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A de novo designed class of peptide‐based fluoropolymers composed of fluorinated aliphatic amino acids as main components is reported. Structural characterization provided insights into fluorine‐induced alterations on β‐strand to α‐helix transition upon an increase in SDS content and revealed the unique formation of PPII structures for trifluorinated fluoropeptides. A combination of circular dichroism, fluorescence‐based leaking assays and surface enhanced infrared absorption spectroscopy served to examine the insertion and folding processes into unilamellar vesicles. While partitioning into lipid bilayers, the degree of fluorination conducts a decrease in α‐helical content. Furthermore, this study comprises a report on the proteolytic stability of peptides exclusively built up by fluorinated amino acids and proved all sequences to be enzymatically degradable despite the degree of fluorination. Herein presented fluoropeptides as well as the distinctive properties of these artificial and polyfluorinated foldamers with enzyme‐degradable features will play a crucial role in the future development of fluorinated peptide‐based biomaterials. [ABSTRACT FROM AUTHOR]

Proteolytic enzymes are often strongly affected by redox reactions, free radicals, oxidation, or oxidative stress. The 20S Proteasome and the Immuno-Proteasome are examples of major intracellular proteases whose concentration, transcription, translation, and proteolytic activity are all subject to redox regulation. Proteasomes are essential in maintaining overall protein homeostasis (or proteostasis), and their dysregulation results in detrimental phenotypes associated with various pathologies, including several common age-related diseases. Many studies have used Western blots to assess redox changes in Proteasome protein levels or RT-PCR to study RNA transcript levels, but actual measurements of proteolytic activity are far less common. Since each intact protein substrate exhibits a different proteolytic profile when incubated with proteasome or Immuno-Proteasome [± activators such as 19S or 11S (also called PA28)] and these proteolytic profiles are drastically altered if the protein substrate is denatured, for example by oxidation, heat, acetylation, or methylation. In an attempt to standardize proteasomal activity measurements small fluorogenic protein/peptide substrates were developed to test the three proteolytically active sites of the Proteasome and Immuno-Proteasome: trypsin-like, chymotrypsin-like, and caspase-like activities. Despite extensive use of fluorogenic peptide substrates to measure proteasome activity, there is an absence of a standardized set of best practices. In this study we analyze different parameters, such as sample concentration, AMC conjugated substrate concentration, duration of assay, and frequency of measurements, and examine how they impact the determination of Proteasome and Immuno-Proteasome activities using fluorogenic peptide substrates. Image 1 • Proteases like Proteasome & Immunoproteasome minimize accumulation of oxidized proteins. • Proteases like Proteasome and Immunoproteasome are subject to redox regulation. • Proteasome & Immunoproteasome activities can be measured with fluorogenic peptides. • Fluoropeptide concentration, assay duration, and measurement frequency must be optimized. • Specific activities should be averaged during constant maximal fluorescence plateau. [ABSTRACT FROM AUTHOR]

Background FP-01.1 is a novel synthetic influenza A vaccine consisting of six fluorocarbon-modified 35-mer peptides that encapsulate multiple CD4+ and CD8+ T-cell epitopes and is designed to induce an immune response across a broad population. Methods FP-01.1 was evaluated for safety and immunogenicity in a randomised, double-blind, placebo-controlled, dose-escalation, phase I clinical study in healthy adult volunteers ( n = 49). IFNγ ELISpot assays and multicolour flow cytometry were used to characterise the immune response. Results FP-01.1 was safe and well tolerated at all doses tested with a similar adverse event profile in actively vaccinated subjects compared with controls. Maximum immunogenicity was in the 150 μg/peptide dose group where a robust response (243 spots/million PBMC) was demonstrated in 75% subjects compared with 0% in placebo controls. All six peptides were immunogenic. FP-01.1 induced dual CD4+ and CD8+ T cell responses and vaccine-specific T cells cross-recognise divergent influenza strains. Conclusions This first-in-human study showed that FP-01.1 has an acceptable safety and tolerability profile and generated robust anti-viral T cell responses in a high proportion of subjects tested. The results support the further clinical testing of FP-01.1 prior to clinical, proof-of-concept, live viral challenge studies. [ABSTRACT FROM AUTHOR]