Synthesis, characterization and systematic comparison of FITC ‐labelled GnRH‐I, ‐II and ‐III analogues on various tumour cells
Targeted tumour therapy is the focus of recent cancer research. Gonadotropin‐releasing hormone (GnRH) analogues are able to deliver anticancer agents selectively into tumour cells, which highly express GnRH receptors. However, the effectiveness of different analogues as targeting moiety in drug delivery systems is rarely compared, and the investigated types of cancer are also limited. Therefore, we prepared selectively labelled, fluorescent derivatives of GnRH‐I, ‐II and ‐III analogues, which were successfully used for drug targeting. In this manuscript, we investigated these analogues' solubility, stability and pa...
Source: Journal of Peptide Science - July 21, 2016 Category: Biochemistry Authors: J ózsef Murányi, Pál Gyulavári, Attila Varga, Györgyi Bökönyi, Henriette Tanai, Tibor Vántus, Domonkos Pap, Krisztina Ludányi, Gábor Mező, György Kéri Tags: Research Article Source Type: research
The impact of β‐azido(or 1‐piperidinyl)methylamino acids in position 2 or 3 on biological activity and conformation of dermorphin analogues
The synthesis of new dermorphin analogues is described. The (R)‐alanine or phenylalanine residues of natural dermorphin were substituted by the corresponding α‐methyl‐β‐azidoalanine or α‐benzyl‐β‐azido(1‐piperidinyl)alanine residues. The potency and selectivity of the new analogues were evaluated by a competitive receptor binding assay in rat brain using [3H]DAMGO (a μ ligand) and [3H]DELT (a δ ligand). The most active analogue in this series, Tyr‐(R)‐Ala‐(R)‐α‐benzyl‐β‐azidoAla‐Gly‐Tyr‐Pro‐Ser‐NH2 and its epimer were analysed by 1H and 13C NMR spectroscopy and restrained mol...
Source: Journal of Peptide Science - July 21, 2016 Category: Biochemistry Authors: Maciej Maciejczyk, Anika Lasota, Oliwia Fr ączak, Piotr Kosson, Aleksandra Misicka, Michał Nowakowski, Andrzej Ejchart, Aleksandra Olma Tags: Research Article Source Type: research
Targeting the SH3 domain of human osteoclast ‐stimulating factor with rationally designed peptoid inhibitors
Human osteoclast‐stimulating factor (hOSF) is an intracellular protein produced by osteoclasts that induces osteoclast formation and bone resorption. The protein contains a modular Src homology 3 (SH3) domain that mediates the intermolecular recognition and interaction of hOSF with its biological partners. Here, we proposed targeting the hOSF SH3 domain to disrupt hOSF–partner interactions for bone disease therapy by using SH3 inhibitors. In the procedure, the primary sequences of three known hOSF‐interacting proteins (c‐Src, SMN and Sam68) were parsed, from which totally 31 octapeptide segments that contain the co...
Source: Journal of Peptide Science - July 21, 2016 Category: Biochemistry Authors: Shijie Han, Qian Liu, Feng Wang, Zenong Yuan Tags: Research Article Source Type: research
Cyclodimerization of immunosuppressive fragment of HLA ‐DR molecule. Design, synthesis and ESI‐MS/MS analysis
The nonapeptide fragment of the HLA‐DR molecule, located in the exposed loop of the alpha‐chain (164–172), having the VPRSGEVYT sequence, suppresses the immune response. Based on the three‐dimensional structure of the HLA‐DR superdimer, we designed a new cyclodimeric analog in which the two parallel peptide chains of VPRSGEVYT sequence are linked through their C‐termini by spacer of (Gly5)2‐Lys‐NH2 and the N‐termini are also linked by poly(ethylene glycol). The (VPRSGEVYTG5)2K‐resin analog was synthesized using solid‐phase peptide synthesis protocols. The cyclization was achieved by cross‐linking th...
Source: Journal of Peptide Science - July 21, 2016 Category: Biochemistry Authors: Monika Biernat, Marzena Cydzik, Piotr Stefanowicz, Alicja Kluczyk, Jolanta Artym, Micha ł Zimecki, Zbigniew Szewczuk Tags: Research Article Source Type: research
Sequences of stilboflavin C: towards the peptaibiome of the filamentous fungus Stilbella (= Trichoderma) flavipes
Filamentous fungi of the genus Stilbella are recognized as an abundant source of naturally occurring α‐aminoisobutyric acid‐containing peptides. The culture broth of Stilbella (Trichoderma) flavipes CBS 146.81 yielded a mixture of peptides named stilboflavins (SF), and these were isolated and separated by preparative TLC into groups named SF‐A, SF‐B, and SF‐C. Although all three of these groups resolved as single spots on thin‐layer chromatograms, HPLC analysis revealed that each of the groups represents very microheterogeneous mixtures of closely related peptides. Here, we report on the sequence analysis of S...
Source: Journal of Peptide Science - July 21, 2016 Category: Biochemistry Authors: Thomas Degenkolb, Lutz G ötze, Hans Döhren, Andreas Vilcinskas, Hans Brückner Tags: Research Article Source Type: research
On the synthesis of cyclodextrin –peptide conjugates by the Huisgen reaction
We present here results of the synthesis of model conjugates formed between CDX and representative peptides by click chemistry. Notably, bis‐conjugation of peptides onto a unique scaffold promotes α‐helix formation. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.
Bis‐coupling of peptide to α‐cyclodextrin by the Huisgen reaction was reported provided long enough linker was used. The resulting conjugates display a propensity to form α‐helix in water. (Source: Journal of Peptide Science)
Source: Journal of Peptide Science - July 21, 2016 Category: Biochemistry Authors: R émy Lartia, Christopher K. Jankowski, Sébastien Arseneau Tags: Rapid Communication Source Type: research
Crystallographic characterization of the α,γ C12 helix in hybrid peptide sequences
The solid‐state conformations of two αγ hybrid peptides Boc‐[Aib‐γ4(R)Ile]4‐OMe 1 and Boc‐[Aib‐γ4(R)Ile]5‐OMe 2 are described. Peptides 1 and 2 adopt C12‐helical conformations in crystals. The structure of octapeptide 1 is stabilized by six intramolecular 4 → 1 hydrogen bonds, forming 12 atom C12 motifs. The structure of peptide 2 reveals the formation of eight successive C12 hydrogen‐bonded turns. Average backbone dihedral angles for αγ C12 helices are peptide 1, Aib; φ (°) = −57.2 ± 0.8, ψ (°) = −44.5 ± 4.7; γ4(R)Ile; φ (°) = −127.3 ± 7.3, θ1 (°) =...
Source: Journal of Peptide Science - July 21, 2016 Category: Biochemistry Authors: Madhusudana M. B. Reddy, Krishnayan Basuroy, Subrayashastry Aravinda, Padmanabhan Balaram Tags: Rapid Communication Source Type: research
Issue Information
(Source: Journal of Peptide Science)
Source: Journal of Peptide Science - July 21, 2016 Category: Biochemistry Tags: Issue Information Source Type: research
Ribosomal binding and antibacterial activity of ethylene glycol ‐bridged apidaecin Api137 and oncocin Onc112 conjugates
In conclusion, Api137/Onc112‐conjugates showed increased antimicrobial activities against P. aeruginosa and PrAMP‐susceptible and ‐resistant E. coli most likely because of improved membrane interactions, whereas the interaction to the 70S ribosome was most likely not improved relying still on the independent apidaecin‐ and oncocin‐type binding modes. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.
Proline‐rich antimicrobial peptides intracellularly inhibit 70S ribosomes utilizing an apidaecin‐ or oncocin‐type binding. Development of a bifunctional inhibitor targeted for bridging ...
Source: Journal of Peptide Science - July 12, 2016 Category: Biochemistry Authors: Tina Goldbach, Daniel Knappe, Christoph Reinsdorf, Thorsten Berg, Ralf Hoffmann Tags: Research Article Source Type: research
Constructing thioether ‐tethered cyclic peptides via on‐resin intra‐molecular thiol–ene reaction
Thiol–ene reactions have been used in a variety of applications that mostly involve an inter‐molecular pathway. Herein, we report a facile method to construct thioether‐tethered cyclic peptides via an intra‐molecular thiol–ene reaction. This reaction is efficient, selective, and has good residue compatibility. Short peptides with thioether tethers were constructed and were used to construct longer cyclic peptides. This synthetic method may be useful for constructing bioactive peptides. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.
Herein, we report a facile method to construct thioet...
Source: Journal of Peptide Science - July 4, 2016 Category: Biochemistry Authors: Bingchuan Zhao, Qingzhou Zhang, Zigang Li Tags: Research Article Source Type: research
Chemically synthesized peptide libraries as a new source of BBB shuttles. Use of mass spectrometry for peptide identification
The blood–brain barrier (BBB) is a biological barrier that protects the brain from neurotoxic agents and regulates the influx and efflux of molecules required for its correct function. This stringent regulation hampers the passage of brain parenchyma‐targeting drugs across the BBB. BBB shuttles have been proposed as a way to overcome this hurdle because these peptides can not only cross the BBB but also carry molecules which would otherwise be unable to cross the barrier unaided. Here we developed a new high‐throughput screening methodology to identify new peptide BBB shuttles in a broadly unexplored chemical space. ...
Source: Journal of Peptide Science - June 30, 2016 Category: Biochemistry Authors: B. Guixer, X. Arroyo, I. Belda, E. Sabid ó, M. Teixidó, E. Giralt Tags: Research Article Source Type: research
Ribosomal binding and antibacterial activity of ethylene glycol‐bridged apidaecin Api137 and oncocin Onc112 conjugates
In conclusion, Api137/Onc112‐conjugates showed increased antimicrobial activities against P. aeruginosa and PrAMP‐susceptible and ‐resistant E. coli most likely because of improved membrane interactions, whereas the interaction to the 70S ribosome was most likely not improved relying still on the independent apidaecin‐ and oncocin‐type binding modes. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.
Proline‐rich antimicrobial peptides intracellularly inhibit 70S ribosomes utilizing an apidaecin‐ or oncocin‐type binding. Development of a bifunctional inhibitor targeted for bridging ...
Source: Journal of Peptide Science - June 30, 2016 Category: Biochemistry Authors: Tina Goldbach, Daniel Knappe, Christoph Reinsdorf, Thorsten Berg, Ralf Hoffmann Tags: Research Article Source Type: research
Constructing thioether‐tethered cyclic peptides via on‐resin intra‐molecular thiol–ene reaction
Thiol–ene reactions have been used in a variety of applications that mostly involve an inter‐molecular pathway. Herein, we report a facile method to construct thioether‐tethered cyclic peptides via an intra‐molecular thiol–ene reaction. This reaction is efficient, selective, and has good residue compatibility. Short peptides with thioether tethers were constructed and were used to construct longer cyclic peptides. This synthetic method may be useful for constructing bioactive peptides. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.
Herein, we report a facile method to construct thioet...
Source: Journal of Peptide Science - June 30, 2016 Category: Biochemistry Authors: Bingchuan Zhao, Qingzhou Zhang, Zigang Li Tags: Research Article Source Type: research
Issue Information
(Source: Journal of Peptide Science)
Source: Journal of Peptide Science - June 29, 2016 Category: Biochemistry Tags: Issue Information Source Type: research
Identification of a female spawn ‐associated Kazal‐type inhibitor from the tropical abalone Haliotis asinina
Abalone (Haliotis) undergoes a period of reproductive maturation, followed by the synchronous release of gametes, called broadcast spawning. Field and laboratory studies have shown that the tropical species Haliotis asinina undergoes a two‐week spawning cycle, thus providing an excellent opportunity to investigate the presence of endogenous spawning‐associated peptides. In female H. asinina, we have isolated a peptide (5145 Da) whose relative abundance in hemolymph increases substantially just prior to spawning and is still detected using reverse‐phase high‐performance liquid chromatography chromatograms up to 1...
Source: Journal of Peptide Science - June 28, 2016 Category: Biochemistry Authors: Tianfang Wang, Parinyaporn Nuurai, Carmel McDougall, Patrick S. York, Utpal Bose, Bernard M. Degnan, Scott F. Cummins Tags: Research Article Source Type: research
