Pro9-3D binds strongly to LPS and impairs the membrane integrity of CRAB by effectively permeabilizing its outer membrane. R-Pro9-3D was also less cytotoxic and had better proteolytic stability than Pro9-3D and killed biofilm forming CRAB. As an LPS-neutralizing peptide, R-Pro9-3D effectively reduced LPS-induced pro-inflammatory cytokine levels in RAW 264.7 cells. The antiseptic abilities of R-Pro9-3D were also investigated using a mouse model of CRAB-induced sepsis, which revealed that R-Pro9-3D reduced multiple organ damage and attenuated systemic infection by acting as an antibacterial and immunosuppressive agent. Thus, R-Pro9-3D displays potential as a novel antiseptic peptide for treating Gram-negative CRAB infections.

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Cryo-EM demonstrates the in vitro proliferation of an ex vivo amyloid fibril morphology by seeding

Nature Communications ◽

10.1038/s41467-021-27688-5 ◽

2022 ◽

Vol 13 (1) ◽

Author(s):

Thomas Heerde ◽

Matthies Rennegarbe ◽

Alexander Biedermann ◽

Dilan Savran ◽

Peter B. Pfeiffer ◽

...

Keyword(s):

Amyloid Fibrils ◽

Ex Vivo ◽

Proteinase K ◽

Seed Structure ◽

In Vitro Proliferation ◽

Amyloid A ◽

Fibril Structure ◽

Proteolytic Stability ◽

Fibril Morphology

AbstractSeveral studies showed that seeding of solutions of monomeric fibril proteins with ex vivo amyloid fibrils accelerated the kinetics of fibril formation in vitro but did not necessarily replicate the seed structure. In this research we use cryo-electron microscopy and other methods to analyze the ability of serum amyloid A (SAA)1.1-derived amyloid fibrils, purified from systemic AA amyloidosis tissue, to seed solutions of recombinant SAA1.1 protein. We show that 98% of the seeded fibrils remodel the full fibril structure of the main ex vivo fibril morphology, which we used for seeding, while they are notably different from unseeded in vitro fibrils. The seeded fibrils show a similar proteinase K resistance as ex vivo fibrils and are substantially more stable to proteolytic digestion than unseeded in vitro fibrils. Our data support the view that the fibril morphology contributes to determining proteolytic stability and that pathogenic amyloid fibrils arise from proteolytic selection.

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Interfacial Peptides as Affinity Modulating Agents of Protein-Protein Interactions

Biomolecules ◽

10.3390/biom12010106 ◽

2022 ◽

Vol 12 (1) ◽

pp. 106

Author(s):

Pavel V. Ershov ◽

Yuri V. Mezentsev ◽

Alexis S. Ivanov

Keyword(s):

Protein Interactions ◽

Targeted Delivery ◽

Protein Complexes ◽

Protein Protein Interactions ◽

Good Efficiency ◽

Cellular Targets ◽

Proteolytic Stability ◽

Clinically Significant

The identification of disease-related protein-protein interactions (PPIs) creates objective conditions for their pharmacological modulation. The contact area (interfaces) of the vast majority of PPIs has some features, such as geometrical and biochemical complementarities, “hot spots”, as well as an extremely low mutation rate that give us key knowledge to influence these PPIs. Exogenous regulation of PPIs is aimed at both inhibiting the assembly and/or destabilization of protein complexes. Often, the design of such modulators is associated with some specific problems in targeted delivery, cell penetration and proteolytic stability, as well as selective binding to cellular targets. Recent progress in interfacial peptide design has been achieved in solving all these difficulties and has provided a good efficiency in preclinical models (in vitro and in vivo). The most promising peptide-containing therapeutic formulations are under investigation in clinical trials. In this review, we update the current state-of-the-art in the field of interfacial peptides as potent modulators of a number of disease-related PPIs. Over the past years, the scientific interest has been focused on following clinically significant heterodimeric PPIs MDM2/p53, PD-1/PD-L1, HIF/HIF, NRF2/KEAP1, RbAp48/MTA1, HSP90/CDC37, BIRC5/CRM1, BIRC5/XIAP, YAP/TAZ–TEAD, TWEAK/FN14, Bcl-2/Bax, YY1/AKT, CD40/CD40L and MINT2/APP.

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Carbamate group as structural motif in drugs: a review of carbamate derivatives used as therapeutic agents

Archives of Industrial Hygiene and Toxicology ◽

10.2478/aiht-2020-71-3466 ◽

2020 ◽

Vol 71 (4) ◽

pp. 285-299

Author(s):

Ana Matošević ◽

Anita Bosak

Keyword(s):

Peptide Bond ◽

Structural Motif ◽

Target Interaction ◽

Modern Drug ◽

First Pass Metabolism ◽

First Pass ◽

Functional Part ◽

Proteolytic Stability ◽

Carbamate Group ◽

Pass Metabolism

AbstractDue to their very good chemical and proteolytic stability, ability to penetrate cell membranes, and resemblance to a peptide bond, carbamate derivatives have received much attention in recent years and got an important role in modern drug discovery and medicinal chemistry. Today, carbamates make structural and/or functional part of many drugs and prodrugs approved and marketed for the treatment of various diseases such as cancer, epilepsy, hepatitis C, HIV infection, and Alzheimer’s disease. In drugs they can play a role in drug-target interaction or improve the biological activity of parent molecules. In prodrugs they are mainly used to delay first-pass metabolism and enhance the bioavailability and effectiveness of compounds. This brief review takes a look at the properties and use of carbamates in various fields of medicine and provides quick insights into the mechanisms of action for some of them.

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