by EPS Pool of Writers
Why protein chemist chose phosphorus for protein bioconjugation?
In the last two decades, phosphorus-mediated chemoselective ligation reactions acquired the “gold” status for in vivo labeling of biomolecules. However, some drawbacks of phosphines, such as directing non-canonical amino acids (e.g. azides) as their reaction partners limits the scope of these…
Conjugates of Vancomycin and Cell-penetrating Peptides – New Weapons in the Armoury against Drug Resistant Bacteria
Staying one step ahead in the arms race against antibiotic resistant pathogenic bacteria is an ongoing challenge to the ingenuity of medicinal chemists. Multidrug-resistance has become a menacing threat to the antibiotic armoury used by clinicians to treat nosocomial and community-acquired…
Bioactive peptides from food protein degradation: Legume peptides
Animal and plant proteins, upon in vitro or in vivo digestion, have not only a nutritional role but are a rich source of bioactive peptides initially encrypted in the native protein sequences. The activities of these peptides range from antioxidant, antihypertensive or anti-obesity to antimicrobial…
Nature’s Shotgun Proteomics
The mammalian immune system, as part of its response to a viral infection, does something akin to a shotgun proteomics experiment. Viral proteins are digested, and the resulting peptides are presented—as a mixture—in a form that can be recognised by circulating T cells. In this article, I…
Thanatin – an Insect-derived Antimicrobial Peptide Active against Pathogenic Gram-negative Bacteria
Swiss researchers have recently revealed the mechanism by which the insect-derived antimicrobial peptide thanatin targets the intermembrane protein complex required for lipopolysaccharide (LPS) transport in Escherichia coli. Employing a series of elegant techniques directed at increasing levels of…
Peptide vaccines: the future of immunotherapy?
It is widely accepted that vaccines are valuable preparations for prevention against life-threatening diseases such as polio, measles and smallpox and their utilization led to control and/or eradication of aforementioned infectious diseases. Common drawbacks in classical vaccine formulations led to…
Targeted protein degradation as a new paradigm in drug discovery. Is there a role for peptides?
Despite the large number of new, therapeutically relevant proteins discovered in recent years, classical drug discovery strategies have not been particularly successful in finding suitable small-molecule modulators. Targeted protein degradation has raised considerable interest from…
Small Proteins, Big Data
The possibility that a subset of biological molecules has been overlooked, and is waiting to be discovered, is always intriguing. For small proteins (proteins of around 100 amino acid residues or fewer) there is evidence to suggest that this is indeed the case. In this article, I examine the…
Inhibition of Amyloidogenesis by Synthetic Enantiomeric Peptides
A synthetic peptide composed of alternating L- and D-amino acid residues has been recently shown to inhibit aggregation and reduce toxic effects in neuroblastoma cells, of the beta-amyloid peptide, Aβ, implicated in Alzheimer’s disease. In contrast, a “twin” peptide with the same sequence,…
New enzymatic approaches for the generation of peptide and protein conjugates
Enzymatic conjugation of peptides and their analogues to other peptides or proteins is considered to be an exciting field in protein chemistry. Besides Sortase A, Butelase and Transglutaminase, the field offers attractive possibilities with respect to its broad spectrum and simplicity.…
Peptides as invaluable tools in the search for innovative analgesics
Pain is a quite frequent complaint after injuries and accompanying different pathologies, which remains poorly treated for a number of patients. Pain involves extremely complex/interrelated series of signaling and modulatory pathways of the nervous system. Within them, the contribution to pain…
Thiol additive-free native chemical ligation
Native chemical ligation (NCL) commonly facilitates a peptide thioester with an N-terminal β-thiol peptide to form a native amide bond. Though many peptide thioester preparation strategies have been developed, it generally requires a large excess of exogenous thiol additives. Here I will discuss…
Epigallocatechin Gallate – Unravelling its Effect on Amyloid and Toxic Oligomers
Many medical disorders are associated with amyloid formation, Alzheimer disease (AD) and Parkinson disease (PD) being perhaps the most well-known. All such diseases have in common the pathological aggregation of a normally soluble polypeptide chain into a series of oligomeric intermediates and…
Figuring Out the Configuration
Peptides can sometimes exhibit unusual stereochemistry. Occasionally, for example, the usual l-amino acid building block might be substituted with its mirror-image counterpart. Such features can impact on function, but may be subtle enough to evade detection via routine methods. In this article,…
Bioorthogonal labeling of peptides and proteins-two recent examples
Site-specific introduction of distinct molecules into proteins and peptides is a challenging task. It becomes even more challenging if the labeling reaction has to be performed in living systems. How can we overcome undesired cross reactions with functional groups on proteins other than our target…
Where is the field of α-helix mimetics going?
Protein-protein interactions (PPI) are promiscuous in many biological pathways and their dysfunction is related to several pathologies. Therefore, PPI modulators are not only important probes to understand biological processes, but potential agents for pharmaceutical intervention. Taking into…
Pre-clinical Study Confirms Potential of Peptide Hydrogels As Localised Drug Delivery Vehicles
Hydrogel-forming peptides have the ability to self-assemble into nanofibres, which can further form 3D networks of entangled fibrous structures, essentially affording a scaffold-like architecture. Within minutes of adding these short peptides to water in appropriate proportions, a gel is formed,…
Non-Canonical Building Blocks Extend the Peptide Alphabet
The use of non-canonical amino-acid building blocks for peptide synthesis is a flexible way of introducing functionalities not normally found in biological systems. Two recent papers on this theme, both from Journal of Peptide Science, are discussed. In the first (Grob et al., 2017), methionine…
Native Chemical Ligation and Beyond: Recent Developments in Chemical Protein Synthesis
The total chemical synthesis of proteins has been one of the most challenging topics of organic chemistry in 20th century. The discovery of solid phase peptide synthesis (SPPS) in 1963 by R.B. Merrifield and the development of native chemical ligation (NCL) in 1994 by Kent and coworkers enabled the…
Will the discovery of cross-α amyloid-like fibrils herald a new definition of amyloid?
In microorganisms, functional amyloid is often involved in virulence mechanisms. Staphylococcus aureus secretes a 22-residue phenol-soluble modulin α3 (PSMα3) peptide, capable of forming elongated fibrils, with the appearance and staining properties typical of amyloid. Researchers working to…
