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1. Turn-folding in fluorescent anthracene-substituted cyclopenta[d]isoxazoline short peptides

Author:
Leusciatti, Marco; Mannucci, Barbara; Recca, Teresa; Quadrelli, Paolo
Source:
RSC advances 2021 v.11 no.32 pp. 19551-19559
ISSN:
2046-2069
Subject:
peptides,   etc   ; amino acids; fluorescence;     Show all 3 Subjects
Abstract:
... Cyclopenta[d]isoxazoline aminols were used for the synthesis of β-turn mimics. The peptide chain choice ascertained the influence of their structural features on the applicability/reliability/robustness of these scaffolds as β-turn inducers and their limitations. The amino acid selection as well as steric demands can favor or disfavor the structure folding and the correct design of the peptide cha ...
DOI:
10.1039/d1ra03685h

2. Visualization of third-level information in latent fingerprints by a new fluorogenic l-tyrosine analogue

Author:
Singh, Harminder; Verma, Sandeep
Source:
Chemical communications 2021 v.57 no.43 pp. 5290-5293
ISSN:
1364-548X
Subject:
peptides,   etc   ; fluorescence; tyrosine;     Show all 3 Subjects
Abstract:
... Incorporation of fluorescent α-amino acids in peptide/protein sequences, at desired positions, is eminently useful for non-invasive detection of cellular events, without impacting their native properties. As an extension to such an approach, we describe the design of two stable, fluorescent l-tyrosine analogs, FHBY and BHBY, exhibiting photophysical properties associated with the AIE-coupled ESIPT ...
DOI:
10.1039/d1cc01910d

3. Late Stage Phosphotyrosine Mimetic Functionalization of Peptides Employing Metallaphotoredox Catalysis

Author:
Chen, Hao; Mao, Runyu; Brzozowski, Martin; Nguyen, Nghi H.; Sleebs, Brad E.
Source:
Organic letters 2021 v.23 no.11 pp. 4244-4249
ISSN:
1523-7052
Subject:
peptides,   etc   ; catalytic activity; phenylalanine;     Show all 3 Subjects
Abstract:
... Access to phosphotyrosine (pTyr) mimetics requires multistep syntheses, and therefore late stage incorporation of these mimetics into peptides is not feasible. Here, we develop and employ metallaphotoredox catalysis using 4-halogenated phenylalanine to afford a variety of protected pTyr mimetics in one step. This methodology was shown to be tolerant of common protecting groups and applicable to th ...
DOI:
10.1021/acs.orglett.1c01200

4. Delocalization-Assisted Transport through Nucleic Acids in Molecular Junctions

Author:
Valdiviezo, Jesús; Clever, Caleb; Beall, Edward; Pearse, Alexander; Bae, Yookyung; Zhang, Peng; Achim, Catalina; Beratan, David N.; Waldeck, David H.
Source:
Biochemistry 2021 v.60 no.17 pp. 1368-1378
ISSN:
1520-4995
Subject:
peptides,   etc   ; DNA; DNA repair;     Show all 3 Subjects
Abstract:
... The flow of charge through molecules is central to the function of supramolecular machines, and charge transport in nucleic acids is implicated in molecular signaling and DNA repair. We examine the transport of electrons through nucleic acids to understand the interplay of resonant and nonresonant charge carrier transport mechanisms. This study reports STM break junction measurements of peptide nu ...
DOI:
10.1021/acs.biochem.1c00072

5. Amyloid-like Prep1 peptides exhibit reversible blue-green-red fluorescence in vitro and in living cells

Author:
Monti, Alessandra; Bruckmann, Chiara; Blasi, Francesco; Ruvo, Menotti; Vitagliano, Luigi; Doti, Nunzianna
Source:
Chemical communications 2021 v.57 no.30 pp. 3720-3723
ISSN:
1364-548X
Subject:
peptides,   etc   ; amyloid; fluorescence; pH;     Show all 4 Subjects
Abstract:
... PREP1-based peptides form amyloid-like aggregates endowed with an intrinsic blue-green-red fluorescence with an unusual sharp maximum at 520 nm upon excitation with visible light under physiological conditions. The peptide PREP1[117-132], whose sequence does not contain aromatic residues, presents a pH-dependent and reversible fluorescence, in line with its structural transition from β-sheet rich ...
DOI:
10.1039/d1cc01145f

6. PdCl₂/DMSO-Catalyzed Thiol–Disulfide Exchange: Synthesis of Unsymmetrical Disulfide

Author:
Guo, Jimin; Zha, Jianjian; Zhang, Tao; Ding, Chang-Hua; Tan, Qitao; Xu, Bin
Source:
Organic letters 2021 v.23 no.8 pp. 3167-3172
ISSN:
1523-7052
Subject:
peptides,   etc   ; disulfides; drugs; thiols;     Show all 4 Subjects
Abstract:
... Unsymmetrical disulfides have been effectively prepared through thiol exchange with symmetrical disulfides employing a simple PdCl₂/DMSO catalytic system. The given method features excellent functional group tolerance, a broad substrate scope, and operational simplicity. This reaction is especially useful for late-stage functionalization of bioactive scaffolds such as peptides and pharmaceuticals. ...
DOI:
10.1021/acs.orglett.1c00858

7. A reactive peptide interface for site-selective cysteine bioconjugation

Author:
Tuang, Suan; Dieppa-Matos, Diomedes; Zhang, Chi; Shugrue, Christopher R.; Dai, Peng; Loas, Andrei; Pentelute, Bradley L.
Source:
Chemical communications 2021 v.57 no.26 pp. 3227-3230
ISSN:
1364-548X
Subject:
peptides,   etc   ; chemical bonding; cysteine;     Show all 3 Subjects
Abstract:
... We report aqueous, site-selective modification of proteins using a reactive peptide interface comprising a nine-residue sequence. This interface is the fastest (second-order rate constant of 152 M⁻¹ s⁻¹) catalyst-free, cysteine-based method for modifying proteins available to date, and enables near-quantitative labeling of antibodies in cell lysate. ...
DOI:
10.1039/d1cc00095k

8. Synthesis of redox-active fluorinated 5-hydroxytryptophans as molecular reporters for biological electron transfer

Author:
Ohler, Amanda; Long, Hanna; Ohgo, Kei; Tyson, Kristin; Murray, David; Davis, Amanda; Whittington, Chris; Hvastkovs, Eli G.; Duffy, Liam; Haddy, Alice; Sargent, Andrew L.; Allen, William E.; Offenbacher, Adam R.
Source:
Chemical communications 2021 v.57 no.25 pp. 3107-3110
ISSN:
1364-548X
Subject:
peptides,   etc   ; electron transfer; spectroscopy;     Show all 3 Subjects
Abstract:
... Fluorinated 5-hydroxytryptophans (Fₙ-5HOWs) were synthesized in gram scale quantities and incorporated into a β-hairpin peptide and the protein azurin. The redox-active Fₙ-5HOWs exhibit unique radical spectroscopic signatures that expand the function of 5HOW as probes for biological electron transfer. ...
DOI:
10.1039/d1cc00187f

9. Cobalt-Catalyzed C(sp²)–H Carbonylation of Amino Acids Using Picolinamide as a Traceless Directing Group

Author:
Lukasevics, Lukass; Cizikovs, Aleksandrs; Grigorjeva, Liene
Source:
Organic letters 2021 v.23 no.7 pp. 2748-2753
ISSN:
1523-7052
Subject:
peptides,   etc   ; catalysts; cobalt; phenylalanine;     Show all 4 Subjects
Abstract:
... Herein we report an efficient protocol for the C(sp²)–H carbonylation of amino acid derivatives based on an inexpensive cobalt(II) salt catalyst. Carbonylation was accomplished using picolinamide as a traceless directing group, CO (1 atm) as the carbonyl source, and Co(dpm)₂ as the catalyst. A broad range of phenylalanine derivatives bearing diverse functional groups were tolerated. Moreover, the ...
DOI:
10.1021/acs.orglett.1c00660

10. GALA peptide improves the potency of nanobody–drug conjugates by lipid-induced helix formation

Author:
Chen, Ya Jie; Deng, Qi Wen; Wang, Li; Guo, Xiao Chun; Yang, Jian Yuan; Li, Ting; Xu, Zhengshuang; Lee, Hon Cheung; Zhao, Yong Juan
Source:
Chemical communications 2021 v.57 no.12 pp. 1434-1437
ISSN:
1364-548X
Subject:
peptides,   etc   ; cytotoxicity; endocytosis; surfactants;     Show all 4 Subjects
Abstract:
... A novel nanobody–drug conjugate (NDC) was constructed by incorporating an amphipathic peptide, GALA, which improved the cytotoxicity by one to two orders of magnitude. Mechanistic studies demonstrate that tethering to lipids induces GALA to form a helix, which dramatically enhances endocytosis. Our work provides a general strategy not only for improving the anti-cancer efficacy of protein-drug con ...
DOI:
10.1039/d0cc07706b

11. C-Terminal lactamization of peptides

Author:
Fischer, Niklas H.; Nielsen, Daniel S.; Palmer, Daniel; Meldal, Morten; Diness, Frederik
Source:
Chemical communications 2021 v.57 no.7 pp. 895-898
ISSN:
1364-548X
Subject:
peptides,   etc   ; bioactive properties; lactams;     Show all 3 Subjects
Abstract:
... Solid-phase synthesis of peptides (SPPS) with release through formation of C-terminal γ-, δ-, or ε-lactams is presented. The natural products ciliatamide A and C were synthesized in up to 90% yield. Peptides carrying C-terminal lactams were shown to possess increased bio-stability and comparable biological activity as compared to the parent non-lactamized peptide amides. ...
DOI:
10.1039/d0cc06018f

12. Antifouling biosensors for reliable protein quantification in serum based on designed all-in-one branched peptides

Author:
Liu, Nianzu; Ma, Yihui; Han, Rui; Lv, Shaoping; Wang, Peipei; Luo, Xiliang
Source:
Chemical communications 2021 v.57 no.6 pp. 777-780
ISSN:
1364-548X
Subject:
peptides,   etc   ; biosensors; blood serum;     Show all 3 Subjects
Abstract:
... Antifouling electrochemical biosensors based on designed all-in-one branched peptides that combine anchoring, doping, antifouling and recognizing functions were constructed to support sensitive and reliable protein quantification in complex serum samples. ...
DOI:
10.1039/d0cc07220f

13. Intracellular mineralization of gold nanoparticles using gold ion-binding peptides with cell-penetrating ability

Author:
Ozaki, Makoto; Yoshida, Shuhei; Tsuruoka, Takaaki; Usui, Kenji
Source:
Chemical communications 2021 v.57 no.6 pp. 725-728
ISSN:
1364-548X
Subject:
peptides,   etc   ; gold; mineralization; nanogold;     Show all 4 Subjects
Abstract:
... We developed a system to directly produce gold nanoparticles in cells by intracellular mineralization in lower concentration than conventional methods using a peptide consisting of a cell-penetrating sequence and a gold ion-binding sequence. Furthermore, we could control the uniquely shaped gold nanostructures that were produced by changing peptide structures. ...
DOI:
10.1039/d0cc06117d

14. Traceless solid-phase synthesis and β-turn propensity of 1,3-thiazole-based peptidomimetics

Author:
Abdildinova, Aizhan; Gong, Young-Dae
Source:
RSC advances 2021 v.11 no.2 pp. 1050-1056
ISSN:
2046-2069
Subject:
peptides,   etc   ; geometry; polystyrenes; sulfur;     Show all 4 Subjects
Abstract:
... The design and solid-phase synthesis of 1,3-thiazole-based peptidomimetic molecules is described. The solid-phase synthesis was based on the utilization of a traceless linker strategy. The synthesis starts from the conversion of chloromethyl polystyrene resin to the resin with a sulfur linker unit. The key intermediate 4-amino-thiazole-5-carboxylic acid resin is prepared in three steps from Merrif ...
DOI:
10.1039/d0ra10127c

15. Expanding the range of sub/supercritical fluid chromatography: Advantageous use of methanesulfonic acid in water-rich modifiers for peptide analysis

Author:
Losacco, Gioacchino Luca; DaSilva, Jimmy Oliviera; Liu, Jinchu; Regalado, Erik L.; Veuthey, Jean-Luc; Guillarme, Davy
Source:
Journal of chromatography 2021 v.1642 pp. 462048
ISSN:
0021-9673
Subject:
cyclic peptides; synthetic peptides,   etc   ; acidity; commercialization; supercritical fluid chromatography;     Show all 5 Subjects
Abstract:
... The aim of this work was to expand the applicability range of UHPSFC to series of synthetic and commercialized peptides. Initially, a screening of different column chemistries available for UHPSFC analysis was performed, in combination with additives of either basic or acidic nature. The combination of an acidic additive (13 mM TFA) with a basic stationary phase (Torus DEA and 2-PIC) was found to ...
DOI:
10.1016/j.chroma.2021.462048

16. Omics-based strategies to discover novel classes of RiPP natural products

Author:
Kloosterman, Alexander M; Medema, Marnix H; van Wezel, Gilles P
Source:
Current opinion in biotechnology 2021 v.69 pp. 60-67
ISSN:
0958-1669
Subject:
peptides,   etc   ; artificial intelligence; biosynthesis; biotechnology;     Show all 4 Subjects
Abstract:
... Ribosomally synthesized and post-translationally modified peptides (RiPPs) form a highly diverse class of natural products, with various biotechnologically and clinically relevant activities. A recent increase in discoveries of novel RiPP classes suggests that currently known RiPPs constitute just the tip of the iceberg. Genome mining has been a driving force behind these discoveries, but remains ...
DOI:
10.1016/j.copbio.2020.12.008

17. Cellular self‐cannibalism helps immune cells fight the flu

Author:
Postoak, Joshua Luke; Yang, Guan; Wu, Lan; Van Kaer, Luc
Source:
TheFEBS journal 2021 v.288 no.10 pp. 3154-3158
ISSN:
1742-464X
Subject:
peptides,   etc   ; Orthomyxoviridae; antigens; autophagy; influenza;     Show all 5 Subjects
Abstract:
... CD4 T cells are critical for generating protective immune responses to infection with influenza virus. Although most CD4 T cells react with peptides from extracellular sources, many react with peptides from viral particles synthesized inside cells; however, the pathways employed for processing the latter antigens remain uncertain. Deng et al. provide evidence for a role of autophagy, a cellular se ...
DOI:
10.1111/febs.15641

18. Peptide Bond Formation of Amino Acids by Transient Masking with Silylating Reagents

Author:
Muramatsu, Wataru; Yamamoto, Hisashi
Source:
Journal of the American Chemical Society 2021 v.143 no.18 pp. 6792-6797
ISSN:
1520-5126
Subject:
peptides,   etc   ; chemoselectivity; imidazole; polymerization; silylation;     Show all 5 Subjects
Abstract:
... A one-pot peptide bond-forming reaction has been developed using unprotected amino acids and peptides. Two different silylating reagents, HSi[OCH(CF₃)₂]₃ and MTBSTFA, are instrumental for the successful implementation of this approach, being used for the activation and transient masking of unprotected amino acids and peptides at C-termini and N-termini, respectively. Furthermore, CsF and imidazole ...
DOI:
10.1021/jacs.1c02600

19. Molecular Oxygen-Mediated Radical Alkylation of C(sp³)–H Bonds with Boronic Acids

Author:
Yang, Le; Qiu, Zhihong; Wu, Jintao; Zhao, Jianyou; Shen, Tong; Huang, Xuan; Liu, Zhong-Quan
Source:
Organic letters 2021 v.23 no.8 pp. 3207-3210
ISSN:
1523-7052
Subject:
peptides,   etc   ; alkylation; boronic acids; oxygen;     Show all 4 Subjects
Abstract:
... A direct and site-specific alkylation of (sp³)C–H bond with aliphatic boronic acid was achieved. By simply heating glycinates and amines together with alkylboronic acids under an oxygen atmosphere, a variety of unnatural α-amino acids and peptides could be obtained in good yields. ...
DOI:
10.1021/acs.orglett.1c00948

20. Epitope-imprinted polymers: applications in protein recognition and separation

Author:
Khumsap, Tabkrich; Corpuz, Angelica; Nguyen, Loc Thai
Source:
RSC advances 2021 v.11 no.19 pp. 11403-11414
ISSN:
2046-2069
Subject:
peptides,   etc   ; epitopes; molecular imprinting; polymerization;     Show all 4 Subjects
Abstract:
... Molecularly imprinted polymers (MIPs) have evolved as promising platforms for specific recognition of proteins. However, molecular imprinting of the whole protein molecule is complicated by its large size, conformational instability, and structural complexity. These inherent limitations can be overcome by using epitope imprinting. Significant breakthroughs in the synthesis and application of epito ...
DOI:
10.1039/d0ra10742e