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1.

001-es BibID:BIBFORM113131
035-os BibID:(cikkazonosító)121 (scopus)85160315499 (wos)000994418900002
Első szerző:Ashwood, Lauren M.
Cím:Genomic, functional and structural analyses elucidate evolutionary innovation within the sea anemone 8 toxin family / Ashwood Lauren M., Elnahriry Khaled A., Stewart Zachary K., Shafee Thomas, Naseem Muhammad Umair, Szanto Tibor G., van der Burg Chloé A., Smith Hayden L., Surm Joachim M., Undheim Eivind A. B., Madio Bruno, Hamilton Brett R., Guo Shaodong, Wai Dorothy C. C., Coyne Victoria L., Phillips Matthew J., Dudley Kevin J., Hurwood David A., Panyi Gyorgy, King Glenn F., Pavasovic Ana, Norton Raymond S., Prentis Peter J.
Dátum:2023
ISSN:1741-7007
Megjegyzések:Background The ShK toxin from Stichodactyla helianthus has established the therapeutic potential of sea anemone venom peptides, but many lineage-specific toxin families in Actiniarians remain uncharacterised. One such peptide family, sea anemone 8 (SA8), is present in all five sea anemone superfamilies. We explored the genomic arrangement and evolution of the SA8 gene family in Actinia tenebrosa and Telmatactis stephensoni, characterised the expression patterns of SA8 sequences, and examined the structure and function of SA8 from the venom of T. stephensoni. Results We identified ten SA8-family genes in two clusters and six SA8-family genes in five clusters for T. stephen- soni and A. tenebrosa, respectively. Nine SA8 T. stephensoni genes were found in a single cluster, and an SA8 peptide encoded by an inverted SA8 gene from this cluster was recruited to venom. We show that SA8 genes in both spe- cies are expressed in a tissue-specific manner and the inverted SA8 gene has a unique tissue distribution. While the functional activity of the SA8 putative toxin encoded by the inverted gene was inconclusive, its tissue localisation is similar to toxins used for predator deterrence. We demonstrate that, although mature SA8 putative toxins have similar cysteine spacing to ShK, SA8 peptides are distinct from ShK peptides based on structure and disulfide connectivity. Conclusions Our results provide the first demonstration that SA8 is a unique gene family in Actiniarians, evolving through a variety of structural changes including tandem and proximal gene duplication and an inversion event that together allowed SA8 to be recruited into the venom of T. stephensoni.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:BMC Biology. - 21 : 1 (2023), p. 1-25. -
További szerzők:Elnahriry, Khaled A. Stewart, Zachary K. Shafee, Thomas Naseem, Muhammad Umair (1993-) (biofizikus, molekuláris biológus) Szántó Gábor Tibor (1980-) (vegyész) van der Burg, Chloé A. Smith, Hayden L. Surm, Joachim M. Undheim, Eivind A. B. Madio, Bruno Hamilton, Brett R. Guo, Shaodong Wai, Dorothy C. C. Coyne, Victoria L. Phillips, Matthew J. Dudley, Kevin J. Hurwood, David A. Panyi György (1966-) (biofizikus) King, Glenn F. Pavasovic, Ana Norton, Raymond S. Prentis, Peter
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2.

001-es BibID:BIBFORM052924
Első szerző:Bartók Ádám (biotechnológus)
Cím:Margatoxin is a non-selective inhibitor of human Kv1.3 K+ channels / Adam Bartok, Agnes Toth, Sandor Somodi, Tibor G. Szanto, Peter Hajdu, Gyorgy Panyi, Zoltan Varga
Dátum:2014
ISSN:0041-0101
Megjegyzések:Margatoxin (MgTx), an alpha-KTx scorpion toxin, is considered a selective inhibitor of the Kv1.3 K+ channel. This peptide is widely used in ion channel research; however, a comprehensive study of its selectivity with electrophysiological methods has not been published yet. The lack of selectivity might lead to undesired side effects upon therapeutic application or may lead to incorrect conclusion regarding the role of a particular ion channel in a physiological or pathophysiological response either in vitro or in vivo. Using the patch-clamp technique we characterized the selectivity profile of MgTx using L929 cells expressing mKv1.1 channels, human peripheral lymphocytes expressing Kv1.3 channels and transiently transfected tsA201 cells expressing hKv1.1, hKv1.2, hKv1.3, hKv1.4-IR, hKv1.5, hKv1.6, hKv1.7, rKv2.1, Shaker-IR, hERG, hKCa1.1, hKCa3.1 and hNav1.5 channels. MgTx is indeed a high affinity inhibitor of Kv1.3 (Kd = 11.7 pM) but is not selective, it inhibits the Kv1.2 channel with similar affinity (Kd = 6.4 pM) and Kv1.1 in the nanomolar range (Kd = 4.2 nM). Based on our comprehensive data MgTX has to be considered a non-selective Kv1.3 inhibitor, and thus, experiments aiming at elucidating the significance of Kv1.3 in in vitro or in vivo physiological responses have to be carefully evaluated.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
ion channel
potassium channel
scorpion toxin
margatoxin
Megjelenés:Toxicon. - 87 (2014), p. 6-16. -
További szerzők:Tóth Ágnes (1983-) (biofizikus) Somodi Sándor (1977-) (belgyógyász) Szántó Gábor Tibor (1980-) (vegyész) Hajdu Péter (1975-) (biofizikus) Panyi György (1966-) (biofizikus) Varga Zoltán (1969-) (biofizikus, szakfordító)
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3.

001-es BibID:BIBFORM095264
035-os BibID:(scopus)85107216771 (wos)000655485500001
Első szerző:Bene Zsolt (orvos)
Cím:Enhanced Expression of Human Epididymis Protein 4 (HE4) Reflecting Pro-Inflammatory Status Is Regulated by CFTR in Cystic Fibrosis Bronchial Epithelial Cells / Zsolt Bene, Zsolt Fejes, Tibor Gabor Szanto, Ferenc Fenyvesi, Judit Váradi, Luka A. Clarke, Gyorgy Panyi, Milan Macek Jr., Margarida D. Amaral, István Balogh, Béla Nagy Jr.
Dátum:2021
ISSN:1663-9812
Tárgyszavak:Orvostudományok Klinikai orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Frontiers in Pharmacology. - 12 (2021), p. 1-16. -
További szerzők:Fejes Zsolt (1988-) (molekuláris biológus) Szántó Gábor Tibor (1980-) (vegyész) Fenyvesi Ferenc (1977-) (gyógyszerész, gyógyszertechnológus) Váradi Judit (1973-) (gyógyszerész, gyógyszertechnológus) Clarke, Luka A. Panyi György (1966-) (biofizikus) Macek Jr., Milan Amaral, Margarida D. Balogh István (1972-) (molekuláris biológus, genetikus) Nagy Béla Jr. (1980-) (labordiagnosztikai szakorvos)
Pályázati támogatás:OTKA FK 135327
OTKA
GINOP-2.3.2-15-2016-00043
GINOP
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Intézményi repozitóriumban (DEA) tárolt változat
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4.

001-es BibID:BIBFORM102212
035-os BibID:(cikkazonosító)115023 (WoS)000793623600002 (Scopus)85127510848
Első szerző:Csóti Ágota (biológus)
Cím:sVmKTx, a transcriptome analysis-based synthetic peptide analogue of Vm24, inhibits Kv1.3 channels of human T cells with improved selectivity / Csoti Agota, del Carmen Nájera Meza Rosby, Bogár Ferenc, Tajti Gabor, Szanto Tibor G., Varga Zoltan, Gurrola Georgina B., Tóth Gábor K., Possani Lourival D., Panyi Gyorgy
Dátum:2022
ISSN:0006-2952
Megjegyzések:Kv1.3 K+ channels play a central role in the regulation of T cell activation and Ca2+ signaling under physiological and pathophysiological conditions. Peptide toxins targeting Kv1.3 have a significant therapeutic potential in the treatment of autoimmune diseases; thus, the discovery of new toxins is highly motivated. Based on the transcriptome analysis of the venom gland of V. mexicanus smithi a novel synthetic peptide, sVmKTx was generated, containing 36 amino acid residues. sVmKTx shows high sequence similarity to Vm24, a previously characterized peptide from the same species, but contains a Glu at position 32 as opposed to Lys32 in Vm24. Vm24 inhibits Kv1.3 with high affinity (Kd = 2.9 pM). However, it has limited selectivity (~1,500-fold) for Kv1.3 over hKv1.2, hKCa3.1, and mKv1.1. sVmKTx displays reduced Kv1.3 affinity (Kd = 770 pM) but increased selectivity for Kv1.3 over hKv1.2 (~9,000-fold) as compared to Vm24, other channels tested in the panel (hKCa3.1, hKv1.1, hKv1.4, hKv1.5, rKv2.1, hKv11.1, hKCa1.1, hNav1.5) were practically insensitive to the toxin at 2.5 ?M. Molecular dynamics simulations showed that introduction of a Glu instead of Lys at position 32 led to a decreased structural fluctuation of the N-terminal segment of sVmKTx, which may explain its increased selectivity for Kv1.3. sVmKTx at 100 nM concentration decreased the expression level of the Ca2+ -dependent T cell activation marker, CD40 ligand. The high affinity block of Kv1.3 and increased selectivity over the natural peptide makes sVmKTx a potential candidate for Kv1.3 blockade-mediated treatment of autoimmune diseases.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Kv1.3
Toxin-channel interaction
T-cell activation
Patch-clamp
Ion channel selectivity
Scorpion toxin
Megjelenés:Biochemical Pharmacology. - 199 (2022), p. 1-14. -
További szerzők:del Carmen Nájera Meza, Rosby Bogár Ferenc Tajti Gábor (1988-) (gyógyszerész, biofizikus, sejtbiológus) Szántó Gábor Tibor (1980-) (vegyész) Varga Zoltán (1969-) (biofizikus, szakfordító) Gurrola-Briones, Georgina Tóth Gábor K. Possani, Lourival Domingos Panyi György (1966-) (biofizikus)
Pályázati támogatás:143071
OTKA
K119417
OTKA
K132906
OTKA
EFOP-3.6.2-16-2017-00006
EFOP
GINOP-2.3.2-15-2016-00044
GINOP
PRONACE303045 from National Conseil of Science and Technology of Mexico
Egyéb
Ministry of Human Capacities, Hungary grant, TKP-2020
Egyéb
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Intézményi repozitóriumban (DEA) tárolt változat
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5.

001-es BibID:BIBFORM114859
035-os BibID:(cikkazonosító)140952 (scopus)85170288156
Első szerző:Elnahriry, Khaled A.
Cím:Structural and functional characterisation of Tst2, a novel TRPV1 inhibitory peptide from the Australian sea anemone Telmatactis stephensoni / Elnahriry Khaled A., Wai Dorothy C. C., Ashwood Lauren M., Naseem Muhammad Umair, Szanto Tibor G., Guo Shaodong, Panyi Gyorgy, Prentis Peter J., Norton Raymond S.
Dátum:2024
ISSN:1570-9639
Megjegyzések:Sea anemone venoms are complex mixtures of biologically active compounds, including disulfide-rich peptides, some of which have found applications as research tools, and others as therapeutic leads. Our recent transcriptomic and proteomic studies of the Australian sea anemone Telmatactis stephensoni identified a transcript for a peptide designated Tst2. Tst2 is a 38-residue peptide showing sequence similarity to peptide toxins known to interact with a range of ion channels (NaV, TRPV1, KV and CaV). Recombinant Tst2 (rTst2, which contains an additional Gly at the N-terminus) was produced by periplasmic expression in Escherichia coli, enabling the production of both unlabelled and uniformly 13C,15N?labelled peptide for functional assays and structural studies. The LC-MS profile of the recombinant Tst2 showed a pure peak with molecular mass 6 Da less than that of the reduced form of the peptide, indicating the successful formation of three disulfide bonds from its six cysteine residues. The solution structure of rTst2 was determined using multidimensional NMR spectroscopy and revealed that rTst2 adopts an inhibitor cystine knot (ICK) structure. rTst2 was screened using various functional assays, including patch?clamp electrophysiological and cytotoxicity assays. rTst2 was inactive against voltagegated sodium channels (NaV) and the human voltage-gated proton (hHv1) channel. rTst2 also did not possess cytotoxic activity when assessed against Drosophila melanogaster flies. However, the recombinant peptide at 100 nM showed >50% inhibition of the transient receptor potential subfamily V member 1 (TRPV1) and slight (~10%) inhibition of transient receptor potential subfamily A member 1 (TRPA1). Tst2 is thus a novel ICK inhibitor of the TRPV1 channel.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Sea anemone
Disulfide-rich peptides
Recombinant expression
NMR spectroscopy
ICK scaffold
TRPV1 channel
Megjelenés:Biochimica et Biophysica Acta (BBA). Proteins and Proteomics. - 1872 : 1 (2024), p. 1-13. -
További szerzők:Wai, Dorothy C. C. Ashwood, Lauren M. Naseem, Muhammad Umair (1993-) (biofizikus, molekuláris biológus) Szántó Gábor Tibor (1980-) (vegyész) Guo, Shaodong Panyi György (1966-) (biofizikus) Prentis, Peter Norton, Raymond S.
Pályázati támogatás:K143071
OTKA
Stipendium Hungaricum Scholarship from the Tempus Public Foundation
Egyéb
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Intézményi repozitóriumban (DEA) tárolt változat
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6.

001-es BibID:BIBFORM066284
035-os BibID:(Cikkazonosító)31131 (WOS)000381028800001 (Scopus)84981237531
Első szerző:Fineberg, Jeffrey D.
Cím:Closed-state inactivation involving an internal gate in Kv4.1 channels modulates pore blockade by intracellular quaternary ammonium ions / Jeffrey D. Fineberg, Tibor G. Szanto, Gyorgy Panyi, Manuel Covarrubias
Dátum:2016
ISSN:2045-2322
Megjegyzések:Voltage-gated K+ (Kv) channel activation depends on interactions between voltage sensors and an intracellular activation gate that controls access to a central pore cavity. Here, we hypothesize that this gate is additionally responsible for closed-state inactivation (CSI) in Kv4.x channels. These Kv channels undergo CSI by a mechanism that is still poorly understood. To test the hypothesis, we deduced the state of the Kv4.1 channel intracellular gate by exploiting the trap-door paradigm of pore blockade by internally applied quaternary ammonium (QA) ions exhibiting slow blocking kinetics and high-affinity for a blocking site. We found that inactivation gating seemingly traps benzyl-tributylammonium (bTBuA) when it enters the central pore cavity in the open state. However, bTBuA fails to block inactivated Kv4.1 channels, suggesting gated access involving an internal gate. In contrast, bTBuA blockade of a Shaker Kv channel that undergoes open-state P/C-type inactivation exhibits fast onset and recovery inconsistent with bTBuA trapping. Furthermore, the inactivated Shaker Kv channel is readily blocked by bTBuA. We conclude that Kv4.1 closed-state inactivation modulates pore blockade by QA ions in a manner that depends on the state of the internal activation gate.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Scientific Reports. - 6 (2016), p. 31131-. -
További szerzők:Szántó Gábor Tibor (1980-) (vegyész) Panyi György (1966-) (biofizikus) Covarrubias, Manuel
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Intézményi repozitóriumban (DEA) tárolt változat
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7.

001-es BibID:BIBFORM083629
035-os BibID:(WoS)000518872600011 (Scopus)85078049471 (PMID)31870846
Első szerző:Jin, Jiayi
Cím:Weaponisation 'on the fly' : convergent recruitment of knottin and defensin peptide scaffolds into the venom of predatory assassin flies / Jiayi Jin, Akello J. Agwa, G. Tibor Szanto, Agota Csóti, Gyorgy Panyi, Christina I. Schroeder, Andrew A. Walker, Glenn F. King
Dátum:2020
ISSN:0965-1748
Megjegyzések:Many arthropod venom peptides have potential as bioinsecticides, drug leads, and pharmacological tools due to their specific neuromodulatory functions. Assassin flies (Asilidae) are a family of predaceous dipterans that produce a unique and complex peptide-rich venom for killing insect prey and deterring predators. However, very little is known about the structure and function of their venom peptides. We therefore used an E. coli periplasmic expression system to express four disulfide-rich peptides that we previously reported to exist in venom of the giant assassin fly Dolopus genitalis. After purification, each recombinant peptide eluted from a C18 column at a position closely matching its natural counterpart, strongly suggesting adoption of the native tertiary fold. Injection of purified recombinant peptides into blowflies (Lucilia cuprina) and crickets (Acheta domestica) revealed that two of the four recombinant peptides, named rDg3b and rDg12, inhibited escape behaviour in a manner that was rapid in onset (<1 min) and reversible. Homonuclear NMR solution structures revealed that rDg3b and rDg12 adopt cystine-stabilised α/ß defensin and inhibitor cystine knot folds, respectively. Although the closest known homologues of rDg3b at the level of primary structure are dipteran antimicrobial peptides such as sapecin and lucifensin, a DALI search showed that the tertiary structure of rDg3b most closely resembles the KV11.1-specific α-potassium channel toxin CnErg1 from venom of the scorpion Centruroides noxius. This is mainly due to the deletion of a large, unstructured loop between the first and second cysteine residues present in Dg3b homologues from non-asiloid, but not existing in asiloid, species. Patch-clamp electrophysiology experiments revealed that rDg3b shifts the voltage-dependence of KV11.1 channel activation to more depolarised potentials, but has no effect on KV1.3, KV2.1, KV10.1, KCa1.1, or the Drosophila Shaker channel. Although rDg12 shares the inhibitor cystine knot structure of many gating modifier toxins, rDg12 did not affect any of these KV channel subtypes. Our results demonstrate that multiple disulfide-rich peptide scaffolds have been convergently recruited into asilid and other animal venoms, and they provide insight into the molecular evolution accompanying their weaponisation.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Diptera
Dolopus genitalis
Ion channel
K(V)11.1 (hERG)
Toxin
Megjelenés:Insect Biochemistry and Molecular Biology. - 118 (2020), p. 1-12. -
További szerzők:Agwa, Akello J. Szántó Gábor Tibor (1980-) (vegyész) Csóti Ágota (1989-) (biológus) Panyi György (1966-) (biofizikus) Schroeder, Christina I. Walker, Andrew A. King, Glenn F.
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Intézményi repozitóriumban (DEA) tárolt változat
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8.

001-es BibID:BIBFORM080665
035-os BibID:(WoS)000485145400079 (Scopus)85072013629
Első szerző:Karbat, Izhar
Cím:Pore-modulating toxins exploit inherent slow inactivation to block K+ channels / Izhar Karbat, Hagit Altman-Gueta, Shachar Fine, Tibor Szanto, Shelly Hamer-Rogotner, Orly Dym, Felix Frolow, Dalia Gordon, Gyorgy Panyi, Michael Gurevitz, Eitan Reuveny
Dátum:2019
ISSN:0027-8424 1091-6490
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Proceedings of The National Academy of Sciences of The United States of America. - 116 : 37 (2019), p. 18700-18709. -
További szerzők:Altman-Gueta, Hagit Fine, Shachar Szántó Gábor Tibor (1980-) (vegyész) Hamer-Rogotner, Shelly Dym, Orly Frolow, Felix Gordon, Dalia Panyi György (1966-) (biofizikus) Gurevitz, Michael Reuveny, Eitan
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Intézményi repozitóriumban (DEA) tárolt változat
Borító:

9.

001-es BibID:BIBFORM079020
035-os BibID:(absztrakt azonosító)1849-Plat (WoS)000430450000363
Első szerző:Karbat, Izhar
Cím:An Allosteric Action Mechanism of a K+ Pore Blocker Revealed at the Atomic Level / Izhar Karbat, Hagit Altman-Gueta, G. Tibor Szántó, Shelly Hamer-Rogotner, Orly Dym, Felix Frolow, Dalia Gordon, Gyorgy Panyi, Michael Gurevitz, Eitan Reuveny
Dátum:2018
ISSN:0006-3495
Megjegyzések:Voltage gated ion channels gate in response to changes in the electrical membrane potential by the coupling of a voltage sensing module with an ion-selective pore. Toxins that target these channels are traditionally classified as either pore-blockers or gating-modifiers, the former bind and physically occlude the channel pore, while the later bind the voltage sensing module and restrict its movement in response to alterations in the membrane potential. Here we present Cs1, a kunitz-fold cone-snail toxin that blocks the Drosophila Shaker isoform with high affinity and seem to defy the traditional classification. We first obtained high resolution crystal structures of Cs1 and several of its mutants. Then, using site directed mutagenesis followed by double-mutant cycle analysis we identified key residue pairs in contact at the toxin-channel interface, which was clearly confined to the channel pore-module. Unconstrained rigid docking followed by a whole-atom molecular dynamics simulations yielded a model that was consistent with the experimental results, in which the toxin was bound off the pore axis and allowed the access of water molecules to the pore. Electrophysiological assays established that Cs1 does not dissociate from its binding site upon depolarization, and that its affinity for the channel is independent of the external K+ concentration, further setting it apart from the classical pore-blockers. Analysis of our MD simulations suggest that Cs1 blocks ion conductance using a novel allosteric mechanism that directly involves structural water molecules buried behind the selectivity filter of the channel.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idézhető absztrakt
folyóiratcikk
Megjelenés:Biophysical Journal. - 114 : 3 (2018), p. 375a. -
További szerzők:Altman-Gueta, Hagit Szántó Gábor Tibor (1980-) (vegyész) Hamer-Rogotner, Shelly Dym, Orly Frolow, Felix Gordon, Dalia Panyi György (1966-) (biofizikus) Gurevitz, Michael Reuveny, Eitan
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Intézményi repozitóriumban (DEA) tárolt változat
Borító:

10.

001-es BibID:BIBFORM103992
035-os BibID:(cikkazonosító)10533 (scopus)85138397388 (wos)000857594300001
Első szerző:Mészáros Beáta (molekuláris biológus, mikrobiológus)
Cím:The hEag1 K+ Channel Inhibitor Astemizole Stimulates Ca2+ Deposition in SaOS-2 and MG-63 Osteosarcoma Cultures / Mészáros Beáta, Csoti Agota, Szanto Tibor G., Telek Andrea, Kovács Katalin, Toth Agnes, Volkó Julianna, Panyi Gyorgy
Dátum:2022
ISSN:1422-0067
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:International Journal Of Molecular Sciences. - 23 : 18 (2022), p. 1-19. -
További szerzők:Csóti Ágota (1989-) (biológus) Szántó Gábor Tibor (1980-) (vegyész) Telek Andrea (1977-) (élettanász) Kovács Katalin (1978-) (biokémikus) Tóth Ágnes (1983-) (biofizikus) Volkó Julianna (1983-) (biotechnológus) Panyi György (1966-) (biofizikus)
Pályázati támogatás:EFOP- 3.6.2- 16-2017-00006
EFOP
GINOP-2.3.2-15-2016-00044
GINOP
K143071
OTKA
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Intézményi repozitóriumban (DEA) tárolt változat
Borító:

11.

001-es BibID:BIBFORM103838
035-os BibID:(scopus)85132050297 (cikkazonosító)e202213146
Első szerző:Naseem, Muhammad Umair (biofizikus, molekuláris biológus)
Cím:Cm28, a scorpion toxin having a unique primary structure, inhibits KV1.2 and KV1.3 with high affinity / Naseem Muhammad Umair, Carcamo-Noriega Edson, Beltrán-Vidal José, Borrego Jesus, Szanto Tibor G., Zamudio Fernando Z., Delgado-Prudencio Gustavo, Possani Lourival D., Panyi Gyorgy
Dátum:2022
ISSN:0022-1295 1540-7748
Megjegyzések:The Cm28 in the venom of Centruroides margaritatus is a short peptide consisting of 27 amino acid residues with a mol wt of 2,820 D. Cm28 has <40% similarity with other known ?-KTx from scorpions and lacks the typical functional dyad (lysine?tyrosine) required to block KV channels. However, its unique sequence contains the three disulfide-bond traits of the ?-KTx scorpion toxin family. We propose that Cm28 is the first example of a new subfamily of ?-KTxs, registered with the systematic number ?-KTx32.1. Cm28 inhibited voltage-gated K+ channels KV1.2 and KV1.3 with Kd values of 0.96 and 1.3 nM, respectively. There was no significant shift in the conductance?voltage (G-V) relationship for any of the channels in the presence of toxin. Toxin binding kinetics showed that the association and dissociation rates are consistent with a bimolecular interaction between the peptide and the channel. Based on these, we conclude that Cm28 is not a gating modifier but rather a pore blocker. In a selectivity assay, Cm28 at 150 nM concentration (>100? Kd value for KV1.3) did not inhibit KV1.5, KV11.1, KCa1.1, and KCa3.1 K+ channels; NaV1.5 and NaV1.4 Na+ channels; or the hHV1 H+ channel but blocked ?27% of the KV1.1 current. In a biological functional assay, Cm28 strongly inhibited the expression of the activation markers interleukin-2 receptor and CD40 ligand in anti-CD3?activated human CD4+ effector memory T lymphocytes. Cm28, due to its unique structure, may serve as a template for the generation of novel peptides targeting KV1.3 in autoimmune diseases.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
KV1.2
KV1.3
scorpion toxin
Megjelenés:Journal Of General Physiology. - 154 : 8 (2022), p. 1-18. -
További szerzők:Carcamo-Noriega, Edson Beltrán-Vidal, José Borrego, Jesús Szántó Gábor Tibor (1980-) (vegyész) Zamudio, Fernando Z. Delgado-Prudencio, Gustavo Possani, Lourival Domingos Panyi György (1966-) (biofizikus)
Pályázati támogatás:K143071
OTKA
K142612
OTKA
K132906
OTKA
CONACYT 303045
Egyéb
Tempus Public Foundation
Egyéb
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

12.

001-es BibID:BIBFORM098765
035-os BibID:(cikkazonosító)733610 (scopus)85117131062 (wos)000707249000001
Első szerző:Naseem, Muhammad Umair (biofizikus, molekuláris biológus)
Cím:Optimization of Pichia pastoris Expression System for High-Level Production of Margatoxin / Naseem Muhammad Umair, Tajti Gabor, Gaspar Attila, Szanto Tibor G., Borrego Jesús, Panyi Gyorgy
Dátum:2021
ISSN:1663-9812
Megjegyzések:Margatoxin (MgTx) is a high-affinity blocker of voltage-gated potassium (Kv) channels. It inhibits Kv1.1?Kv1.3 ion channels in picomolar concentrations. This toxin is widely used to study physiological function of Kv ion channels in various cell types, including immune cells. Isolation of native MgTx in large quantities from scorpion venom is not affordable. Chemical synthesis and recombinant production in Escherichia coli need in vitro oxidative refolding for proper disulfide bond formation, resulting in a very low yield of peptide production. The Pichia pastoris expression system offers an economical approach to overcome all these limitations and gives a higher yield of correctly refolded recombinant peptides. In this study, improved heterologous expression of recombinant MgTx (rMgTx) in P. pastoris was obtained by using preferential codons, selecting the hyper-resistant clone against Zeocin, and optimizing the culturing conditions. About 36 ? 4 mg/L of >98% pure His-tagged rMgTx (TrMgTx) was produced, which is a threefold higher yield than has been previously reported. Proteolytic digestion of TrMgTx with factor Xa generated untagged rMgTx (UrMgTx). Both TrMgTx and UrMgTx blocked the Kv1.2 and Kv1.3 currents (patch-clamp) (Kd for Kv1.2 were 64 and 14 pM, and for Kv1.3, 86 and 50 pM, respectively) with comparable potency to the native MgTx. The analysis of the binding kinetics showed that TrMgTx had a lower association rate than UrMgTx for both Kv1.2 and Kv1.3. The dissociation rate of both the analogues was the same for Kv1.3. However, in the case of Kv1.2, TrMgTx showed a much higher dissociation rate with full recovery of the block than UrMgTx. Moreover, in a biological functional assay, both peptides significantly downregulated the expression of early activation markers IL2R and CD40L in activated CD4+ TEM lymphocytes whose activation was Kv1.3 dependent. In conclusion, the authors report that the Pichia expression system is a powerful method to produce disulfide-rich peptides, the overexpression of which could be enhanced noticeably through optimization strategies, making it more cost-effective. Since the presence of the His-tag on rMgTx only mildly altered the block equilibrium and binding kinetics, recombinant toxins could be used in ion channel research without removing the tag and could thus reduce the cost and time demand for toxin production.
Tárgyszavak:Orvostudományok Gyógyszerészeti tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Pichia pastoris
patch-clamp
margatoxin
recombinant expression
Kv1.3 blocker
CD4+ TEM cells
Megjelenés:Frontiers in Pharmacology. - 12 (2021), p. 1-18. -
További szerzők:Tajti Gábor (1988-) (gyógyszerész, biofizikus, sejtbiológus) Gáspár Attila (1970-) (vegyész, kémikus) Szántó Gábor Tibor (1980-) (vegyész) Borrego, Jesús Panyi György (1966-) (biofizikus)
Pályázati támogatás:K119417
OTKA
EFOP-3.6.1-16-2016-00022
EFOP
GINOP2.3.2-15-2016-00044
GINOP
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:
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