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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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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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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
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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
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