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Iris Lindberg - One of the best experts on this subject based on the ideXlab platform.
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Cationic cell-penetrating peptides are potent furin inhibitors
PLoS ONE, 2015Co-Authors: Bruno Ramos-molina, Donghoon Oh, Adam N. Lick, Naglaa Salem El-sayed, Amir Nasrolahi Shirazi, Keykavous Parang, Rakesh Tiwari, Iris LindbergAbstract:Cationic cell-penetrating peptides have been widely used to enhance the intracellular delivery of various types of cargoes, such as drugs and proteins. These reagents are chemically similar to the multi-basic peptides that are known to be potent proprotein convertase inhibitors. Here, we report that both HIV-1 TAT47-57 peptide and the Chariot reagent are micromolar inhibitors of furin activity in vitro. In agreement, HIV-1 TAT47-57 reduced HT1080 cell migration, thought to be mediated by proprotein convertases, by 25%. In addition, cyclic Polyarginine peptides containing hydrophobic moieties which have been previously used as transfection reagents also exhibited potent furin inhibition in vitro and also inhibited intracellular convertases. Our finding that cationic cell-penetrating peptides exert potent effects on cellular convertase activity should be taken into account when biological effects are assessed.
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Chemical structures of cyclic Polyarginine peptides tested as furin inhibitors.
2015Co-Authors: Bruno Ramos-molina, Adam N. Lick, Naglaa Salem El-sayed, Amir Nasrolahi Shirazi, Keykavous Parang, Rakesh Tiwari, Iris LindbergAbstract:Chemical structures of cyclic Polyarginine peptides tested as furin inhibitors.
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inhibition of furin by Polyarginine containing peptides nanomolar inhibition by nona d arginine
Journal of Biological Chemistry, 2004Co-Authors: Magdalena M Kacprzak, Richard A Houghten, Juan R Peinado, Manuel E Than, Jon R Appel, Stefan Henrich, G M Lipkind, Wolfram Bode, Iris LindbergAbstract:Abstract Polyarginine-containing peptides represent potent inhibitors of furin, a mammalian endoprotease that plays an important role in metabolism, activation of pathogenic toxins, and viral proliferation. The therapeutic use of d-Polyarginines is especially interesting because they are not cleaved by furin and possess inhibitory potency almost equal to l-Polyarginines. In this study we attempted to determine the important elements within Polyarginines that contribute to effective inhibition. Structure-function analyses of Polyarginine peptides showed that inhibition by Polyarginine-containing peptides appeared to depend on the total number of basic charges of the positively charged inhibitors bound to the negatively charged substrate binding pocket; peptide positioning did not appear to be rigorously determined. Screening of l- and d-decapeptide positional scanning combinatorial peptide libraries indicated a preference for basic residues in nearly all positions, similar to previous results with hexapeptide libraries. Length and terminal modification studies showed that the most potent d-Polyarginine tested was nona-d-arginine (D9R) amide with a Ki of 1.3 nm. D9R amide was shown to protect RAW264.7 cells against anthrax toxemia with an IC50 of 3.7 μm. Because of its high stability, specificity, low toxicity, small molecular weight, and extremely low Ki against furin, D9R amide or its derivatives may represent promising compounds for therapeutic use.
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Polyarginines are potent furin inhibitors
Journal of Biological Chemistry, 2000Co-Authors: Angus Cameron, Richard A Houghten, Jon Appel, Iris LindbergAbstract:Abstract The ubiquitous serine endoprotease furin has been implicated in the activation of bacterial toxins and viral glycoproteins as well as in the metastatic progression of certain tumors. Although high molecular mass bioengineered serpin inhibitors have been well characterized, no small nontoxic nanomolar inhibitors have been reported to date. Here we describe the identification of such inhibitors using positional scanning amidated and acetylated syntheticl- and d-hexapeptide combinatorial libraries. The results indicated that l-Arg orl-Lys in all positions generated the most potent inhibitors. However, further investigation revealed that the peptide terminating groups hindered inhibition. Consequently, a series of non-amidated and acetylated Polyarginines was synthesized. The most potent inhibitor identified, nona-l-arginine, had aK i for furin of 40 nm. TheK i values for the related convertases PACE4 and prohormone convertase-1 (PC1) were 110 nm and 2.5 μm, respectively. Although nona-l-arginine was cleaved by furin, the major products after a 6-h incubation at 37 °C were hexa- and hepta-l-arginines, both of which retained the great majority of their potency and specificity against furin. Hexa-d-arginine was as potent and specific a furin inhibitor as hexa-l-arginine (K i values of hexa-d-arginine: 106 nm, 580 nm, and 13.2 μm for furin, PACE4, and PC1, respectively). PC2 was not inhibited by any Polyarginine tested; indeed, PC2 showed an increase in activity of up to 140% of the control in the presence ofl-Polyarginines. Data are also presented that show extended subsite recognition by furin and PC2. Whereas N-terminal acetylation was found to reduce the inhibitory potency of thel-hexapeptide LLRVKR against furin 8-fold, C-terminal amidation reduced the potency <2-fold. Conversely, N-terminal acetylation increased the potency against PC2 nearly 3-fold, whereas C-terminal amidation of the same peptide increased the potency by a factor of 1.6. Our data indicate that non-acetylated, poly-d-arginine-derived molecules may represent excellent lead compounds for the development of therapeutically useful furin inhibitors.
Christopher J Chang - One of the best experts on this subject based on the ideXlab platform.
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bioinspired thiophosphorodichloridate reagents for chemoselective histidine bioconjugation
Journal of the American Chemical Society, 2019Co-Authors: Dan He, Christopher J ChangAbstract:Site-selective bioconjugation to native protein residues is a powerful tool for protein functionalization, with cysteine and lysine side chains being the most common points for attachment owing to their high nucleophilicity. We now report a strategy for histidine modification using thiophosphorodichloridate reagents that mimic post-translational histidine phosphorylation, enabling fast and selective labeling of protein histidines under mild conditions where various payloads can be introduced via copper-assisted alkyne–azide cycloaddition (CuAAC) chemistry. We establish that these reagents are particularly effective at covalent modification of His-tags, which are common motifs to facilitate protein purification, as illustrated by selective attachment of Polyarginine cargoes to enhance the uptake of proteins into living cells. This work provides a starting point for probing and enhancing protein function using histidine-directed chemistry.
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Bioinspired Thiophosphorodichloridate Reagents for Chemoselective Histidine Bioconjugation
2019Co-Authors: Shang Jia, Christopher J ChangAbstract:Site-selective bioconjugation to native protein residues is a powerful tool for protein functionalization, with cysteine and lysine side chains being the most common points for attachment owing to their high nucleophilicity. We now report a strategy for histidine modification using thiophosphorodichloridate reagents that mimic post-translational histidine phosphorylation, enabling fast and selective labeling of protein histidines under mild conditions where various payloads can be introduced via copper-assisted alkyne–azide cycloaddition (CuAAC) chemistry. We establish that these reagents are particularly effective at covalent modification of His-tags, which are common motifs to facilitate protein purification, as illustrated by selective attachment of Polyarginine cargoes to enhance the uptake of proteins into living cells. This work provides a starting point for probing and enhancing protein function using histidine-directed chemistry
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a cell permeable gadolinium contrast agent for magnetic resonance imaging of copper in a menkes disease model
Chemical Science, 2012Co-Authors: Emily L Que, Elizabeth J New, Christopher J ChangAbstract:We present the synthesis and characterization of octaarginine-conjugated Copper-Gad-2 (Arg8CG2), a new copper-responsive magnetic resonance imaging (MRI) contrast agent that combines a Gd3+-DO3A scaffold with a thioether-rich receptor for copper recognition. The inclusion of a Polyarginine appendage leads to a marked increase in cellular uptake compared to previously reported MRI-based copper sensors of the CG family. Arg8CG2 exhibits a 220% increase in relaxivity (r1 = 3.9 to 12.5 mM−1 s−1) upon 1 : 1 binding with Cu+, with a highly selective response to Cu+ over other biologically relevant metal ions. Moreover, Arg8CG2 accumulates in cells at nine-fold greater concentrations than the parent CG2 lacking the Polyarginine functionality and is retained well in the cell after washing. In cellulo relaxivity measurements and T1-weighted phantom images using a Menkes disease model cell line demonstrate the utility of Arg8CG2 to report on biological perturbations of exchangeable copper pools.
Elisabetta Ranucci - One of the best experts on this subject based on the ideXlab platform.
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amphoteric prevailingly cationic l arginine polymers of poly amidoamino acid structure synthesis acid base properties and preliminary cytocompatibility and cell permeating characterizations
Macromolecular Bioscience, 2014Co-Authors: Paolo Ferruti, Nicolo Mauro, L Falciola, V Pifferi, Cristina Bartoli, Matteo Gazzarri, Federica Chiellini, Elisabetta RanucciAbstract:A linear amphoteric poly(amidoamino acid), L-ARGO7, is prepared by Michael-type polyaddition of L-arginine with N,N'-methylenebisacrylamide. Chain-extension of acrylamide end-capped L-ARGO7 oligomers with piperazine leads to high-molecular-weight copolymers in which L-arginine maintains its absolute configuration. Acid/base properties of L-ARGO7 polymers show isolectric points of ≈ 10 and positive net average charges per repeating unit at pH = 7.4 from 0.25 to 0.40. These arginine-rich synthetic polymers possibly share some of the unique biological properties of Polyarginine cell-permeating peptides. In vitro tests with mouse embryo fibroblasts balb/3T3 clone A31 show that L-ARGO7 polymers are endowed with effective cell internalization ability combined with minimal cytotoxicity.
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Amphoteric, Prevailingly Cationic L-Arginine Polymers of Poly(amidoamino acid) Structure: Synthesis, Acid/Base Properties and Preliminary Cytocompatibility and Cell-Permeating Characterizations.
'Wiley', 2014Co-Authors: Paolo Ferruti, Nicolo Mauro, L Falciola, V Pifferi, Cristina Bartoli, Matteo Gazzarri, Federica Chiellini, Elisabetta RanucciAbstract:A linear amphoteric poly(amidoamino acid), L-ARGO7, is prepared by Michael-type polyaddition of L-arginine with N,N0-methylenebisacrylamide. Chain extension of acrylamide end-capped L-ARGO7 oligomers with piperazine leads to high-molecular-weight copolymers in which L-arginine maintains its absolute configuration. Acid/base properties of L-ARGO7 polymers show isolectric points of 10 and positive net average charges per repeating unit at pH\ubc7.4 from 0.25 to 0.40. These arginine-rich synthetic polymers possibly share some of the unique biological properties of Polyarginine cell-permeating peptides. In vitro tests with mouse embryo fibroblasts balb/3T3 clone A31 show that L-ARGO7 polymers are endowed with effective cell internalization ability combined with minimal cytotoxicity
Amir Nasrolahi Shirazi - One of the best experts on this subject based on the ideXlab platform.
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Enhanced cellular uptake of short Polyarginine peptides through fatty acylation and cyclization
2016Co-Authors: Amir Nasrolahi Shirazi, Kevin Northup, Brian Sullivan, Rakesh Kumar Tiwari, Marco BisoffiAbstract:ABSTRACT: Many of the reported arginine-rich cell-penetrating peptides (CPPs) for the enhanced delivery of drugs are linear peptides composed of more than seven arginine residues to retain the cell penetration properties. Herein, we synthesized a class of nine Polyarginine peptides containing 5 and 6 arginines, namely, R5 and R6. We further explored the effect of acylation with long chain fatty acids (i.e., octanoic acid, dodecanoic acid, and hexadecanoic acid) and cyclization on the cell penetrating properties of the peptides. The fluorescence-labeled acylated cyclic peptide dodecanoyl-[R5] and linear peptide dodecanoyl-(R5) showed approximately 13.7- and 10.2-fold higher cellular uptake than that of control 5,6-carboxyfluorescein, respectively. The mechanism of the peptide internalization into cells was found to be energy-dependent endocytosis. Dodecanoyl-[R5] and dodecanoyl-[R6] enhanced the intracellular uptake of a fluorescence-labeled cell-impermeable negatively charged phosphopeptide (F′-GpYEEI) in human ovarian cancer cells (SK-OV-3) by 3.4-fold and 5.5-fold, respectively, as shown by flow cytometry. The cellular uptake of F′-GpYEEI in the presence of hexadecanoyl-[R5] was 9.3- and 6.0-fold higher than that in the presence o
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RESEARCH ARTICLE Cationic Cell-Penetrating Peptides Are Potent Furin Inhibitors
2016Co-Authors: Bruno Ramos-molina, Adam N. Lick, Amir Nasrolahi ShiraziAbstract:Cationic cell-penetrating peptides have been widely used to enhance the intracellular deliv-ery of various types of cargoes, such as drugs and proteins. These reagents are chemically similar to the multi-basic peptides that are known to be potent proprotein convertase inhibi-tors. Here, we report that both HIV-1 TAT47-57 peptide and the Chariot reagent are micromo-lar inhibitors of furin activity in vitro. In agreement, HIV-1 TAT47-57 reduced HT1080 cell migration, thought to be mediated by proprotein convertases, by 25%. In addition, cyclic Polyarginine peptides containing hydrophobic moieties which have been previously used as transfection reagents also exhibited potent furin inhibition in vitro and also inhibited intracel-lular convertases. Our finding that cationic cell-penetrating peptides exert potent effects on cellular convertase activity should be taken into account when biological effects are assessed
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Cationic cell-penetrating peptides are potent furin inhibitors
PLoS ONE, 2015Co-Authors: Bruno Ramos-molina, Donghoon Oh, Adam N. Lick, Naglaa Salem El-sayed, Amir Nasrolahi Shirazi, Keykavous Parang, Rakesh Tiwari, Iris LindbergAbstract:Cationic cell-penetrating peptides have been widely used to enhance the intracellular delivery of various types of cargoes, such as drugs and proteins. These reagents are chemically similar to the multi-basic peptides that are known to be potent proprotein convertase inhibitors. Here, we report that both HIV-1 TAT47-57 peptide and the Chariot reagent are micromolar inhibitors of furin activity in vitro. In agreement, HIV-1 TAT47-57 reduced HT1080 cell migration, thought to be mediated by proprotein convertases, by 25%. In addition, cyclic Polyarginine peptides containing hydrophobic moieties which have been previously used as transfection reagents also exhibited potent furin inhibition in vitro and also inhibited intracellular convertases. Our finding that cationic cell-penetrating peptides exert potent effects on cellular convertase activity should be taken into account when biological effects are assessed.
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Chemical structures of cyclic Polyarginine peptides tested as furin inhibitors.
2015Co-Authors: Bruno Ramos-molina, Adam N. Lick, Naglaa Salem El-sayed, Amir Nasrolahi Shirazi, Keykavous Parang, Rakesh Tiwari, Iris LindbergAbstract:Chemical structures of cyclic Polyarginine peptides tested as furin inhibitors.
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Enhanced Cellular Uptake of Short Polyarginine Peptides through Fatty Acylation and Cyclization
2015Co-Authors: Amir Nasrolahi Shirazi, Kevin Northup, Brian Sullivan, Rakesh Kumar Tiwari, Marco Bisoffi, Keykavous ParangAbstract:Many of the reported arginine-rich cell-penetrating peptides (CPPs) for the enhanced delivery of drugs are linear peptides composed of more than seven arginine residues to retain the cell penetration properties. Herein, we synthesized a class of nine Polyarginine peptides containing 5 and 6 arginines, namely, R5 and R6. We further explored the effect of acylation with long chain fatty acids (i.e., octanoic acid, dodecanoic acid, and hexadecanoic acid) and cyclization on the cell penetrating properties of the peptides. The fluorescence-labeled acylated cyclic peptide dodecanoyl-[R5] and linear peptide dodecanoyl-(R5) showed approximately 13.7- and 10.2-fold higher cellular uptake than that of control 5,6-carboxyfluorescein, respectively. The mechanism of the peptide internalization into cells was found to be energy-dependent endocytosis. Dodecanoyl-[R5] and dodecanoyl-[R6] enhanced the intracellular uptake of a fluorescence-labeled cell-impermeable negatively charged phosphopeptide (F′-GpYEEI) in human ovarian cancer cells (SK-OV-3) by 3.4-fold and 5.5-fold, respectively, as shown by flow cytometry. The cellular uptake of F′-GpYEEI in the presence of hexadecanoyl-[R5] was 9.3- and 6.0-fold higher than that in the presence of octanoyl-[R5] and dodecanoyl-[R5], respectively. Dodecanoyl-[R5] enhanced the cellular uptake of the phosphopeptide by 1.4–2.5-fold higher than the corresponding linear peptide dodecanoyl-(R5) and those of representative CPPs, such as hepta-arginine (CR7) and TAT peptide. These results showed that a combination of acylation by long chain fatty acids and cyclization on short arginine-containing peptides can improve their cell-penetrating property, possibly through efficient interaction of rigid positively charged R and hydrophobic dodecanoyl moiety with the corresponding residues in the cell membrane phospholipids
Bruno Ramos-molina - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Cationic Cell-Penetrating Peptides Are Potent Furin Inhibitors
2016Co-Authors: Bruno Ramos-molina, Adam N. Lick, Amir Nasrolahi ShiraziAbstract:Cationic cell-penetrating peptides have been widely used to enhance the intracellular deliv-ery of various types of cargoes, such as drugs and proteins. These reagents are chemically similar to the multi-basic peptides that are known to be potent proprotein convertase inhibi-tors. Here, we report that both HIV-1 TAT47-57 peptide and the Chariot reagent are micromo-lar inhibitors of furin activity in vitro. In agreement, HIV-1 TAT47-57 reduced HT1080 cell migration, thought to be mediated by proprotein convertases, by 25%. In addition, cyclic Polyarginine peptides containing hydrophobic moieties which have been previously used as transfection reagents also exhibited potent furin inhibition in vitro and also inhibited intracel-lular convertases. Our finding that cationic cell-penetrating peptides exert potent effects on cellular convertase activity should be taken into account when biological effects are assessed
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Cationic cell-penetrating peptides are potent furin inhibitors
PLoS ONE, 2015Co-Authors: Bruno Ramos-molina, Donghoon Oh, Adam N. Lick, Naglaa Salem El-sayed, Amir Nasrolahi Shirazi, Keykavous Parang, Rakesh Tiwari, Iris LindbergAbstract:Cationic cell-penetrating peptides have been widely used to enhance the intracellular delivery of various types of cargoes, such as drugs and proteins. These reagents are chemically similar to the multi-basic peptides that are known to be potent proprotein convertase inhibitors. Here, we report that both HIV-1 TAT47-57 peptide and the Chariot reagent are micromolar inhibitors of furin activity in vitro. In agreement, HIV-1 TAT47-57 reduced HT1080 cell migration, thought to be mediated by proprotein convertases, by 25%. In addition, cyclic Polyarginine peptides containing hydrophobic moieties which have been previously used as transfection reagents also exhibited potent furin inhibition in vitro and also inhibited intracellular convertases. Our finding that cationic cell-penetrating peptides exert potent effects on cellular convertase activity should be taken into account when biological effects are assessed.
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Chemical structures of cyclic Polyarginine peptides tested as furin inhibitors.
2015Co-Authors: Bruno Ramos-molina, Adam N. Lick, Naglaa Salem El-sayed, Amir Nasrolahi Shirazi, Keykavous Parang, Rakesh Tiwari, Iris LindbergAbstract:Chemical structures of cyclic Polyarginine peptides tested as furin inhibitors.