1
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Huang YH, Jiang Z, Du Q, Yap K, Bigot A, Kaas Q, Wang CK, Craik DJ. Scanning mutagenesis identifies residues that improve the long-term stability and insecticidal activity of cyclotide kalata B1. J Biol Chem 2024; 300:105682. [PMID: 38272233 PMCID: PMC10877628 DOI: 10.1016/j.jbc.2024.105682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 01/13/2024] [Accepted: 01/17/2024] [Indexed: 01/27/2024] Open
Abstract
Cyclotides are plant-derived disulfide-rich cyclic peptides that have a natural function in plant defense and potential for use as agricultural pesticides. Because of their highly constrained topology, they are highly resistant to thermal, chemical, or enzymatic degradation. However, the stability of cyclotides at alkaline pH for incubation times of longer than a few days is poorly studied but important since these conditions could be encountered in the environment, during storage or field application as insecticides. In this study, kalata B1 (kB1), the prototypical cyclotide, was engineered to improve its long-term stability and retain its insecticidal activity via point mutations. We found that substituting either Asn29 or Gly1 to lysine or leucine increased the stability of kB1 by twofold when incubated in an alkaline buffer (pH = 9.0) for 7 days, while retaining its insecticidal activity. In addition, when Gly1 was replaced with lysine or leucine, the mutants could be cyclized using an asparaginyl endopeptidase, in vitro with a yield of ∼90% within 5 min. These results demonstrate the potential to manufacture kB1 mutants with increased stability and insecticidal activity recombinantly or in planta. Overall, the discovery of mutants of kB1 that have enhanced stability could be useful in leading to longer term activity in the field as bioinsecticides.
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Affiliation(s)
- Yen-Hua Huang
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland, Australia
| | - Zhihao Jiang
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland, Australia
| | - Qingdan Du
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland, Australia
| | - Kuok Yap
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland, Australia
| | | | - Quentin Kaas
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland, Australia
| | - Conan K Wang
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland, Australia
| | - David J Craik
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland, Australia.
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2
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Yano Y, Fukuoka R, Maturana AD, Ohdachi SD, Kita M. Mammalian neurotoxins, Blarina paralytic peptides, cause hyperpolarization of human T-type Ca channel hCa v3.2 activation. J Biol Chem 2023; 299:105066. [PMID: 37468103 PMCID: PMC10493266 DOI: 10.1016/j.jbc.2023.105066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 07/05/2023] [Accepted: 07/14/2023] [Indexed: 07/21/2023] Open
Abstract
Among the rare venomous mammals, the short-tailed shrew Blarina brevicauda has been suggested to produce potent neurotoxins in its saliva to effectively capture prey. Several kallikrein-like lethal proteases have been identified, but the active substances of B. brevicauda remained unclear. Here, we report Blarina paralytic peptides (BPPs) 1 and 2 isolated from its submaxillary glands. Synthetic BPP2 showed mealworm paralysis and a hyperpolarization shift (-11 mV) of a human T-type Ca2+ channel (hCav3.2) activation. The amino acid sequences of BPPs were similar to those of synenkephalins, which are precursors of brain opioid peptide hormones that are highly conserved among mammals. However, BPPs rather resembled centipede neurotoxic peptides SLPTXs in terms of disulfide bond connectivity and stereostructure. Our results suggested that the neurotoxin BPPs were the result of convergent evolution as homologs of nontoxic endogenous peptides that are widely conserved in mammals. This finding is of great interest from the viewpoint of the chemical evolution of vertebrate venoms.
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Affiliation(s)
- Yusuke Yano
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Ryo Fukuoka
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Andres D Maturana
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Satoshi D Ohdachi
- Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan
| | - Masaki Kita
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan.
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3
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Doelman W, Reijnen RC, Dijksman N, Janssen APA, van Driel N, 't Hart BA, Philippens I, Araman C, Baron W, van Kasteren SI. Citrullinated human and murine MOG 35-55 display distinct biophysical and biochemical behavior. J Biol Chem 2023; 299:103065. [PMID: 36841486 PMCID: PMC10060747 DOI: 10.1016/j.jbc.2023.103065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 02/15/2023] [Accepted: 02/18/2023] [Indexed: 02/27/2023] Open
Abstract
The peptide spanning residues 35 to 55 of the protein myelin oligodendrocyte glycoprotein (MOG) has been studied extensively in its role as a key autoantigen in the neuroinflammatory autoimmune disease multiple sclerosis. Rodents and nonhuman primate species immunized with this peptide develop a neuroinflammatory condition called experimental autoimmune encephalomyelitis, often used as a model for multiple sclerosis. Over the last decade, the role of citrullination of this antigen in the disease onset and progression has come under increased scrutiny. We recently reported on the ability of these citrullinated MOG35-55 peptides to aggregate in an amyloid-like fashion, suggesting a new potential pathogenic mechanism underlying this disease. The immunodominant region of MOG is highly conserved between species, with the only difference between the murine and human protein, a polymorphism on position 42, which is serine in mice and proline for humans. Here, we show that the biophysical and biochemical behavior we previously observed for citrullinated murine MOG35-55 is fundamentally different for human and mouse MOG35-55. The citrullinated human peptides do not show amyloid-like behavior under the conditions where the murine peptides do. Moreover, we tested the ability of these peptides to stimulate lymphocytes derived from MOG immunized marmoset monkeys. While the citrullinated murine peptides did not produce a proliferative response, one of the citrullinated human peptides did. We postulate that this unexpected difference is caused by disparate antigen processing. Taken together, our results suggest that further study on the role of citrullination in MOG-induced experimental autoimmune encephalomyelitis is necessary.
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Affiliation(s)
- W Doelman
- Department of Bio-Organic Synthesis, Leiden Institute of Chemistry, Leiden, the Netherlands
| | - R C Reijnen
- Department of Bio-Organic Synthesis, Leiden Institute of Chemistry, Leiden, the Netherlands
| | - N Dijksman
- Section Molecular Neurobiology, Department Biomedical Sciences of Cells & Systems, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - A P A Janssen
- Department of Bio-Organic Synthesis, Leiden Institute of Chemistry, Leiden, the Netherlands
| | - N van Driel
- Department of Immunobiology, Biomedical Primate Research Center, Rijswijk, the Netherlands
| | - B A 't Hart
- Section Molecular Neurobiology, Department Biomedical Sciences of Cells & Systems, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - I Philippens
- Department of Immunobiology, Biomedical Primate Research Center, Rijswijk, the Netherlands
| | - C Araman
- Department of Bio-Organic Synthesis, Leiden Institute of Chemistry, Leiden, the Netherlands
| | - W Baron
- Section Molecular Neurobiology, Department Biomedical Sciences of Cells & Systems, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands.
| | - S I van Kasteren
- Department of Bio-Organic Synthesis, Leiden Institute of Chemistry, Leiden, the Netherlands.
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4
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Viana de Freitas T, Karmakar U, Vasconcelos A, Santos M, Oliveira do Vale Lira B, Costa S, Barbosa E, Cardozo-Fh J, Correa R, Ribeiro DS, Prates M, Magalhães K, Soller Ramada M, Roberto de Souza Almeida Leite J, Bloch C Jr, Lima de Oliveira A, Vendrell M, Brand G. Release of immunomodulatory peptides at bacterial membrane interfaces as a novel strategy to fight microorganisms. J Biol Chem 2023;:103056. [PMID: 36822328 DOI: 10.1016/j.jbc.2023.103056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 02/18/2023] [Accepted: 02/20/2023] [Indexed: 02/23/2023] Open
Abstract
Cationic and amphiphilic peptides can be used as homing devices to accumulate conjugated antibiotics to bacteria-enriched sites and promote efficient microbial killing. However, just as important as tackling bacterial infections, is the modulation of the immune response in this complex microenvironment. In the present report, we designed a peptide chimaera called Chim2, formed by a membrane-active module, an enzyme hydrolysis site, and a formyl peptide receptor 2 (FPR2) agonist. This molecule was designed to adsorb onto bacterial membranes, promote their lysis, and upon hydrolysis by local enzymes, release the FPR2 agonist sequence for activation and recruitment of immune cells. We synthesized the isolated peptide modules of Chim2 and characterized their biological activities independently and as a single polypeptide chain. We conducted antimicrobial assays, along with other tests aiming at the analyses of the cellular and immunological responses. In addition, assays using vesicles as models of eukaryotic and prokaryotic membranes were conducted, and solution structures of Chim2 were generated by 1H NMR. Chim2 is antimicrobial, adsorbs preferentially to negatively charged vesicles while adopting an α-helix structure, and exposes its disorganized tail to the solvent, which facilitates hydrolysis by tryptase-like enzymes, allowing the release of the FPR2 agonist fragment. This fragment was shown to induce accumulation of the cellular activation marker, lipid bodies, in mouse macrophages and the release of immunomodulatory interleukins. In conclusion, these data demonstrate that peptides with antimicrobial and immunomodulatory activities can be considered for further development as drugs.
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5
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Du Q, Huang YH, Wang CK, Kaas Q, Craik DJ. Mutagenesis of bracelet cyclotide hyen D reveals functionally and structurally critical residues for membrane binding and cytotoxicity. J Biol Chem 2022; 298:101822. [PMID: 35283188 PMCID: PMC9006653 DOI: 10.1016/j.jbc.2022.101822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 02/19/2022] [Accepted: 02/21/2022] [Indexed: 11/05/2022] Open
Abstract
Cyclotides have a wide range of bioactivities relevant for agricultural and pharmaceutical applications. This large family of naturally occurring macrocyclic peptides is divided into three subfamilies, with the bracelet subfamily being the largest and comprising the most potent cyclotides reported to date. However, attempts to harness the natural bioactivities of bracelet cyclotides and engineer-optimized analogs have been hindered by a lack of understanding of the structural and functional role of their constituent residues, which has been challenging because bracelet cyclotides are difficult to produce synthetically. We recently established a facile strategy to make the I11L mutant of cyclotide hyen D that is as active as the parent peptide, enabling the subsequent production of a series of variants. In the current study, we report an alanine mutagenesis structure-activity study of [I11L] hyen D to probe the role of individual residues on peptide folding using analytical chromatography, on molecular function using surface plasmon resonance, and on therapeutic potential using cytotoxicity assays. We found that Glu-6 and Thr-15 are critical for maintaining the structure of bracelet cyclotides and that hydrophobic residues in loops 2 and 3 are essential for membrane binding and cytotoxic activity, findings that are distinct from the structural and functional characteristics determined for other cyclotide subfamilies. In conclusion, this is the first report of a mutagenesis scan conducted on a bracelet cyclotide, offering insights into their function and supporting future efforts to engineer bracelet cyclotides for biotechnological applications.
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Affiliation(s)
- Qingdan Du
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD, Australia
| | - Yen-Hua Huang
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD, Australia.
| | - Conan K Wang
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD, Australia
| | - Quentin Kaas
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD, Australia
| | - David J Craik
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD, Australia.
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6
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Smallwood TB, Navarro S, Cristofori-Armstrong B, Watkins TS, Tungatt K, Ryan RYM, Haigh OL, Lutzky VP, Mulvenna JP, Rosengren KJ, Loukas A, Miles JJ, Clark RJ. Synthetic hookworm-derived peptides are potent modulators of primary human immune cell function that protect against experimental colitis in vivo. J Biol Chem 2021; 297:100834. [PMID: 34051231 PMCID: PMC8239465 DOI: 10.1016/j.jbc.2021.100834] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 05/21/2021] [Accepted: 05/25/2021] [Indexed: 12/14/2022] Open
Abstract
The prevalence of autoimmune diseases is on the rise globally. Currently, autoimmunity presents in over 100 different forms and affects around 9% of the world's population. Current treatments available for autoimmune diseases are inadequate, expensive, and tend to focus on symptom management rather than cure. Clinical trials have shown that live helminthic therapy can decrease chronic inflammation associated with inflammatory bowel disease and other gastrointestinal autoimmune inflammatory conditions. As an alternative and better controlled approach to live infection, we have identified and characterized two peptides, Acan1 and Nak1, from the excretory/secretory component of parasitic hookworms for their therapeutic activity on experimental colitis. We synthesized Acan1 and Nak1 peptides from the Ancylostoma caninum and Necator americanus hookworms and assessed their structures and protective properties in human cell-based assays and in a mouse model of acute colitis. Acan1 and Nak1 displayed anticolitic properties via significantly reducing weight loss and colon atrophy, edema, ulceration, and necrosis in 2,4,6-trinitrobenzene sulfonic acid-exposed mice. These hookworm peptides prevented mucosal loss of goblet cells and preserved intestinal architecture. Acan1 upregulated genes responsible for the repair and restitution of ulcerated epithelium, whereas Nak1 downregulated genes responsible for epithelial cell migration and apoptotic cell signaling within the colon. These peptides were nontoxic and displayed key immunomodulatory functions in human peripheral blood mononuclear cells by suppressing CD4+ T cell proliferation and inhibiting IL-2 and TNF production. We conclude that Acan1 and Nak1 warrant further development as therapeutics for the treatment of autoimmunity, particularly gastrointestinal inflammatory conditions.
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Affiliation(s)
- Taylor B Smallwood
- Faculty of Medicine, School of Biomedical Sciences, The University of Queensland, QLD, Australia
| | - Severine Navarro
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia; The Australian Institute of Tropical Health and Medicine, James Cook University, QLD, Australia; Woolworths Centre for Child Nutrition Research, Institute of Health and Biomedical Innovation, Queensland University of Technology, QLD, Australia
| | - Ben Cristofori-Armstrong
- Faculty of Medicine, School of Biomedical Sciences, The University of Queensland, QLD, Australia
| | - Thomas S Watkins
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia; Centre for Molecular Therapeutics, The Australian Institute of Tropical Health and Medicine, James Cook University, QLD, Australia
| | - Katie Tungatt
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia; Centre for Molecular Therapeutics, The Australian Institute of Tropical Health and Medicine, James Cook University, QLD, Australia; Centre for Tropical Bioinformatics and Molecular Biology, James Cook University, QLD, Australia
| | - Rachael Y M Ryan
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia; The Australian Institute of Tropical Health and Medicine, James Cook University, QLD, Australia; Centre for Molecular Therapeutics, The Australian Institute of Tropical Health and Medicine, James Cook University, QLD, Australia
| | - Oscar L Haigh
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Viviana P Lutzky
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Jason P Mulvenna
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - K Johan Rosengren
- Faculty of Medicine, School of Biomedical Sciences, The University of Queensland, QLD, Australia
| | - Alex Loukas
- Centre for Molecular Therapeutics, The Australian Institute of Tropical Health and Medicine, James Cook University, QLD, Australia
| | - John J Miles
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia; The Australian Institute of Tropical Health and Medicine, James Cook University, QLD, Australia; Centre for Molecular Therapeutics, The Australian Institute of Tropical Health and Medicine, James Cook University, QLD, Australia; Centre for Tropical Bioinformatics and Molecular Biology, James Cook University, QLD, Australia; Institute of Infection and Immunity, Cardiff University School of Medicine, University Hospital, Cardiff, Wales, United Kingdom.
| | - Richard J Clark
- Faculty of Medicine, School of Biomedical Sciences, The University of Queensland, QLD, Australia.
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7
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Chavali SS, Mali SM, Jenkins JL, Fasan R, Wedekind JE. Co-crystal structures of HIV TAR RNA bound to lab-evolved proteins show key roles for arginine relevant to the design of cyclic peptide TAR inhibitors. J Biol Chem 2020; 295:16470-16486. [PMID: 33051202 PMCID: PMC7864049 DOI: 10.1074/jbc.ra120.015444] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/24/2020] [Indexed: 01/28/2023] Open
Abstract
RNA-protein interfaces control key replication events during the HIV-1 life cycle. The viral trans-activator of transcription (Tat) protein uses an archetypal arginine-rich motif (ARM) to recruit the host positive transcription elongation factor b (pTEFb) complex onto the viral trans-activation response (TAR) RNA, leading to activation of HIV transcription. Efforts to block this interaction have stimulated production of biologics designed to disrupt this essential RNA-protein interface. Here, we present four co-crystal structures of lab-evolved TAR-binding proteins (TBPs) in complex with HIV-1 TAR. Our results reveal that high-affinity binding requires a distinct sequence and spacing of arginines within a specific β2-β3 hairpin loop that arose during selection. Although loops with as many as five arginines were analyzed, only three arginines could bind simultaneously with major-groove guanines. Amino acids that promote backbone interactions within the β2-β3 loop were also observed to be important for high-affinity interactions. Based on structural and affinity analyses, we designed two cyclic peptide mimics of the TAR-binding β2-β3 loop sequences present in two high-affinity TBPs (KD values of 4.2 ± 0.3 and 3.0 ± 0.3 nm). Our efforts yielded low-molecular weight compounds that bind TAR with low micromolar affinity (KD values ranging from 3.6 to 22 μm). Significantly, one cyclic compound within this series blocked binding of the Tat-ARM peptide to TAR in solution assays, whereas its linear counterpart did not. Overall, this work provides insight into protein-mediated TAR recognition and lays the ground for the development of cyclic peptide inhibitors of a vital HIV-1 RNA-protein interaction.
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Affiliation(s)
- Sai Shashank Chavali
- Department of Biochemistry and Biophysics and Center for RNA Biology, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - Sachitanand M Mali
- Department of Chemistry, University of Rochester, Rochester, New York, USA
| | - Jermaine L Jenkins
- Department of Biochemistry and Biophysics and Center for RNA Biology, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - Rudi Fasan
- Department of Chemistry, University of Rochester, Rochester, New York, USA
| | - Joseph E Wedekind
- Department of Biochemistry and Biophysics and Center for RNA Biology, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA.
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8
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Wang CK, Amiss AS, Weidmann J, Craik DJ. Structure-activity analysis of truncated albumin-binding domains suggests new lead constructs for potential therapeutic delivery. J Biol Chem 2020; 295:12143-12152. [PMID: 32647013 PMCID: PMC7443490 DOI: 10.1074/jbc.ra120.014168] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 07/09/2020] [Indexed: 12/13/2022] Open
Abstract
Rapid clearance by renal filtration is a major impediment to the translation of small bioactive biologics into drugs. To extend serum t1/2, a commonly used approach is to attach drug leads to the G-related albumin-binding domain (ABD) to bind albumin and evade clearance. Despite the success of this approach in extending half-lives of a wide range of biologics, it is unclear whether the existing constructs are optimized for binding and size; any improvements along these lines could lead to improved drugs. Characterization of the biophysics of binding of an ABD to albumin in solution could shed light on this question. Here, we examine the binding of an ABD to human serum albumin using isothermal titration calorimetry and assess the structural integrity of the ABD using CD, NMR, and molecular dynamics. A structure-activity analysis of truncations of the ABD suggests that downsized variants could replace the full-length domain. Reducing size could have the benefit of reducing potential immunogenicity problems. We further showed that one of these variants could be used to design a bifunctional molecule with affinity for albumin and a serum protein involved in cholesterol metabolism, PCSK9, demonstrating the potential utility of these fragments in the design of cholesterol-lowering drugs. Future work could extend these in vitro binding studies to other ABD variants to develop therapeutics. Our study presents new understanding of the solution structural and binding properties of ABDs, which has implications for the design of next-generation long-lasting therapeutics.
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Affiliation(s)
- Conan K. Wang
- Institute for Molecular Bioscience and Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland, Australia
| | - Anna S. Amiss
- Institute for Molecular Bioscience and Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland, Australia
| | - Joachim Weidmann
- Institute for Molecular Bioscience and Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland, Australia
| | - David J. Craik
- Institute for Molecular Bioscience and Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland, Australia
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9
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Du Q, Chan LY, Gilding EK, Henriques ST, Condon ND, Ravipati AS, Kaas Q, Huang YH, Craik DJ. Discovery and mechanistic studies of cytotoxic cyclotides from the medicinal herb Hybanthus enneaspermus. J Biol Chem 2020; 295:10911-10925. [PMID: 32414842 DOI: 10.1074/jbc.ra120.012627] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 05/08/2020] [Indexed: 12/12/2022] Open
Abstract
Cyclotides are plant-derived peptides characterized by an ∼30-amino acid-long cyclic backbone and a cystine knot motif. Cyclotides have diverse bioactivities, and their cytotoxicity has attracted significant attention for its potential anticancer applications. Hybanthus enneaspermus (Linn) F. Muell is a medicinal herb widely used in India as a libido enhancer, and a previous study has reported that it may contain cyclotides. In the current study, we isolated 11 novel cyclotides and 1 known cyclotide (cycloviolacin O2) from H. enneaspermus and used tandem MS to determine their amino acid sequences. We found that among these cyclotides, hyen C comprises a unique sequence in loops 1, 2, 3, 4, and 6 compared with known cyclotides. The most abundant cyclotide in this plant, hyen D, had anticancer activity comparable to that of cycloviolacin O2, one of the most cytotoxic known cyclotides. We also provide mechanistic insights into how these novel cyclotides interact with and permeabilize cell membranes. Results from surface plasmon resonance experiments revealed that hyen D, E, L, and M and cycloviolacin O2 preferentially interact with model lipid membranes that contain phospholipids with phosphatidyl-ethanolamine headgroups. The results of a lactate dehydrogenase assay indicated that exposure to these cyclotides compromises cell membrane integrity. Using live-cell imaging, we show that hyen D induces rapid membrane blebbing and cell necrosis. Cyclotide-membrane interactions correlated with the observed cytotoxicity, suggesting that membrane permeabilization and disintegration underpin cyclotide cytotoxicity. These findings broaden our knowledge on the indigenous Indian herb H. enneaspermus and have uncovered cyclotides with potential anticancer activity.
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Affiliation(s)
- Qingdan Du
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Lai Y Chan
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Edward K Gilding
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Sónia Troeira Henriques
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia.,School of Biomedical Sciences, Institute of Health & Biomedical Innovation and Translational Research Institute, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Nicholas D Condon
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Anjaneya S Ravipati
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Quentin Kaas
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Yen-Hua Huang
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - David J Craik
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
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10
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Kam A, Loo S, Fan JS, Sze SK, Yang D, Tam JP. Roseltide rT7 is a disulfide-rich, anionic, and cell-penetrating peptide that inhibits proteasomal degradation. J Biol Chem 2019; 294:19604-19615. [PMID: 31727740 DOI: 10.1074/jbc.ra119.010796] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 11/02/2019] [Indexed: 12/21/2022] Open
Abstract
Disulfide-rich plant peptides with molecular masses of 2-6 kDa represent an expanding class of peptidyl-type natural products with diverse functions. They are structurally compact, hyperstable, and underexplored as cell-penetrating agents that inhibit intracellular functions. Here, we report the discovery of an anionic, 34-residue peptide, the disulfide-rich roseltide rT7 from Hibiscus sabdariffa (of the Malvaceae family) that penetrates cells and inhibits their proteasomal activities. Combined proteomics and NMR spectroscopy revealed that roseltide rT7 is a cystine-knotted, six-cysteine hevein-like cysteine-rich peptide. A pair-wise comparison indicated that roseltide rT7 is >100-fold more stable against protease degradation than its S-alkylated analog. Confocal microscopy studies and cell-based assays disclosed that after roseltide rT7 penetrates cells, it causes accumulation of ubiquitinated proteins, inhibits human 20S proteasomes, reduces tumor necrosis factor-induced IκBα degradation, and decreases expression levels of intercellular adhesion molecule-1. Structure-activity studies revealed that roseltide rT7 uses a canonical substrate-binding mechanism for proteasomal inhibition enabled by an IIML motif embedded in its proline-rich and exceptionally long intercysteine loop 4. Taken together, our results provide mechanistic insights into a novel disulfide-rich, anionic, and cell-penetrating peptide, representing a potential lead for further development as a proteasomal inhibitor in anti-cancer or anti-inflammatory therapies.
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Affiliation(s)
- Antony Kam
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Shining Loo
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Jing-Song Fan
- Department of Biological Sciences, National University of Singapore, Singapore 117543
| | - Siu Kwan Sze
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
| | - Daiwen Yang
- Department of Biological Sciences, National University of Singapore, Singapore 117543
| | - James P Tam
- School of Biological Sciences, Nanyang Technological University, Singapore 637551
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11
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Abstract
Since the discovery of vancomycin in the 1950s, the glycopeptide antibiotics (GPAs) have been of great interest to the scientific community. These nonribosomally biosynthesized peptides are highly cross-linked, often glycosylated, and inhibit bacterial cell wall assembly by interfering with peptidoglycan synthesis. Interest in glycopeptide antibiotics covers many scientific disciplines, due to their challenging total syntheses, complex biosynthesis pathways, mechanism of action, and high potency. After intense efforts, early enthusiasm has given way to a recognition of the challenges in chemically synthesizing GPAs and of the effort needed to study and modify GPA-producing strains to prepare new GPAs to address the increasing threat of microbial antibiotic resistance. Although the preparation of GPAs, either by modifying the pendant groups such as saccharides or by functionalizing the N- or C-terminal moieties, is readily achievable, the peptide core of these molecules-the GPA aglycone-remains highly challenging to modify. This review aims to present a summary of the results of GPA modification obtained with the three major approaches developed to date: in vivo strain manipulation, total chemical synthesis, and chemoenzymatic synthesis methods.
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Affiliation(s)
- Edward Marschall
- The Monash Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia; EMBL Australia, Monash University, Clayton, Victoria 3800, Australia
| | - Max J Cryle
- The Monash Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia; EMBL Australia, Monash University, Clayton, Victoria 3800, Australia.
| | - Julien Tailhades
- The Monash Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia; EMBL Australia, Monash University, Clayton, Victoria 3800, Australia.
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12
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Botta J, Bibic L, Killoran P, McCormick PJ, Howell LA. Design and development of stapled transmembrane peptides that disrupt the activity of G-protein-coupled receptor oligomers. J Biol Chem 2019; 294:16587-16603. [PMID: 31467080 PMCID: PMC6851324 DOI: 10.1074/jbc.ra119.009160] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 08/08/2019] [Indexed: 12/23/2022] Open
Abstract
Membrane proteins can associate into larger complexes. Examples include receptor tyrosine complexes, ion channels, transporters, and G protein–coupled receptors (GPCRs). For the latter, there is abundant evidence indicating that GPCRs assemble into complexes, through both homo- and heterodimerization. However, the tools for studying and disrupting these complexes, GPCR or otherwise, are limited. Here, we have developed stabilized interference peptides for this purpose. We have previously reported that tetrahydrocannabinol-mediated cognitive impairment arises from homo- or heterooligomerization between the GPCRs cannabinoid receptor type 1 (CB1R) and 5-hydroxytryptamine 2A (5-HT2AR) receptors. Here, to disrupt this interaction through targeting CB1–5-HT2A receptor heteromers in HEK293 cells and using an array of biochemical techniques, including calcium and cAMP measurements, bimolecular fluorescence complementation assays, and CD-based helicity assessments, we developed a NanoLuc binary technology (NanoBiT)-based reporter assay to screen a small library of aryl-carbon–stapled transmembrane-mimicking peptides produced by solid-phase peptide synthesis. We found that these stapling peptides have increased α-helicity and improved proteolytic resistance without any loss of disrupting activity in vitro, suggesting that this approach may also have utility in vivo. In summary, our results provide proof of concept for using NanoBiT to study membrane protein complexes and for stabilizing disrupting peptides to target such membrane complexes through hydrocarbon-mediated stapling. We propose that these peptides could be developed to target previously undruggable GPCR heteromers.
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Affiliation(s)
- Joaquín Botta
- Centre for Endocrinology, William Harvey Research Institute, Bart's and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, United Kingdom.,School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Lucka Bibic
- School of Pharmacy, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom
| | - Patrick Killoran
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, James Parsons Building, Byrom Street, Liverpool L3 3AF, United Kingdom
| | - Peter J McCormick
- Centre for Endocrinology, William Harvey Research Institute, Bart's and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, United Kingdom
| | - Lesley A Howell
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, United Kingdom
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13
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Denisov SS, Ippel JH, Heinzmann ACA, Koenen RR, Ortega-Gomez A, Soehnlein O, Hackeng TM, Dijkgraaf I. Tick saliva protein Evasin-3 modulates chemotaxis by disrupting CXCL8 interactions with glycosaminoglycans and CXCR2. J Biol Chem 2019; 294:12370-12379. [PMID: 31235521 PMCID: PMC6699855 DOI: 10.1074/jbc.ra119.008902] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 06/11/2019] [Indexed: 01/22/2023] Open
Abstract
Chemokines are a group of chemotaxis proteins that regulate cell trafficking and play important roles in immune responses and inflammation. Ticks are blood-sucking parasites that secrete numerous immune-modulatory agents in their saliva to evade host immune responses. Evasin-3 is a small salivary protein that belongs to a class of chemokine-binding proteins isolated from the brown dog tick, Rhipicephalus sanguineus. Evasin-3 has been shown to have a high affinity for chemokines CXCL1 and CXCL8 and to diminish inflammation in mice. In the present study, solution NMR spectroscopy was used to investigate the structure of Evasin-3 and its CXCL8–Evasin-3 complex. Evasin-3 is found to disrupt the glycosaminoglycan-binding site of CXCL8 and inhibit the interaction of CXCL8 with CXCR2. Structural data were used to design two novel CXCL8-binding peptides. The linear tEv3 17–56 and cyclic tcEv3 16–56 dPG Evasin-3 variants were chemically synthesized by solid-phase peptide synthesis. The affinity of these newly synthesized variants to CXCL8 was measured by surface plasmon resonance biosensor analysis. The Kd values of tEv3 17–56 and tcEv3 16–56 dPG were 27 and 13 nm, respectively. Both compounds effectively inhibited CXCL8-induced migration of polymorphonuclear neutrophils. The present results suggest utility of synthetic Evasin-3 variants as scaffolds for designing and fine-tuning new chemokine-binding agents that suppress immune responses and inflammation.
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Affiliation(s)
- Stepan S Denisov
- Department of Biochemistry, University of Maastricht, Cardiovascular Research Institute Maastricht, 6229 ER, Maastricht, The Netherlands
| | - Johannes H Ippel
- Department of Biochemistry, University of Maastricht, Cardiovascular Research Institute Maastricht, 6229 ER, Maastricht, The Netherlands
| | - Alexandra C A Heinzmann
- Department of Biochemistry, University of Maastricht, Cardiovascular Research Institute Maastricht, 6229 ER, Maastricht, The Netherlands
| | - Rory R Koenen
- Department of Biochemistry, University of Maastricht, Cardiovascular Research Institute Maastricht, 6229 ER, Maastricht, The Netherlands
| | - Almudena Ortega-Gomez
- Institute for Cardiovascular Prevention, Ludwig Maximilian University, 80336, Munich, Germany
| | - Oliver Soehnlein
- Institute for Cardiovascular Prevention, Ludwig Maximilian University, 80336, Munich, Germany; German Center for Cardiovascular Research, 13316, Berlin, Germany; Partner Site Munich Heart Alliance, 80802 Munich, Germany; Department of Physiology and Pharmacology and Department of Medicine, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Tilman M Hackeng
- Department of Biochemistry, University of Maastricht, Cardiovascular Research Institute Maastricht, 6229 ER, Maastricht, The Netherlands
| | - Ingrid Dijkgraaf
- Department of Biochemistry, University of Maastricht, Cardiovascular Research Institute Maastricht, 6229 ER, Maastricht, The Netherlands.
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14
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Kebe NM, Samanta K, Singh P, Lai-Kee-Him J, Apicella V, Payrot N, Lauraire N, Legrand B, Lisowski V, Mbang-Benet DE, Pages M, Bastien P, Kajava AV, Bron P, Hernandez JF, Coux O. The HslV Protease from Leishmania major and Its Activation by C-terminal HslU Peptides. Int J Mol Sci 2019; 20:E1021. [PMID: 30813632 DOI: 10.3390/ijms20051021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 02/11/2019] [Accepted: 02/20/2019] [Indexed: 12/31/2022] Open
Abstract
HslVU is an ATP-dependent proteolytic complex present in certain bacteria and in the mitochondrion of some primordial eukaryotes, including deadly parasites such as Leishmania. It is formed by the dodecameric protease HslV and the hexameric ATPase HslU, which binds via the C-terminal end of its subunits to HslV and activates it by a yet unclear allosteric mechanism. We undertook the characterization of HslV from Leishmania major (LmHslV), a trypanosomatid that expresses two isoforms for HslU, LmHslU1 and LmHslU2. Using a novel and sensitive peptide substrate, we found that LmHslV can be activated by peptides derived from the C-termini of both LmHslU1 and LmHslU2. Truncations, Ala- and D-scans of the C-terminal dodecapeptide of LmHslU2 (LmC12-U2) showed that five out of the six C-terminal residues of LmHslU2 are essential for binding to and activating HslV. Peptide cyclisation with a lactam bridge allowed shortening of the peptide without loss of potency. Finally, we found that dodecapeptides derived from HslU of other parasites and bacteria are able to activate LmHslV with similar or even higher efficiency. Importantly, using electron microscopy approaches, we observed that the activation of LmHslV was accompanied by a large conformational remodeling, which represents a yet unidentified layer of control of HslV activation.
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15
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Kam A, Loo S, Dutta B, Sze SK, Tam JP. Plant-derived mitochondria-targeting cysteine-rich peptide modulates cellular bioenergetics. J Biol Chem 2019; 294:4000-4011. [PMID: 30674551 DOI: 10.1074/jbc.ra118.006693] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Revised: 01/07/2019] [Indexed: 12/16/2022] Open
Abstract
Mitochondria are attractive therapeutic targets for developing agents to delay age-related frailty and diseases. However, few promising leads have been identified from natural products. Previously, we identified roseltide rT1, a hyperstable 27-residue cysteine-rich peptide from Hibiscus sabdariffa, as a knottin-type neutrophil elastase inhibitor. Here, we show that roseltide rT1 is also a cell-penetrating, mitochondria-targeting peptide that increases ATP production. Results from flow cytometry, live-cell imaging, pulldown assays, and genetically-modified cell lines supported that roseltide rT1 enters cells via glycosaminoglycan-dependent endocytosis, and enters the mitochondria through TOM20, a mitochondrial protein import receptor. We further showed that roseltide rT1 increases cellular ATP production via mitochondrial membrane hyperpolarization. Using biotinylated roseltide rT1 for target identification and proteomic analysis, we showed that human mitochondrial membrane ATP synthase subunit O is an intramitochondrial target. Collectively, these data support our discovery that roseltide rT1 is a first-in-class mitochondria-targeting, cysteine-rich peptide with potentials to be developed into tools to further our understanding of mitochrondria-related diseases.
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Affiliation(s)
- Antony Kam
- From the School of Biological Sciences, Nanyang Technological University, 637551 Singapore
| | - Shining Loo
- From the School of Biological Sciences, Nanyang Technological University, 637551 Singapore
| | - Bamaprasad Dutta
- From the School of Biological Sciences, Nanyang Technological University, 637551 Singapore
| | - Siu Kwan Sze
- From the School of Biological Sciences, Nanyang Technological University, 637551 Singapore
| | - James P Tam
- From the School of Biological Sciences, Nanyang Technological University, 637551 Singapore
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16
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Paolini-Bertrand M, Cerini F, Martins E, Scurci I, Hartley O. Rapid and low-cost multiplex synthesis of chemokine analogs. J Biol Chem 2018; 293:19092-19100. [PMID: 30305389 DOI: 10.1074/jbc.ra118.004370] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 09/25/2018] [Indexed: 11/06/2022] Open
Abstract
Peptides represent a promising source of new medicines, but improved technologies are needed to facilitate discovery and optimization campaigns. In particular, longer peptides with multiple disulfide bridges are challenging to produce, and producing large numbers of structurally related variants is dissuasively costly and time-consuming. The principal cost and time drivers are the multiple column chromatography purification steps that are used during the multistep chemical synthesis procedure, which involves both ligation and oxidative refolding steps. In this study, we developed a method for multiplex parallel synthesis of complex peptide analogs in which the structurally variant region of the molecule is produced as a small peptide on a 384-well synthesizer with subsequent ligation to the longer, structurally invariant region and oxidative refolding carried out in-well without any column purification steps. To test the method, we used a panel of 96 analogs of the chemokine RANTES (regulated on activation normal T cell expressed and secreted)/CCL5 (69 residues, two disulfide bridges), which had been synthesized using standard approaches and characterized pharmacologically in an earlier study. Although, as expected, the multiplex method generated chemokine analogs of lower purity than those produced in the original study, it was nonetheless possible to closely match the pharmacological attributes (anti-HIV potency, capacity to elicit G protein signaling, and capacity to elicit intracellular receptor sequestration) of each chemokine analog to reference data from the earlier study. This rapid, low-cost approach has the potential to support discovery and optimization campaigns based on analogs of other chemokines as well as those of other complex peptide and small protein targets of a similar size.
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Affiliation(s)
- Marianne Paolini-Bertrand
- From the Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, 1211 Geneva 4, Switzerland
| | - Fabrice Cerini
- From the Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, 1211 Geneva 4, Switzerland
| | - Elsa Martins
- From the Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, 1211 Geneva 4, Switzerland
| | - Ilaria Scurci
- From the Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, 1211 Geneva 4, Switzerland
| | - Oliver Hartley
- From the Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, 1 rue Michel Servet, 1211 Geneva 4, Switzerland
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17
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Sayeed M, Gautam S, Verma DP, Afshan T, Kumari T, Srivastava AK, Ghosh JK. A collagen domain-derived short adiponectin peptide activates APPL1 and AMPK signaling pathways and improves glucose and fatty acid metabolisms. J Biol Chem 2018; 293:13509-13523. [PMID: 29991592 DOI: 10.1074/jbc.ra118.001801] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 07/02/2018] [Indexed: 12/13/2022] Open
Abstract
Adiponectin is a fat tissue-derived adipokine with beneficial effects against diabetes, cardiovascular diseases, and cancer. Accordingly, adiponectin-mimetic molecules possess significant pharmacological potential. Oligomeric states of adiponectin appear to determine its biological activity. We identified a highly conserved, 13-residue segment (ADP-1) from adiponectin's collagen domain, which comprises GXXG motifs and has one asparagine and two histidine residues that assist in oligomeric protein assembly. We therefore hypothesized that ADP-1 promotes oligomeric assembly and thereby mediates potential metabolic effects. We observed here that ADP-1 is stable in human serum and oligomerizes in aqueous environments. We also found that ADP-1 activates AMP-activated protein kinase (AMPK) in an adaptor protein, phosphotyrosine interacting with PH domain and leucine zipper 1 (APPL1)-dependent pathway and stimulates glucose uptake in rat skeletal muscle cells (L6 myotubes). ADP-1-induced glucose transport coincided with ADP-1-induced biosynthesis of glucose transporter 4 and its translocation to the plasma membrane. ADP-1 induced an interaction between APPL1 and the small GTPase Rab5, resulting in AMPK phosphorylation, in turn leading to phosphorylation of p38 mitogen-activated protein kinase (MAPK), acetyl-CoA carboxylase, and peroxisome proliferator-activated receptor α. Similar to adiponectin, ADP-1 increased the expression of the adiponectin receptor 1 (AdipoR1) gene. Of note, ADP-1 decreased blood glucose levels and enhanced insulin production in pancreatic β cells in db/db mice. Further, ADP-1 beneficially affected lipid metabolism by enhancing lipid globule formation in mouse 3T3-L1 adipocytes. To our knowledge, this is the first report on identification of a short peptide from adiponectin with positive effects on glucose or fatty acid metabolism.
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Affiliation(s)
- Mohd Sayeed
- From the Molecular and Structural Biology Division and
| | - Sudeep Gautam
- the Biochemistry Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow-226 031, India
| | | | | | - Tripti Kumari
- From the Molecular and Structural Biology Division and
| | - Arvind Kumar Srivastava
- the Biochemistry Division, CSIR-Central Drug Research Institute, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow-226 031, India
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18
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Wu X, Huang YH, Kaas Q, Harvey PJ, Wang CK, Tae HS, Adams DJ, Craik DJ. Backbone cyclization of analgesic conotoxin GeXIVA facilitates direct folding of the ribbon isomer. J Biol Chem 2017; 292:17101-17112. [PMID: 28851841 DOI: 10.1074/jbc.m117.808386] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Indexed: 12/20/2022] Open
Abstract
Conotoxin GeXIVA inhibits the α9α10 nicotinic acetylcholine receptor (nAChR) and is analgesic in animal models of pain. α-Conotoxins have four cysteines that can have three possible disulfide connectivities: globular (CysI-CysIII and CysII-CysIV), ribbon (CysI-CysIV and CysII-CysIII), or bead (CysI-CysII and CysIII-CysIV). Native α-conotoxins preferably adopt the globular connectivity, and previous studies of α-conotoxins have focused on the globular isomers as the ribbon and bead isomers typically have lower potency at nAChRs than the globular form. A recent report showed that the bead and ribbon isomers of GeXIVA are more potent than the globular isomer, with low nanomolar half-maximal inhibitory concentrations (IC50). Despite this high potency, the therapeutic potential of GeXIVA is limited, because like most peptides, it is susceptible to proteolytic degradation and is challenging to synthesize in high yield. Here we used backbone cyclization as a strategy to improve the folding yield as well as increase the serum stability of ribbon GeXIVA while preserving activity at the α9α10 nAChR. Specifically, cyclization of ribbon GeXIVA with a two-residue linker maintained the biological activity at the human α9α10 nAChR and improved stability in human serum. Short linkers led to selective formation of the ribbon disulfide isomer without requiring orthogonal protection. Overall, this study highlights the value of backbone cyclization in directing folding, improving yields, and stabilizing conotoxins with therapeutic potential.
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Affiliation(s)
- Xiaosa Wu
- From the Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia and
| | - Yen-Hua Huang
- From the Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia and
| | - Quentin Kaas
- From the Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia and
| | - Peta J Harvey
- From the Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia and
| | - Conan K Wang
- From the Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia and
| | - Han-Shen Tae
- the Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - David J Adams
- the Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - David J Craik
- From the Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia and
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19
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Cobos Caceres C, Bansal PS, Navarro S, Wilson D, Don L, Giacomin P, Loukas A, Daly NL. An engineered cyclic peptide alleviates symptoms of inflammation in a murine model of inflammatory bowel disease. J Biol Chem 2017; 292:10288-10294. [PMID: 28473469 PMCID: PMC5473231 DOI: 10.1074/jbc.m117.779215] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 04/20/2017] [Indexed: 12/11/2022] Open
Abstract
Inflammatory bowel diseases (IBDs) are a set of complex and debilitating diseases for which there is no satisfactory treatment. Recent studies have shown that small peptides show promise for reducing inflammation in models of IBD. However, these small peptides are likely to be unstable and rapidly cleared from the circulation, and therefore, if not modified for better stability, represent non-viable drug leads. We hypothesized that improving the stability of these peptides by grafting them into a stable cyclic peptide scaffold may enhance their therapeutic potential. Using this approach, we have designed a novel cyclic peptide that comprises a small bioactive peptide from the annexin A1 protein grafted into a sunflower trypsin inhibitor cyclic scaffold. We used native chemical ligation to synthesize the grafted cyclic peptide. This engineered cyclic peptide maintained the overall fold of the naturally occurring cyclic peptide, was more effective at reducing inflammation in a mouse model of acute colitis than the bioactive peptide alone, and showed enhanced stability in human serum. Our findings suggest that the use of cyclic peptides as structural backbones offers a promising approach for the treatment of IBD and potentially other chronic inflammatory conditions.
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MESH Headings
- Animals
- Anti-Inflammatory Agents, Non-Steroidal/chemistry
- Anti-Inflammatory Agents, Non-Steroidal/metabolism
- Anti-Inflammatory Agents, Non-Steroidal/therapeutic use
- Colitis, Ulcerative/drug therapy
- Colitis, Ulcerative/immunology
- Colitis, Ulcerative/pathology
- Colon/drug effects
- Colon/immunology
- Colon/pathology
- Disease Models, Animal
- Drug Design
- Drug Stability
- Gastrointestinal Agents/chemical synthesis
- Gastrointestinal Agents/chemistry
- Gastrointestinal Agents/therapeutic use
- Humans
- Male
- Mice, Inbred C57BL
- Models, Molecular
- Organ Size/drug effects
- Peptides, Cyclic/chemistry
- Peptides, Cyclic/metabolism
- Peptides, Cyclic/therapeutic use
- Protein Conformation
- Protein Engineering
- Protein Folding
- Protein Stability
- Proteolysis
- Random Allocation
- Serum/enzymology
- Specific Pathogen-Free Organisms
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Affiliation(s)
- Claudia Cobos Caceres
- From the Centre for Biodiscovery and Molecular Development of Therapeutics, AITHM, James Cook University, Cairns, Queensland 4870, Australia
| | - Paramjit S Bansal
- From the Centre for Biodiscovery and Molecular Development of Therapeutics, AITHM, James Cook University, Cairns, Queensland 4870, Australia
| | - Severine Navarro
- From the Centre for Biodiscovery and Molecular Development of Therapeutics, AITHM, James Cook University, Cairns, Queensland 4870, Australia
| | - David Wilson
- From the Centre for Biodiscovery and Molecular Development of Therapeutics, AITHM, James Cook University, Cairns, Queensland 4870, Australia
| | - Laurianne Don
- From the Centre for Biodiscovery and Molecular Development of Therapeutics, AITHM, James Cook University, Cairns, Queensland 4870, Australia
| | - Paul Giacomin
- From the Centre for Biodiscovery and Molecular Development of Therapeutics, AITHM, James Cook University, Cairns, Queensland 4870, Australia
| | - Alex Loukas
- From the Centre for Biodiscovery and Molecular Development of Therapeutics, AITHM, James Cook University, Cairns, Queensland 4870, Australia
| | - Norelle L Daly
- From the Centre for Biodiscovery and Molecular Development of Therapeutics, AITHM, James Cook University, Cairns, Queensland 4870, Australia
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20
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Dang B, Chhabra S, Pennington MW, Norton RS, Kent SBH. Reinvestigation of the biological activity of d-allo-ShK protein. J Biol Chem 2017; 292:12599-12605. [PMID: 28596383 DOI: 10.1074/jbc.m117.793943] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 06/04/2017] [Indexed: 11/06/2022] Open
Abstract
ShK toxin from the sea anemone Stichodactyla helianthus is a 35-residue protein that binds to the Kv1.3 ion channel with high affinity. Recently we determined the X-ray structure of ShK toxin by racemic crystallography, in the course of which we discovered that d-ShK has a near-background IC50 value ∼50,000 times lower than that of the l-ShK toxin. This lack of activity was at odds with previously reported results for an ShK diastereomer designated d-allo-ShK, for which significant biological activity had been observed in a similar receptor-blocking assay. As reported, d-allo-ShK was made up of d-amino acids, but with retention of the natural stereochemistry of the chiral side chains of the Ile and Thr residues, i.e. containing d-allo-Ile and d-allo-Thr along with d-amino acids and glycine. To understand its apparent biological activity, we set out to chemically synthesize d-allo-ShK and determine its X-ray structure by racemic crystallography. Using validated allo-Thr and allo-Ile, both l-allo-ShK and d-allo-ShK polypeptide chains were prepared by total chemical synthesis. Neither the l-allo-ShK nor the d-allo-ShK polypeptides folded, whereas both l-ShK and d-ShK folded smoothly under the same conditions. Re-examination of NMR spectra of the previously reported d-allo-ShK protein revealed that diagnostic Thr and Ile signals were the same as for authentic d-ShK. On the basis of these results, we conclude that the previously reported d-allo-ShK was in fact d-ShK, the true enantiomer of natural l-ShK toxin, and that the apparent biological activity may have arisen from inadvertent contamination with trace amounts of l-ShK toxin.
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Affiliation(s)
- Bobo Dang
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637.
| | - Sandeep Chhabra
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | | | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Stephen B H Kent
- Department of Chemistry, University of Chicago, Chicago, Illinois 60637
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21
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Najjar K, Erazo-Oliveras A, Brock DJ, Wang TY, Pellois JP. An l- to d-Amino Acid Conversion in an Endosomolytic Analog of the Cell-penetrating Peptide TAT Influences Proteolytic Stability, Endocytic Uptake, and Endosomal Escape. J Biol Chem 2016; 292:847-861. [PMID: 27923812 DOI: 10.1074/jbc.m116.759837] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 12/05/2016] [Indexed: 12/12/2022] Open
Abstract
Cell-penetrating peptides (CPPs) are well established as delivery agents for otherwise cell-impermeable cargos. CPPs can also theoretically be used to modulate intracellular processes. However, their susceptibility to proteolytic degradation often limits their utility in these applications. Previous studies have explored the consequences for cellular uptake of converting the residues in CPPs from l- to d-stereochemistry, but conflicting results have been reported and specific steps en route to intracellular activity have not been explored. Here we use dimeric fluorescence TAT as a model CPP to explore the broader consequences of l- to d-stereochemical conversion. We show that inversion of chirality provides protease resistance without altering the overall mode of cellular entry, a process involving endocytic uptake followed by endosomal escape and cytosolic access. However, whereas inversion of chirality reduces endocytic uptake, the d-peptide, once in the endosome, is significantly more prone to escape than its l-counterpart. Moreover, the d-peptide is retained in the cytosol of cells for several days, whereas the l-peptide is degraded within hours. Notably, while the l-peptide is relatively innocuous to cells, the d-peptide exerts a prolonged anti-proliferative activity. Together, our results establish connections between chirality, protease resistance, cellular penetration, and intracellular activity that may be useful for the development of future delivery agents with improved properties.
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Affiliation(s)
- Kristina Najjar
- From the Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843
| | - Alfredo Erazo-Oliveras
- From the Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843
| | - Dakota J Brock
- From the Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843
| | - Ting-Yi Wang
- From the Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843
| | - Jean-Philippe Pellois
- From the Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843
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22
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Thomas JC, Cooper JM, Clayton NS, Wang C, White MA, Abell C, Owen D, Mott HR. Inhibition of Ral GTPases Using a Stapled Peptide Approach. J Biol Chem 2016; 291:18310-25. [PMID: 27334922 DOI: 10.1074/jbc.m116.720243] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Indexed: 01/31/2023] Open
Abstract
Aberrant Ras signaling drives numerous cancers, and drugs to inhibit this are urgently required. This compelling clinical need combined with recent innovations in drug discovery including the advent of biologic therapeutic agents, has propelled Ras back to the forefront of targeting efforts. Activated Ras has proved extremely difficult to target directly, and the focus has moved to the main downstream Ras-signaling pathways. In particular, the Ras-Raf and Ras-PI3K pathways have provided conspicuous enzyme therapeutic targets that were more accessible to conventional drug-discovery strategies. The Ras-RalGEF-Ral pathway is a more difficult challenge for traditional medicinal development, and there have, therefore, been few inhibitors reported that disrupt this axis. We have used our structure of a Ral-effector complex as a basis for the design and characterization of α-helical-stapled peptides that bind selectively to active, GTP-bound Ral proteins and that compete with downstream effector proteins. The peptides have been thoroughly characterized biophysically. Crucially, the lead peptide enters cells and is biologically active, inhibiting isoform-specific RalB-driven cellular processes. This, therefore, provides a starting point for therapeutic inhibition of the Ras-RalGEF-Ral pathway.
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Affiliation(s)
- Jemima C Thomas
- From the Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, United Kingdom, Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Jonathan M Cooper
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, Texas 75390-9039
| | - Natasha S Clayton
- From the Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, United Kingdom
| | - Chensu Wang
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, Texas 75390-9039
| | - Michael A White
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, Texas 75390-9039
| | - Chris Abell
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Darerca Owen
- From the Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, United Kingdom,
| | - Helen R Mott
- From the Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, United Kingdom,
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23
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Deuis JR, Dekan Z, Inserra MC, Lee TH, Aguilar MI, Craik DJ, Lewis RJ, Alewood PF, Mobli M, Schroeder CI, Henriques ST, Vetter I. Development of a μO-Conotoxin Analogue with Improved Lipid Membrane Interactions and Potency for the Analgesic Sodium Channel NaV1.8. J Biol Chem 2016; 291:11829-42. [PMID: 27026701 DOI: 10.1074/jbc.m116.721662] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Indexed: 12/19/2022] Open
Abstract
The μO-conotoxins MrVIA, MrVIB, and MfVIA inhibit the voltage-gated sodium channel NaV1.8, a well described target for the treatment of pain; however, little is known about the residues or structural elements that define this activity. In this study, we determined the three-dimensional structure of MfVIA, examined its membrane binding properties, performed alanine-scanning mutagenesis, and identified residues important for its activity at human NaV1.8. A second round of mutations resulted in (E5K,E8K)MfVIA, a double mutant with greater positive surface charge and greater affinity for lipid membranes compared with MfVIA. This analogue had increased potency at NaV1.8 and was analgesic in the mouse formalin assay.
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Affiliation(s)
- Jennifer R Deuis
- From the Institute for Molecular Bioscience and School of Pharmacy, The University of Queensland, Woolloongabba, Queensland 4102, Australia, and
| | | | - Marco C Inserra
- From the Institute for Molecular Bioscience and School of Pharmacy, The University of Queensland, Woolloongabba, Queensland 4102, Australia, and
| | - Tzong-Hsien Lee
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
| | - Marie-Isabel Aguilar
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
| | | | | | | | - Mehdi Mobli
- Centre for Advanced Imaging, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | | | | | - Irina Vetter
- From the Institute for Molecular Bioscience and School of Pharmacy, The University of Queensland, Woolloongabba, Queensland 4102, Australia, and
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24
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Green BR, Gajewiak J, Chhabra S, Skalicky JJ, Zhang MM, Rivier JE, Bulaj G, Olivera BM, Yoshikami D, Norton RS. Structural Basis for the Inhibition of Voltage-gated Sodium Channels by Conotoxin μO§-GVIIJ. J Biol Chem 2016; 291:7205-20. [PMID: 26817840 DOI: 10.1074/jbc.m115.697672] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Indexed: 11/06/2022] Open
Abstract
Cone snail toxins are well known blockers of voltage-gated sodium channels, a property that is of broad interest in biology and therapeutically in treating neuropathic pain and neurological disorders. Although most conotoxin channel blockers function by direct binding to a channel and disrupting its normal ion movement, conotoxin μO§-GVIIJ channel blocking is unique, using both favorable binding interactions with the channel and a direct tether via an intermolecular disulfide bond. Disulfide exchange is possible because conotoxin μO§-GVIIJ contains anS-cysteinylated Cys-24 residue that is capable of exchanging with a free cysteine thiol on the channel surface. Here, we present the solution structure of an analog of μO§-GVIIJ (GVIIJ[C24S]) and the results of structure-activity studies with synthetic μO§-GVIIJ variants. GVIIJ[C24S] adopts an inhibitor cystine knot structure, with two antiparallel β-strands stabilized by three disulfide bridges. The loop region linking the β-strands (loop 4) presents residue 24 in a configuration where it could bind to the proposed free cysteine of the channel (Cys-910, rat NaV1.2 numbering; at site 8). The structure-activity study shows that three residues (Lys-12, Arg-14, and Tyr-16) located in loop 2 and spatially close to residue 24 were also important for functional activity. We propose that the interaction of μO§-GVIIJ with the channel depends on not only disulfide tethering via Cys-24 to a free cysteine at site 8 on the channel but also the participation of key residues of μO§-GVIIJ on a distinct surface of the peptide.
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Affiliation(s)
- Brad R Green
- From the Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia, the Department of Biology, University of Utah, Salt Lake City, Utah 84112
| | - Joanna Gajewiak
- the Department of Biology, University of Utah, Salt Lake City, Utah 84112
| | - Sandeep Chhabra
- From the Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | | | - Min-Min Zhang
- the Department of Biology, University of Utah, Salt Lake City, Utah 84112
| | - Jean E Rivier
- the Clayton Foundation Laboratories for Peptide Biology, The Salk Institute, La Jolla, California 92037
| | - Grzegorz Bulaj
- the Department of Medicinal Chemistry, College of Pharmacy, University of Utah, Salt Lake City, Utah 84108, and
| | | | - Doju Yoshikami
- the Department of Biology, University of Utah, Salt Lake City, Utah 84112,
| | - Raymond S Norton
- From the Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia,
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25
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Mourier G, Salinas M, Kessler P, Stura EA, Leblanc M, Tepshi L, Besson T, Diochot S, Baron A, Douguet D, Lingueglia E, Servent D. Mambalgin-1 Pain-relieving Peptide, Stepwise Solid-phase Synthesis, Crystal Structure, and Functional Domain for Acid-sensing Ion Channel 1a Inhibition. J Biol Chem 2015; 291:2616-29. [PMID: 26680001 DOI: 10.1074/jbc.m115.702373] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Indexed: 01/04/2023] Open
Abstract
Mambalgins are peptides isolated from mamba venom that specifically inhibit a set of acid-sensing ion channels (ASICs) to relieve pain. We show here the first full stepwise solid phase peptide synthesis of mambalgin-1 and confirm the biological activity of the synthetic toxin both in vitro and in vivo. We also report the determination of its three-dimensional crystal structure showing differences with previously described NMR structures. Finally, the functional domain by which the toxin inhibits ASIC1a channels was identified in its loop II and more precisely in the face containing Phe-27, Leu-32, and Leu-34 residues. Moreover, proximity between Leu-32 in mambalgin-1 and Phe-350 in rASIC1a was proposed from double mutant cycle analysis. These data provide information on the structure and on the pharmacophore for ASIC channel inhibition by mambalgins that could have therapeutic value against pain and probably other neurological disorders.
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Affiliation(s)
- Gilles Mourier
- From the Commissariat à l'Energie Atomique, iBiTecS, Service d'Ingénierie Moléculaire des Protéines, 91191 Gif-sur-Yvette
| | - Miguel Salinas
- the CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, the Université de Nice Sophia Antipolis, and the LabEx Ion Channel Science and Therapeutics, UMR 7275, 06560 Valbonne, France
| | - Pascal Kessler
- From the Commissariat à l'Energie Atomique, iBiTecS, Service d'Ingénierie Moléculaire des Protéines, 91191 Gif-sur-Yvette
| | - Enrico A Stura
- From the Commissariat à l'Energie Atomique, iBiTecS, Service d'Ingénierie Moléculaire des Protéines, 91191 Gif-sur-Yvette
| | - Mathieu Leblanc
- From the Commissariat à l'Energie Atomique, iBiTecS, Service d'Ingénierie Moléculaire des Protéines, 91191 Gif-sur-Yvette
| | - Livia Tepshi
- From the Commissariat à l'Energie Atomique, iBiTecS, Service d'Ingénierie Moléculaire des Protéines, 91191 Gif-sur-Yvette
| | - Thomas Besson
- the CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, the Université de Nice Sophia Antipolis, and the LabEx Ion Channel Science and Therapeutics, UMR 7275, 06560 Valbonne, France
| | - Sylvie Diochot
- the CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, the Université de Nice Sophia Antipolis, and the LabEx Ion Channel Science and Therapeutics, UMR 7275, 06560 Valbonne, France
| | - Anne Baron
- the CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, the Université de Nice Sophia Antipolis, and the LabEx Ion Channel Science and Therapeutics, UMR 7275, 06560 Valbonne, France
| | - Dominique Douguet
- the CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, the Université de Nice Sophia Antipolis, and
| | - Eric Lingueglia
- the CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, the Université de Nice Sophia Antipolis, and the LabEx Ion Channel Science and Therapeutics, UMR 7275, 06560 Valbonne, France
| | - Denis Servent
- From the Commissariat à l'Energie Atomique, iBiTecS, Service d'Ingénierie Moléculaire des Protéines, 91191 Gif-sur-Yvette,
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26
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Fura JM, Kearns D, Pires MM. D-Amino Acid Probes for Penicillin Binding Protein-based Bacterial Surface Labeling. J Biol Chem 2015; 290:30540-50. [PMID: 26499795 DOI: 10.1074/jbc.m115.683342] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Indexed: 02/02/2023] Open
Abstract
Peptidoglycan is an essential and highly conserved mesh structure that surrounds bacterial cells. It plays a critical role in retaining a defined cell shape, and, in the case of pathogenic Gram-positive bacteria, it lies at the interface between bacterial cells and the host organism. Intriguingly, bacteria can metabolically incorporate unnatural D-amino acids into the peptidoglycan stem peptide directly from the surrounding medium, a process mediated by penicillin binding proteins (PBPs). Metabolic peptidoglycan remodeling via unnatural D-amino acids has provided unique insights into peptidoglycan biosynthesis of live bacteria and has also served as the basis of a synthetic immunology strategy with potential therapeutic implications. A striking feature of this process is the vast promiscuity displayed by PBPs in tolerating entirely unnatural side chains. However, the chemical space and physical features of this side chain promiscuity have not been determined systematically. In this report, we designed and synthesized a library of variants displaying diverse side chains to comprehensively establish the tolerability of unnatural D-amino acids by PBPs in both Gram-positive and Gram-negative organisms. In addition, nine Bacillus subtilis PBP-null mutants were evaluated with the goal of identifying a potential primary PBP responsible for unnatural D-amino acid incorporation and gaining insights into the temporal control of PBP activity. We empirically established the scope of physical parameters that govern the metabolic incorporation of unnatural D-amino acids into bacterial peptidoglycan.
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Affiliation(s)
- Jonathan M Fura
- From the Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania and
| | - Daniel Kearns
- the Department of Biology, Indiana University, Bloomington, Indiana
| | - Marcos M Pires
- From the Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania and
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27
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Kunda S, Yuan Y, Balsara RD, Zajicek J, Castellino FJ. Hydroxyproline-induced Helical Disruption in Conantokin Rl-B Affects Subunit-selective Antagonistic Activities toward Ion Channels of N-Methyl-d-aspartate Receptors. J Biol Chem 2015; 290:18156-18172. [PMID: 26048991 DOI: 10.1074/jbc.m115.650341] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Indexed: 01/10/2023] Open
Abstract
Conantokins are ~20-amino acid peptides present in predatory marine snail venoms that function as allosteric antagonists of ion channels of the N-methyl-d-aspartate receptor (NMDAR). These peptides possess a high percentage of post-/co-translationally modified amino acids, particularly γ-carboxyglutamate (Gla). Appropriately spaced Gla residues allow binding of functional divalent cations, which induces end-to-end α-helices in many conantokins. A smaller number of these peptides additionally contain 4-hydroxyproline (Hyp). Hyp should prevent adoption of the metal ion-induced full α-helix, with unknown functional consequences. To address this disparity, as well as the role of Hyp in conantokins, we have solved the high resolution three-dimensional solution structure of a Gla/Hyp-containing 18-residue conantokin, conRl-B, by high field NMR spectroscopy. We show that Hyp(10) disrupts only a small region of the α-helix of the Mn(2+)·peptide complex, which displays cation-induced α-helices on each terminus of the peptide. The function of conRl-B was examined by measuring its inhibition of NMDA/Gly-mediated current through NMDAR ion channels in mouse cortical neurons. The conRl-B displays high inhibitory selectivity for subclasses of NMDARs that contain the functionally important GluN2B subunit. Replacement of Hyp(10) with N(8)Q results in a Mg(2+)-complexed end-to-end α-helix, accompanied by attenuation of NMDAR inhibitory activity. However, replacement of Hyp(10) with Pro(10) allowed the resulting peptide to retain its inhibitory property but diminished its GluN2B specificity. Thus, these modified amino acids, in specific peptide backbones, play critical roles in their subunit-selective inhibition of NMDAR ion channels, a finding that can be employed to design NMDAR antagonists that function at ion channels of distinct NMDAR subclasses.
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Affiliation(s)
- Shailaja Kunda
- W. M. Keck Center for Transgene Research and Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Yue Yuan
- W. M. Keck Center for Transgene Research and Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Rashna D Balsara
- W. M. Keck Center for Transgene Research and Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Jaroslav Zajicek
- W. M. Keck Center for Transgene Research and Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Francis J Castellino
- W. M. Keck Center for Transgene Research and Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556.
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28
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Hosseini S, Naderi-Manesh H, Mountassif D, Cerruti M, Vali H, Faghihi S. C-terminal amidation of an osteocalcin-derived peptide promotes hydroxyapatite crystallization. J Biol Chem 2013; 288:7885-7893. [PMID: 23362258 PMCID: PMC3597826 DOI: 10.1074/jbc.m112.422048] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2012] [Revised: 01/09/2013] [Indexed: 01/05/2023] Open
Abstract
Genesis of natural biocomposite-based materials, such as bone, cartilage, and teeth, involves interactions between organic and inorganic systems. Natural biopolymers, such as peptide motif sequences, can be used as a template to direct the nucleation and crystallization of hydroxyapatite (HA). In this study, a natural motif sequence consisting of 13 amino acids present in the first helix of osteocalcin was selected based on its calcium binding ability and used as substrate for nucleation of HA crystals. The acidic (acidic osteocalcin-derived peptide (OSC)) and amidic (amidic osteocalcin-derived peptide (OSN)) forms of this sequence were synthesized to investigate the effects of different C termini on the process of biomineralization. Electron microscopy analyses show the formation of plate-like HA crystals with random size and shape in the presence of OSN. In contrast, spherical amorphous calcium phosphate is formed in the presence of OSC. Circular dichroism experiments indicate conformational changes of amidic peptide to an open and regular structure as a consequence of interaction with calcium and phosphate. There is no conformational change detectable in OSC. It is concluded that HA crystal formation, which only occurred in OSN, is attributable to C-terminal amidation of a natural peptide derived from osteocalcin. It is also proposed that natural peptides with the ability to promote biomineralization have the potential to be utilized in hard tissue regeneration.
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Affiliation(s)
- Samaneh Hosseini
- Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran 14115-175, Iran; Tissue Engineering and Biomaterials Division, National Institute of Genetic Engineering and Biotechnology, Tehran 14965/161, Iran
| | - Hossein Naderi-Manesh
- Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran 14115-175, Iran.
| | - Driss Mountassif
- Department of Anatomy and Cell Biology, McGill University, Montréal, Quebec H3A 0C7, Canada
| | - Marta Cerruti
- Department of Mining and Materials Engineering, McGill University, Montréal, Quebec H3A 0C7, Canada
| | - Hojatollah Vali
- Department of Anatomy and Cell Biology, McGill University, Montréal, Quebec H3A 0C7, Canada; Facility for Electron Microscopy Research, McGill University, Montréal, Quebec H3A 0C7, Canada
| | - Shahab Faghihi
- Tissue Engineering and Biomaterials Division, National Institute of Genetic Engineering and Biotechnology, Tehran 14965/161, Iran.
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29
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Grace CRR, Perrin MH, Gulyas J, Rivier JE, Vale WW, Riek R. NMR structure of the first extracellular domain of corticotropin-releasing factor receptor 1 (ECD1-CRF-R1) complexed with a high affinity agonist. J Biol Chem 2010; 285:38580-9. [PMID: 20843795 PMCID: PMC2992290 DOI: 10.1074/jbc.m110.121897] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Revised: 08/06/2010] [Indexed: 01/06/2023] Open
Abstract
The corticotropin-releasing factor (CRF) peptide hormone family members coordinate endocrine, behavioral, autonomic, and metabolic responses to stress and play important roles within the cardiovascular, gastrointestinal, and central nervous systems, among others. The actions of the peptides are mediated by activation of two G-protein-coupled receptors of the B1 family, CRF receptors 1 and 2 (CRF-R1 and CRF-R2α,β). The recently reported three-dimensional structures of the first extracellular domain (ECD1) of both CRF-R1 and CRF-R2β (Pioszak, A. A., Parker, N. R., Suino-Powell, K., and Xu, H. E. (2008) J. Biol. Chem. 283, 32900-32912; Grace, C. R., Perrin, M. H., Gulyas, J., Digruccio, M. R., Cantle, J. P., Rivier, J. E., Vale, W. W., and Riek, R. (2007) Proc. Natl. Acad. Sci. U.S.A. 104, 4858-4863) complexed with peptide antagonists provided a starting point in understanding the binding between CRF ligands and receptors at a molecular level. We now report the three-dimensional NMR structure of the ECD1 of human CRF-R1 complexed with a high affinity agonist, α-helical cyclic CRF. In the structure of the complex, the C-terminal residues (23-41) of α-helical cyclic CRF bind to the ECD1 of CRF-R1 in a helical conformation mainly along the hydrophobic face of the peptide in a manner similar to that of the antagonists in their corresponding ECD1 complex structures. Unique to this study is the observation that complex formation between an agonist and the ECD1-CRF-R1 promotes the helical conformation of the N terminus of the former, important for receptor activation (Gulyas, J., Rivier, C., Perrin, M., Koerber, S. C., Sutton, S., Corrigan, A., Lahrichi, S. L., Craig, A. G., Vale, W., and Rivier, J. (1995) Proc. Natl. Acad. Sci. U.S.A. 92, 10575-10579).
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Affiliation(s)
| | - Marilyn H. Perrin
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, California 92037
| | - Jozsef Gulyas
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, California 92037
| | - Jean E. Rivier
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, California 92037
| | - Wylie W. Vale
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, California 92037
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30
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Da Silva P, Rahioui I, Laugier C, Jouvensal L, Meudal H, Chouabe C, Delmas AF, Gressent F. Molecular requirements for the insecticidal activity of the plant peptide pea albumin 1 subunit b (PA1b). J Biol Chem 2010; 285:32689-32694. [PMID: 20660598 PMCID: PMC2963353 DOI: 10.1074/jbc.m110.147199] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Revised: 07/07/2010] [Indexed: 11/06/2022] Open
Abstract
PA1b (pea albumin 1, subunit b) is a small and compact 37-amino acid protein, isolated from pea seeds (Pisum sativum), that adopts a cystine knot fold. It acts as a potent insecticidal agent against major pests in stored crops and vegetables, making it a promising bioinsecticide. Here, we investigate the influence of individual residues on the structure and bioactivity of PA1b. A collection of 13 PA1b mutants was successfully chemically synthesized in which the residues involved in the definition of PA1b amphiphilic and electrostatic characteristics were individually replaced with an alanine. The three-dimensional structure of PA1b was outstandingly tolerant of modifications. Remarkably, receptor binding and insecticidal activities were both dependent on common well defined clusters of residues located on one single face of the toxin, with Phe-10, Arg-21, Ile-23, and Leu-27 being key residues of the binding interaction. The inactivity of the mutants is clearly due to a change in the nature of the side chain rather than to a side effect, such as misfolding or degradation of the peptide, in the insect digestive tract. We have shown that a hydrophobic patch is the putative site of the interaction of PA1b with its binding site. Overall, the mutagenesis data provide major insights into the functional elements responsible for PA1b entomotoxic properties and give some clues toward a better understanding of the PA1b mode of action.
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Affiliation(s)
- Pedro Da Silva
- From the Institut National de la Recherche Agronomique (INRA), Institut National des Sciences Appliquées de Lyon (INSA-Lyon), IFR-41, UMR203 BF2I, Biologie Fonctionnelle, Insectes et Interactions, Université de Lyon, Bâtiment Louis Pasteur, F-69621 Villeurbanne.
| | - Isabelle Rahioui
- From the Institut National de la Recherche Agronomique (INRA), Institut National des Sciences Appliquées de Lyon (INSA-Lyon), IFR-41, UMR203 BF2I, Biologie Fonctionnelle, Insectes et Interactions, Université de Lyon, Bâtiment Louis Pasteur, F-69621 Villeurbanne
| | - Christian Laugier
- From the Institut National de la Recherche Agronomique (INRA), Institut National des Sciences Appliquées de Lyon (INSA-Lyon), IFR-41, UMR203 BF2I, Biologie Fonctionnelle, Insectes et Interactions, Université de Lyon, Bâtiment Louis Pasteur, F-69621 Villeurbanne
| | - Laurence Jouvensal
- Centre de Biophysique Moléculaire, UPR 4301 CNRS, University of Orléans and INSERM, rue Charles Sadron, 45071 Orléans Cedex 2
| | - Hervé Meudal
- Centre de Biophysique Moléculaire, UPR 4301 CNRS, University of Orléans and INSERM, rue Charles Sadron, 45071 Orléans Cedex 2
| | - Christophe Chouabe
- CNRS UMR 5123, Physiologie des Régulations Energétiques, Cellulaires et Moléculaires, Campus de la Doua, Université de Lyon 1, 69622 Villeurbanne, France
| | - Agnès F Delmas
- Centre de Biophysique Moléculaire, UPR 4301 CNRS, University of Orléans and INSERM, rue Charles Sadron, 45071 Orléans Cedex 2
| | - Frédéric Gressent
- From the Institut National de la Recherche Agronomique (INRA), Institut National des Sciences Appliquées de Lyon (INSA-Lyon), IFR-41, UMR203 BF2I, Biologie Fonctionnelle, Insectes et Interactions, Université de Lyon, Bâtiment Louis Pasteur, F-69621 Villeurbanne
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Chen X, Ren L, Kim S, Carpino N, Daniel JL, Kunapuli SP, Tsygankov AY, Pei D. Determination of the substrate specificity of protein-tyrosine phosphatase TULA-2 and identification of Syk as a TULA-2 substrate. J Biol Chem 2010; 285:31268-76. [PMID: 20670933 PMCID: PMC2951201 DOI: 10.1074/jbc.m110.114181] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2010] [Revised: 07/28/2010] [Indexed: 11/06/2022] Open
Abstract
TULA-1 (UBASH3A/STS-2) and TULA-2 (p70/STS-1) represent a novel class of protein-tyrosine phosphatases. Previous studies suggest that TULA-2 is sequence-selective toward phosphotyrosyl (Tyr(P)) peptides. In this work the substrate specificity of TULA-1 and -2 was systematically evaluated by screening a combinatorial Tyr(P) peptide library. Although TULA-1 showed no detectable activity toward any of the Tyr(P) peptides in the library, TULA-2 recognizes two distinct classes of Tyr(P) substrates. On the N-terminal side of Tyr(P), the class I substrates contain a proline at the Tyr(P)-1 position, a hydrophilic residue at the Tyr(P)-2 position, and aromatic hydrophobic residues at positions Tyr(P)-3 and beyond. The class II substrates typically contain two or more acidic residues, especially at Tyr(P)-1 to Tyr(P)-3 positions, and aromatic hydrophobic residues at other positions. At the C-terminal side of Tyr(P), TULA-2 generally prefers acidic and aromatic residues. The library screening results were confirmed by kinetic analysis of representative peptides selected from the library as well as Tyr(P) peptides derived from various Tyr(P) proteins. TULA-2 is highly active toward peptides corresponding to the Tyr(P)-323 and Tyr(P)-352 sites of Syk, and the Tyr(P)-397 site of focal adhesion kinase and has lower activity toward other Tyr(P) sites in these proteins. In glycoprotein VI-stimulated platelets, knock-out of the TULA-2 gene significantly increased the phosphorylation level of Syk at Tyr-323 and Tyr-352 sites and to a lesser degree at the Tyr-525/526 sites. These results suggest that Syk is a bona fide TULA-2 substrate in platelets.
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Affiliation(s)
- Xianwen Chen
- From the Department of Chemistry and Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio 43210
| | - Lige Ren
- From the Department of Chemistry and Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio 43210
| | | | - Nicholas Carpino
- the Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York 11794, and
| | - James L. Daniel
- Pharmacology
- the Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania 19140
| | - Satya P. Kunapuli
- Physiology, and
- the Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania 19140
| | - Alexander Y. Tsygankov
- the Departments of Microbiology and Immunology
- the Fels Institute for Cancer Research and Molecular Biology, and
- the Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania 19140
| | - Dehua Pei
- From the Department of Chemistry and Ohio State Biochemistry Program, The Ohio State University, Columbus, Ohio 43210
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Vostrikov VV, Daily AE, Greathouse DV, Koeppe RE. Charged or aromatic anchor residue dependence of transmembrane peptide tilt. J Biol Chem 2010; 285:31723-30. [PMID: 20667827 PMCID: PMC2951244 DOI: 10.1074/jbc.m110.152470] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Revised: 07/15/2010] [Indexed: 01/13/2023] Open
Abstract
The membrane-spanning segments of integral membrane proteins often are flanked by aromatic or charged amino acid residues, which may "anchor" the transmembrane orientation. Single spanning transmembrane peptides such as those of the WALP family, acetyl-GWW(LA)(n)LWWA-amide, furthermore adopt a moderate average tilt within lipid bilayer membranes. To understand the anchor residue dependence of the tilt, we introduce Leu-Ala "spacers" between paired anchors and in some cases replace the outer tryptophans. The resulting peptides, acetyl-GX(2)ALW(LA)(6)LWLAX(22)A-amide, have Trp, Lys, Arg, or Gly in the two X positions. The apparent average orientations of the core helical sequences were determined in oriented phosphatidylcholine bilayer membranes of varying thickness using solid-state (2)H NMR spectroscopy. When X is Lys, Arg, or Gly, the direction of the tilt is essentially constant in different lipids and presumably is dictated by the tryptophans (Trp(5) and Trp(19)) that flank the inner helical core. The Leu-Ala spacers are no longer helical. The magnitude of the apparent helix tilt furthermore scales nicely with the bilayer thickness except when X is Trp. When X is Trp, the direction of tilt is less well defined in each phosphatidylcholine bilayer and varies up to 70° among 1,2-dioleoyl-sn-glycero-3-phosphocholine, 1,2-dimyristoyl-sn-glycero-3-phosphocholine, and 1,2-dilauroyl-sn-glycero-3-phosphocholine bilayer membranes. Indeed, the X = Trp case parallels earlier observations in which WALP family peptides having multiple Trp anchors show little dependence of the apparent tilt magnitude on bilayer thickness. The results shed new light on the interactions of arginine, lysine, tryptophan, and even glycine at lipid bilayer membrane interfaces.
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Affiliation(s)
- Vitaly V. Vostrikov
- From the Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701
| | - Anna E. Daily
- From the Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701
| | - Denise V. Greathouse
- From the Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701
| | - Roger E. Koeppe
- From the Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701
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