Issue information
(Source: Journal of Peptide Science)
Source: Journal of Peptide Science - August 14, 2017 Category: Biochemistry Tags: Issue Information Source Type: research
Antimicrobial activity of leucine ‐substituted decoralin analogs with lower hemolytic activity
Linear cationic α‐helical antimicrobial peptides are promising chemotherapeutics. Most of them act by different mechanisms, making it difficult to microorganisms acquiring resistance. Decoralin is an example of antimicrobial peptide; it was described by Konno et al. and presented activity against microorganisms, but with pronounced hemolytic activity. We synthesized leucine‐substituted decoralin analogs designed based on important physicochemical properties, which depend on the maintenance of the amphiphilic α‐helical tendency of the native molecule. Peptides were synthesized, purified, and characterized, and the c...
Source: Journal of Peptide Science - August 10, 2017 Category: Biochemistry Authors: Marcelo Der Torossian Torres, Cibele Nicolaski Pedron, Julia Aparecida Lima, Pedro Ismael Silva, Fernanda Dias Silva, Vani Xavier Oliveira Tags: Research Article Source Type: research
Editorial
(Source: Journal of Peptide Science)
Source: Journal of Peptide Science - August 7, 2017 Category: Biochemistry Authors: Luis Moroder, Yoshiaki Kiso, Ulf Diederichsen, Tadashi Teshima Tags: Editorial Source Type: research
Issue information
(Source: Journal of Peptide Science)
Source: Journal of Peptide Science - August 7, 2017 Category: Biochemistry Tags: Issue Information Source Type: research
Dissecting the behaviour of β‐amyloid peptide variants during oligomerization and fibrillation
In this study, the oligomerization and fibrillation abilities of the Aβ variants Aβ1–28, Aβ1–36, Aβ11–42, Aβ17–42, Aβ1–40 and Aβ1–42 were examined by thioflavin T fluorescence, western blotting and transmission electron microscopy. Compared with two C‐terminal‐truncated peptides (i.e. Aβ1–28 and Aβ1–36), Aβ11–42, Aβ17–42 and Aβ1–42 had stronger abilities to form oligomers. This indicated that amino acids 37–42 strengthen the β‐hairpin structure of Aβ. Both Aβ1–42 and Aβ1–40 could form fibres, but Aβ17–42 formed irregular fibres, suggesting that amino acids 1–17 were es...
Source: Journal of Peptide Science - July 1, 2017 Category: Biochemistry Authors: Jing ‐Ming Shi, Lin Zhang, En‐Qi Liu Tags: Research Article Source Type: research
Joseph Rudinger memorial lecture: Unexpected functions of angiotensin converting enzyme, beyond its enzymatic activity
Angiotensin converting enzyme (ACE) is a well‐known enzyme, largely studied for its action on hypertension, as it produces angiotensin II from angiotensin I. This paper describes two original behaviours of ACE. We showed that ACE could hydrolyse gastrin, a neuropeptide from the gastrointestinal tract, releasing the C‐terminal amidated dipeptide H‐Asp‐Phe‐NH2. This dipeptide is believed to be involved in the gastrin‐induced acid secretion in the stomach. This hypothetic mechanism of action of gastrin resulted in a strategy to rationally design gastrin receptor antagonists. Beyond, we showed that the brain renin ...
Source: Journal of Peptide Science - June 19, 2017 Category: Biochemistry Authors: Jean Martinez Tags: Review Source Type: research
Unexpected functions of angiotensin converting enzyme, beyond its enzymatic activity
Angiotensin converting enzyme (ACE) is a well‐known enzyme, largely studied for its action on hypertension, as it produces angiotensin II from angiotensin I. This paper describes two original behaviours of ACE. We showed that ACE could hydrolyse gastrin, a neuropeptide from the gastrointestinal tract, releasing the C‐terminal amidated dipeptide H‐Asp‐Phe‐NH2. This dipeptide is believed to be involved in the gastrin‐induced acid secretion in the stomach. This hypothetic mechanism of action of gastrin resulted in a strategy to rationally design gastrin receptor antagonists. Beyond, we showed that the brain renin ...
Source: Journal of Peptide Science - June 19, 2017 Category: Biochemistry Authors: Jean Martinez Tags: Review Source Type: research
Pyrazole amino acids: hydrogen bonding directed conformations of 3 ‐amino‐1H‐pyrazole‐5‐carboxylic acid residue
A series of model compounds containing 3‐amino‐1H‐pyrazole‐5‐carboxylic acid residue with N‐terminal amide/urethane and C‐terminal amide/hydrazide/ester groups were investigated by using NMR, Fourier transform infrared, and single‐crystal X‐ray diffraction methods, additionally supported by theoretical calculations. The studies demonstrate that the most preferred is the extended conformation with torsion angles ϕ and ψ close to ±180°. The studied 1H‐pyrazole with N‐terminal amide/urethane and C‐terminal amide/hydrazide groups solely adopts this energetically favored conformation confirming rigid...
Source: Journal of Peptide Science - June 13, 2017 Category: Biochemistry Authors: Anna Kusakiewicz ‐Dawid, Monika Porada, Wioletta Ochędzan‐Siodłak, Małgorzata A. Broda, Maciej Bujak, Dawid Siodłak Tags: Research Article Source Type: research
Simple method to assess stability of immobilized peptide ligands against proteases
Although peptides are used as affinity chromatography ligands, they could be digested by proteases. Usually, peptide stability is evaluated in solution, which differs from the resin‐bounded peptide behavior. Furthermore, the study of the degradation products requires purification steps before analysis. Here, we describe an easy method to assess immobilized peptide stability. Sample peptides were synthesized on hydroxymethylbenzamide‐ChemMatrix resin. Peptidyl‐resin beads were then incubated with solutions containing proteases. Peptides were detached from the solid support with ammonia vapor and analyzed by matrix‐a...
Source: Journal of Peptide Science - June 5, 2017 Category: Biochemistry Authors: Silvana L. Giudicessi, Mar ía L. Salum, Soledad L. Saavedra, María C. Martínez‐Ceron, Osvaldo Cascone, Rosa Erra‐Balsells, Silvia A. Camperi Tags: Research Article Source Type: research
IgY ‐binding peptide screened from a random peptide library as a ligand for IgY purification
In this study, we developed a simple IgY purification system using IgY‐specific peptides identified by T7 phage display technology. From disulfide‐constrained random peptide libraries constructed on a T7 phage, we identified three specific binding clones (Y4‐4, Y5‐14, and Y5‐55) through repeated biopanning. The synthetic peptides showed high binding specificity to IgY‐Fc and moderate affinity for IgY‐Fc (Kd: Y4‐4 = 7.3 ± 0.2 μM and Y5‐55 = 4.4 ± 0.1 μM) by surface plasmon resonance analysis. To evaluate the ability to purify IgY, we performed immunoprecipitation and affinity high‐performan...
Source: Journal of Peptide Science - June 1, 2017 Category: Biochemistry Authors: Kamrul Hasan Khan, Arisa Himeno, Shouhei Kosugi, Yosuke Nakashima, Abdur Rafique, Ayana Imamura, Takaaki Hatanaka, Dai ‐Ichiro Kato, Yuji Ito Tags: Research Article Source Type: research
Evaluation of free or anchored antimicrobial peptides as candidates for the prevention of orthopaedic device ‐related infections
The prevention of implant‐associated infection, one the most feared complications in orthopaedic surgery, remains a major clinical challenge and urges development of effective methods to prevent bacterial colonization of implanted devices. Alpha‐helical antimicrobial peptides (AMPs) may be promising candidates in this respect due to their potent and broad‐spectrum antimicrobial activity, their low tendency to elicit resistance and possible retention of efficacy in the immobilized state.
The aim of this study was to evaluate the potential of five different helical AMPs, the cathelicidins BMAP‐27 and BMAP‐28, their...
Source: Journal of Peptide Science - June 1, 2017 Category: Biochemistry Authors: Francesca D'Este, Debora Oro, Gerard Boix ‐Lemonche, Alessandro Tossi, Barbara Skerlavaj Tags: Research Article Source Type: research
Cytotoxic peptides with insulin ‐releasing activities from skin secretions of the Italian stream frog Rana italica (Ranidae)
Peptidomic analysis of norepinephrine‐stimulated skin secretions from Italian stream frog Rana italica led to the purification and characterization of two host‐defense peptides differing by a single amino acid residue belonging to the brevinin‐1 family (brevinin‐1ITa and ‐1ITb), a peptide belonging to the temporin family (temporin‐ITa) and a component identified as prokineticin Bv8. The secretions contained relatively high concentrations of the methionine‐sulphoxide forms of brevinin‐1ITa and ‐1ITb suggesting that these peptides may have a role as antioxidants in the skin of this montane frog. Brevinin‐...
Source: Journal of Peptide Science - June 1, 2017 Category: Biochemistry Authors: J. Michael Conlon, Vishal Musale, Samir Attoub, Maria Luisa Mangoni, J érôme Leprince, Laurent Coquet, Thierry Jouenne, Yasser H. A. Abdel‐Wahab, Peter R. Flatt, Andrea C. Rinaldi Tags: Research Article Source Type: research
Re ‐evaluating the stability of COMU in different solvents
COMU is uronium‐type coupling reagent based on OxymaPure. It showed several advantages over classical benzotriazole‐based coupling reagents such as higher solubility, water‐soluble byproduct, and monitoring the reaction by changing of color. Although COMU is well known to perform excellent in solution, but its hydrolytic stability in DMF limits its use in automatic peptide synthesizer. Herein, we evaluated the hydrolytic stability of COMU in γ‐valerolactone (GVL), acetonitrile (ACN) and N‐formylmorpholine (NFM) and compared its stability against DMF. The stability of COMU after 24 h was found to be 88 and 89% i...
Source: Journal of Peptide Science - June 1, 2017 Category: Biochemistry Authors: Ashish Kumar, Yahya E. Jad, Beatriz G. Torre, Ayman El ‐Faham, Fernando Albericio Tags: Research Article Source Type: research
Cryptophycins: cytotoxic cyclodepsipeptides with potential for tumor targeting
Cryptophycins are a class of 16‐membered highly cytotoxic macrocyclic depsipeptides isolated from cyanobacteria. The biological activity is based on their ability to interact with tubulin. They interfere with microtubule dynamics and prevent microtubules from forming correct mitotic spindles, which causes cell‐cycle arrest and apoptosis. Their strong antiproliferative activities with 100‐fold to 1000‐fold potency compared with those of paclitaxel and vinblastine have been observed. Cryptophycins are highly promising drug candidates, as their biological activity is not negatively affected by P‐glycoprotein, a drug...
Source: Journal of Peptide Science - June 1, 2017 Category: Biochemistry Authors: Christine Weiss, Eduard Figueras, Adina N. Borbely, Norbert Sewald Tags: Special Issue Article Source Type: research
Substitution determination of Fmoc ‐substituted resins at different wavelengths
In solid‐phase peptide synthesis, the nominal batch size is calculated using the starting resin substitution and the mass of the starting resin. The starting resin substitution constitutes the basis for the calculation of a whole set of important process parameters, such as the number of amino acid derivative equivalents. For Fmoc‐substituted resins, substitution determination is often performed by suspending the Fmoc‐protected starting resin in 20% (v/v) piperidine in DMF to generate the dibenzofulvene–piperidine adduct that is quantified by ultraviolet–visible spectroscopy. The spectrometric measurement is perf...
Source: Journal of Peptide Science - June 1, 2017 Category: Biochemistry Authors: Stefan Eissler, Markus Kley, Dirk B ächle, Günther Loidl, Thomas Meier, Daniel Samson Tags: Research Article Source Type: research
