1
|
Du S, Wey M, Armstrong DW. d-Amino acids in biological systems. Chirality 2023; 35:508-534. [PMID: 37074214 DOI: 10.1002/chir.23562] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 03/06/2023] [Accepted: 03/07/2023] [Indexed: 04/20/2023]
Abstract
Investigations on the occurrence and biochemical roles of free D-amino acids and D-amino acid-containing peptides and proteins in living systems have increased in frequency and significance. Their occurrence and roles may vary substantially with progression from microbiotic to evermore advanced macrobiotic systems. We now understand many of the biosynthetic and regulatory pathways, which are outlined herein. Important uses for D-amino acids in plants, invertebrates, and vertebrates are reviewed. Given its importance, a separate section on the occurrence and role of D-amino acids in human disease is presented.
Collapse
Affiliation(s)
- Siqi Du
- Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington, Texas, USA
| | - Michael Wey
- Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington, Texas, USA
| | - Daniel W Armstrong
- Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington, Texas, USA
| |
Collapse
|
2
|
Wubulikasimu A, He Z, Long Y, Yuan F, Hou W, Liao Q, Chen H, Rong M. Molecular mechanism of HNTX-I activates the intermediate-conductance Ca 2+-activated K + (IK) channels. Int J Biol Macromol 2023:125197. [PMID: 37285887 DOI: 10.1016/j.ijbiomac.2023.125197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 05/30/2023] [Accepted: 05/31/2023] [Indexed: 06/09/2023]
Abstract
The IK channel, a potassium ion channel regulated by calcium ions and voltages in a bidirectional manner, has been implicated in a range of diseases. However, there are currently few compounds available that can target the IK channel with high potency and specificity. Hainantoxin-I (HNTX-I) is the first peptide activator of IK channel discovered so far, but its activity is not ideal, and the underlying mechanism interaction between HNTX-I toxin and IK channel remains unclear. Thus, our study aimed to enhance the potency of IK channel activating peptides derived from HNTX-I and elucidate the molecular mechanism underlying the interaction between HNTX-I and the IK channel. By employing virtual alanine scanning mutagenesis, we generated 11 HNTX-I mutants using site-directed mutagenesis to pinpoint specific residues crucial for the HNTX-I and IK channel interaction. Subsequently, we identified key residues on the IK channel that are involved in the interaction with HNTX-I. Additionally, molecular docking was employed to guide the molecular engineering process and clarify the binding interface between HNTX-I and the IK channel. Our results demonstrate that HNTX-I primarily acts on the IK channel via the N-terminal amino acid, and its interaction with the IK channel is mediated by electrostatic and hydrophobic interactions, specifically the amino acid residues at positions 1, 3, 5, and 7 on HNTX-I. This study provides valuable insights into the peptide toxins that may serve as potential templates for the development of activators with enhanced potency and selectivity for the IK channel.
Collapse
Affiliation(s)
- Atikan Wubulikasimu
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha 410081, People's Republic of China
| | - Ziyan He
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha 410081, People's Republic of China
| | - Yanping Long
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha 410081, People's Republic of China
| | - Fuchu Yuan
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha 410081, People's Republic of China
| | - Wenqian Hou
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha 410081, People's Republic of China
| | - Qiong Liao
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha 410081, People's Republic of China
| | - Haiyan Chen
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha 410081, People's Republic of China.
| | - Mingqiang Rong
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha 410081, People's Republic of China.
| |
Collapse
|
3
|
Groome JR. Historical Perspective of the Characterization of Conotoxins Targeting Voltage-Gated Sodium Channels. Mar Drugs 2023; 21:md21040209. [PMID: 37103349 PMCID: PMC10142487 DOI: 10.3390/md21040209] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/21/2023] [Accepted: 03/24/2023] [Indexed: 03/30/2023] Open
Abstract
Marine toxins have potent actions on diverse sodium ion channels regulated by transmembrane voltage (voltage-gated ion channels) or by neurotransmitters (nicotinic acetylcholine receptor channels). Studies of these toxins have focused on varied aspects of venom peptides ranging from evolutionary relationships of predator and prey, biological actions on excitable tissues, potential application as pharmacological intervention in disease therapy, and as part of multiple experimental approaches towards an understanding of the atomistic characterization of ion channel structure. This review examines the historical perspective of the study of conotoxin peptides active on sodium channels gated by transmembrane voltage, which has led to recent advances in ion channel research made possible with the exploitation of the diversity of these marine toxins.
Collapse
Affiliation(s)
- James R Groome
- Department of Biological Sciences, Idaho State University, Pocatello, ID 83209, USA
| |
Collapse
|
4
|
Mordhorst S, Ruijne F, Vagstad AL, Kuipers OP, Piel J. Emulating nonribosomal peptides with ribosomal biosynthetic strategies. RSC Chem Biol 2023; 4:7-36. [PMID: 36685251 PMCID: PMC9811515 DOI: 10.1039/d2cb00169a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 11/28/2022] [Indexed: 12/12/2022] Open
Abstract
Peptide natural products are important lead structures for human drugs and many nonribosomal peptides possess antibiotic activity. This makes them interesting targets for engineering approaches to generate peptide analogues with, for example, increased bioactivities. Nonribosomal peptides are produced by huge mega-enzyme complexes in an assembly-line like manner, and hence, these biosynthetic pathways are challenging to engineer. In the past decade, more and more structural features thought to be unique to nonribosomal peptides were found in ribosomally synthesised and posttranslationally modified peptides as well. These streamlined ribosomal pathways with modifying enzymes that are often promiscuous and with gene-encoded precursor proteins that can be modified easily, offer several advantages to produce designer peptides. This review aims to provide an overview of recent progress in this emerging research area by comparing structural features common to both nonribosomal and ribosomally synthesised and posttranslationally modified peptides in the first part and highlighting synthetic biology strategies for emulating nonribosomal peptides by ribosomal pathway engineering in the second part.
Collapse
Affiliation(s)
- Silja Mordhorst
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4 8093 Zürich Switzerland
| | - Fleur Ruijne
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen Nijenborgh 7, 9747 AG Groningen The Netherlands
| | - Anna L Vagstad
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4 8093 Zürich Switzerland
| | - Oscar P Kuipers
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen Nijenborgh 7, 9747 AG Groningen The Netherlands
| | - Jörn Piel
- Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, Vladimir-Prelog-Weg 4 8093 Zürich Switzerland
| |
Collapse
|
5
|
Moi S, Shekh S, Dolle A, Vijayasarathy M, Gowd KH. Significance of D- tryptophan in Contryphan-Ar1131 Conus peptide: Oxidative folding, trypsin binding, and photostabilization activity. Peptides 2022; 156:170845. [PMID: 35902005 DOI: 10.1016/j.peptides.2022.170845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 07/06/2022] [Accepted: 07/23/2022] [Indexed: 11/28/2022]
Abstract
Distinct differences have been observed between L-tryptophan and D-tryptophan containing contryphan-Ar1131 in oxidative folding, trypsin binding, and photostabilization activity on avobenzone. [W5] contryphan-Ar1131 and [w5] contryphan-Ar1131 were chemically synthesized and characterized using RP-HPLC and mass spectrometry. Structural differences due to the change of configuration of tryptophan were evident from the optimized structures of contryphan-Ar1131 using density functional theory (DFT). The comparison of early events of oxidative folding has revealed the role of D-tryptophan in accelerating the formation of a disulfide bond. The optimized structures of the reduced form of peptides revealed the occurrence of aromatic-aromatic and aromatic-proline interactions in [w5] contryphan-Ar1131 which may be critical in aiding the oxidative folding reaction. The presence of the Lys6-Pro7 peptide bond indicates that contryphan-Ar1131 is resistant but may bind to trypsin allowing to assign the binding affinity of peptides to the protein surface. Competitive binding studies and molecular docking along with molecular dynamic (MD) simulations have revealed that [w5] contryphan-Ar1131 has more affinity for the active site of trypsin. Given tryptophan is a photostabilizer of FDA-approved chemical UV-A filter avobenzone, the report has compared the photostabilization activity of [W5]/ [w5] contryphan-Ar1131 on avobenzone under natural sunlight. [w5] contryphan-Ar1131 has better photostabilization activity than that of [W5] contryphan-Ar1131 and also individual D-tryptophan and L-tryptophan amino acids. These biochemical studies have highlighted the significance of D-tryptophan in contryphan-Ar1131 and its photostabilization activity on avobenzone may find applications in cosmetics.
Collapse
Affiliation(s)
- Smriti Moi
- Department of Chemistry, School of Chemical Sciences, Central University of Karnataka, Kalaburagi 585367, Karnataka, India
| | - Shamasoddin Shekh
- Department of Chemistry, School of Chemical Sciences, Central University of Karnataka, Kalaburagi 585367, Karnataka, India
| | - Ashwini Dolle
- Department of Chemistry, School of Chemical Sciences, Central University of Karnataka, Kalaburagi 585367, Karnataka, India
| | | | - Konkallu Hanumae Gowd
- Department of Chemistry, School of Chemical Sciences, Central University of Karnataka, Kalaburagi 585367, Karnataka, India.
| |
Collapse
|
6
|
Yussif BM, Checco JW. Evaluation of endogenous peptide stereochemistry using liquid chromatography-mass spectrometry-based spiking experiments. Methods Enzymol 2022; 663:205-234. [DOI: 10.1016/bs.mie.2021.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
7
|
Berthias F, Baird MA, Shvartsburg AA. Differential Ion Mobility Separations of d/l Peptide Epimers. Anal Chem 2021; 93:4015-4022. [DOI: 10.1021/acs.analchem.0c05023] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Francis Berthias
- Department of Chemistry, Wichita State University, 1845 Fairmount, Wichita, Kansas 67260, United States
| | - Matthew A. Baird
- Department of Chemistry, Wichita State University, 1845 Fairmount, Wichita, Kansas 67260, United States
| | - Alexandre A. Shvartsburg
- Department of Chemistry, Wichita State University, 1845 Fairmount, Wichita, Kansas 67260, United States
| |
Collapse
|
8
|
Mast DH, Checco JW, Sweedler JV. Advancing d-amino acid-containing peptide discovery in the metazoan. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1869:140553. [PMID: 33002629 DOI: 10.1016/j.bbapap.2020.140553] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 09/01/2020] [Accepted: 09/25/2020] [Indexed: 12/12/2022]
Abstract
The discovery of enzyme-derived d-amino acid-containing peptides (DAACPs) that have physiological importance in the metazoan challenges previous assumptions about the homochirality of animal proteins while simultaneously revealing new analytical challenges in the structural and functional characterization of peptides. Most known DAACPs have been identified though laborious activity-guided purification studies or by homology to previously identified DAACPs. Peptide characterization experiments are increasingly dominated by high throughput mass spectrometry-based peptidomics, with stereochemistry rarely considered due to the technical challenges of identifying l/d isomerization. This review discusses the prevalence of enzyme-derived DAACPs among animals and the physiological consequences of peptide isomerization. Also highlighted are the analytical methods that have been applied for structural characterization/discovery of DAACPs, including results of several recent studies using non-targeted discovery methods for revealing novel DAACPs, strongly suggesting that more DAACPs remain to be uncovered.
Collapse
Affiliation(s)
- David H Mast
- Department of Chemistry and the Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| | - James W Checco
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE 68588, United States.
| | - Jonathan V Sweedler
- Department of Chemistry and the Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States.
| |
Collapse
|
9
|
Discovery of a Novel Cysteine Framework XXIV Conotoxin from Conus striatus, S24a, with Potential Analgesic Activity. Int J Pept Res Ther 2020. [DOI: 10.1007/s10989-020-10109-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
10
|
Jimenez EC. D-Amino Acids in Peptides from Animals, Including Human: Occurrence, Structure, Bioactivity and Pharmacology. Curr Protein Pept Sci 2020; 21:622-637. [PMID: 32338216 DOI: 10.2174/1389203721666200426233758] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 02/06/2020] [Accepted: 02/13/2020] [Indexed: 11/22/2022]
Abstract
All life forms typically possess homochirality, with rare exceptions. In the case of peptides and proteins, only L-amino acids are known to be encoded by genes. Nevertheless, D-amino acids have been identified in a variety of peptides, synthesized by animal cells. They include neuroexcitatory and neuroprotective peptides, cardioexcitatory peptides, hyperglycemic hormones, opioid peptides, antimicrobial peptides, natriuretic and defensin-like peptides, and fibrinopeptides. This article is a review of their occurrence, structure and bioactivity. It further explores the pharmacology and potential medical applications of some of the peptides.
Collapse
Affiliation(s)
- Elsie C Jimenez
- Department of Physical Sciences, College of Science, University of the Philippines Baguio, Baguio City 2600, Philippines
| |
Collapse
|
11
|
Himaya SWA, Rai SK, Pamfili G, Jin AH, Alewood PF, Lewis RJ. Venomic Interrogation Reveals the Complexity of Conus striolatus Venom. Aust J Chem 2020. [DOI: 10.1071/ch19588] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Given the complexity of cone snail venoms, high throughput venomics approaches are required to fully investigate venom composition, envenomation strategies, and evolutionary trajectories. This study describes 158 conotoxins in the venom transcriptome of the little studied C. striolatus from the fish hunting clade Pionoconus. Despite similar gene superfamily distributions along the venom duct, only 18 common transcripts were identified between distal, central, and proximal venom duct transcriptomes. Proteomic analysis of the injected predatory venom collected from the same individual revealed an ~18-fold enhanced complexity at the proteomic level, consistent with complex post-translational modifications and variable venom peptide processing occurring in the venom duct. Overall, C. striolatus venom was dominated by M, O1, O2, and A gene superfamily conotoxins and conkunitzins, which are potential modulators of sodium, calcium, and potassium channels. Conkunitzins and gene superfamily A peptides dominated the proximal over the distal duct, the M and O1 gene superfamily peptides were distributed along the full length of the duct, while the O2 gene superfamily peptides dominated the distal duct. Interestingly, the predatory injected venom of C. striolatus was dominated by peptides from gene superfamilies M, O1, O2, A, and conkunitzins, suggesting the predatory venom of C. striolatus may arise at multiple sites along the venom duct.
Collapse
|
12
|
Antimycobacterial Activity: A New Pharmacological Target for Conotoxins Found in the First Reported Conotoxin from Conasprella ximenes. Toxins (Basel) 2018; 10:toxins10020051. [PMID: 29360782 PMCID: PMC5848152 DOI: 10.3390/toxins10020051] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 01/11/2018] [Accepted: 01/17/2018] [Indexed: 12/24/2022] Open
Abstract
Mycobacterium tuberculosis is the etiological agent of tuberculosis, an airborne infectious disease that is a leading cause of human morbidity and mortality worldwide. We report here the first conotoxin that is able to inhibit the growth of M. tuberculosis at a concentration similar to that of two other drugs that are currently used in clinics. Furthermore, it is also the first conopeptide that has been isolated from the venom of Conasprella ximenes. The venom gland transcriptome of C. ximenes was sequenced to construct a database with 24,284 non-redundant transcripts. The conopeptide was purified from the venom using reverse phase high performance liquid chromatography (RP-HPLC) and was analyzed using electrospray ionization-mass spectrometry (ESI-MS/MS). No automatic identification above the identity threshold with 1% of the false discovery rate was obtained; however, a 10-amino-acid sequence tag, manually extracted from the MS/MS spectra, allowed for the identification of a conotoxin in the transcriptome database. Electron transfer higher energy collision dissociation (EThcD) fragmentation of the native conotoxin confirmed the N-terminal sequence (1–14), while LC-MS/MS analysis of the tryptic digest of the reduced and S-alkylated conotoxin confirmed the C-terminal region (15–36). The expected and experimental molecular masses corresponded, within sub-ppm mass error. The 37-mer peptide (MW 4109.69 Da), containing eight cysteine residues, was named I1_xm11a, according to the current nomenclature for this type of molecule.
Collapse
|
13
|
Robinson SD, Undheim EAB, Ueberheide B, King GF. Venom peptides as therapeutics: advances, challenges and the future of venom-peptide discovery. Expert Rev Proteomics 2017; 14:931-939. [DOI: 10.1080/14789450.2017.1377613] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Samuel D. Robinson
- Institute for Molecular Bioscience, University of Queensland, St Lucia, Australia
- Centre for Advanced Imaging, University of Queensland, St Lucia, Australia
| | | | | | - Glenn F. King
- Institute for Molecular Bioscience, University of Queensland, St Lucia, Australia
| |
Collapse
|
14
|
Koehbach J, Gruber CW, Becker C, Kreil DP, Jilek A. MALDI TOF/TOF-Based Approach for the Identification of d- Amino Acids in Biologically Active Peptides and Proteins. J Proteome Res 2016; 15:1487-96. [PMID: 26985971 PMCID: PMC4861975 DOI: 10.1021/acs.jproteome.5b01067] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
![]()
Several
biologically active peptides contain a d- amino
acid in a well-defined position, which is position 2 in all peptide
epimers isolated to date from vertebrates and also some from invertebrates.
The detection of such D- residues by standard analytical
techniques is challenging. In tandem mass spectrometric (MS) analysis,
although fragment masses are the same for all stereoisomers, peak
intensities are known to depend on chirality. Here, we observe that
the effect of a d- amino acid in the second N-terminal position
on the fragmentation pattern in matrix assisted laser desorption time-of-flight
spectrometry (MALDI-TOF/TOF MS) strongly depends on the peptide sequence.
Stereosensitive fragmentation (SF) is correlated to a neighborhood
effect, but the d- residue also exerts an overall effect
influencing distant bonds. In a fingerprint analysis, multiple peaks
can thus serve to identify the chirality of a sample in short time
and potentially high throughput. Problematic variations between individual
spots could be successfully suppressed by cospotting deuterated analogues
of the epimers. By identifying the [d-Leu2] isomer of the
predicted peptide GH-2 (gene derived bombininH) in skin secretions
of the toad Bombina orientalis, we
demonstrated the analytical power of SF-MALDI-TOF/TOF measurements.
In conclusion, SF-MALDI-TOF/TOF MS combines high sensitivity, versatility,
and the ability to complement other methods.
Collapse
Affiliation(s)
- Johannes Koehbach
- Centre for Physiology and Pharmacology, Medical University of Vienna , Schwarzspanierstraße 17, A-1090 Vienna, Austria.,School of Biomedical Sciences, The University of Queensland , Brisbane, QLD, 4072 Australia
| | - Christian W Gruber
- Centre for Physiology and Pharmacology, Medical University of Vienna , Schwarzspanierstraße 17, A-1090 Vienna, Austria
| | - Christian Becker
- Institute of Biological Chemistry, Department of Chemistry, University of Vienna , Währinger Straße 38, A-1090 Vienna, Austria
| | - David P Kreil
- Chair of Bioinformatics, University of Natural Resources and Life Sciences , Muthgasse 18, A-1190 Vienna, Austria
| | - Alexander Jilek
- Institute of Biological Chemistry, Department of Chemistry, University of Vienna , Währinger Straße 38, A-1090 Vienna, Austria.,Chair of Bioinformatics, University of Natural Resources and Life Sciences , Muthgasse 18, A-1190 Vienna, Austria
| |
Collapse
|
15
|
Optimized deep-targeted proteotranscriptomic profiling reveals unexplored Conus toxin diversity and novel cysteine frameworks. Proc Natl Acad Sci U S A 2015; 112:E3782-91. [PMID: 26150494 DOI: 10.1073/pnas.1501334112] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cone snails are predatory marine gastropods characterized by a sophisticated venom apparatus responsible for the biosynthesis and delivery of complex mixtures of cysteine-rich toxin peptides. These conotoxins fold into small highly structured frameworks, allowing them to potently and selectively interact with heterologous ion channels and receptors. Approximately 2,000 toxins from an estimated number of >70,000 bioactive peptides have been identified in the genus Conus to date. Here, we describe a high-resolution interrogation of the transcriptomes (available at www.ddbj.nig.ac.jp) and proteomes of the diverse compartments of the Conus episcopatus venom apparatus. Using biochemical and bioinformatic tools, we found the highest number of conopeptides yet discovered in a single Conus specimen, with 3,305 novel precursor toxin sequences classified into 9 known superfamilies (A, I1, I2, M, O1, O2, S, T, Z), and identified 16 new superfamilies showing unique signal peptide signatures. We were also able to depict the largest population of venom peptides containing the pharmacologically active C-C-CC-C-C inhibitor cystine knot and CC-C-C motifs (168 and 44 toxins, respectively), as well as 208 new conotoxins displaying odd numbers of cysteine residues derived from known conotoxin motifs. Importantly, six novel cysteine-rich frameworks were revealed which may have novel pharmacology. Finally, analyses of codon usage bias and RNA-editing processes of the conotoxin transcripts demonstrate a specific conservation of the cysteine skeleton at the nucleic acid level and provide new insights about the origin of sequence hypervariablity in mature toxin regions.
Collapse
|
16
|
Rajesh RP. Novel M-Superfamily and T-Superfamily conotoxins and contryphans from the vermivorous snail Conus figulinus. J Pept Sci 2014; 21:29-39. [PMID: 25420928 DOI: 10.1002/psc.2715] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 10/22/2014] [Accepted: 10/22/2014] [Indexed: 12/23/2022]
Abstract
The venom of Conus figulinus, a vermivorous cone snail, found in the south east coast of India, has been studied in an effort to identify novel peptide toxins. The amino acid sequences of seven peptides have been established using de novo mass spectrometric based sequencing methods. Among these, three peptides belong to the M-Superfamily conotoxins, namely, Fi3a, Fi3b, and Fi3c, and one that belongs to the T-Superfamily, namely, Fi5a. The other three peptides are contryphans, namely, contryphans fib, fic, and fid. Of these Fi3b, Fi3c, Fi5a, and contryphan fib are novel and are reported for the first time from venom of C. figulinus. The details of the sequencing methods and the relationship of these peptides with other 'M'-Superfamily conotoxins from the fish hunting and mollusk hunting clades are discussed. These novel peptides could serve as a lead compounds for the development of neuropharmacologically important drugs.
Collapse
|
17
|
Thapa P, Espiritu MJ, Cabalteja CC, Bingham JP. Conotoxins and their regulatory considerations. Regul Toxicol Pharmacol 2014; 70:197-202. [PMID: 25013992 DOI: 10.1016/j.yrtph.2014.06.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 06/29/2014] [Accepted: 06/30/2014] [Indexed: 01/21/2023]
Abstract
Venom derived peptides from marine cone snails, conotoxins, have demonstrated unique pharmacological targeting properties that have been pivotal in advancing medical research. The awareness of their true toxic origins and potent pharmacological nature is emphasized by their 'select agent' classification by the US Centers for Disease Control and Prevention. We briefly introduce the biochemical and pharmacological aspects of conotoxins, highlighting current advancements into their biological engineering, and provide details to the present regulations that govern their use in research.
Collapse
Affiliation(s)
- Parashar Thapa
- Department of Molecular Biosciences and Bioengineering, College of Tropical Agriculture and Human Resources, University of Hawai'i, Honolulu, HI 96822, USA
| | - Michael J Espiritu
- Department of Molecular Biosciences and Bioengineering, College of Tropical Agriculture and Human Resources, University of Hawai'i, Honolulu, HI 96822, USA
| | - Chino C Cabalteja
- Department of Molecular Biosciences and Bioengineering, College of Tropical Agriculture and Human Resources, University of Hawai'i, Honolulu, HI 96822, USA
| | - Jon-Paul Bingham
- Department of Molecular Biosciences and Bioengineering, College of Tropical Agriculture and Human Resources, University of Hawai'i, Honolulu, HI 96822, USA.
| |
Collapse
|
18
|
Ollivaux C, Soyez D, Toullec JY. Biogenesis of d
-amino acid containing peptides/proteins: where, when and how? J Pept Sci 2014; 20:595-612. [DOI: 10.1002/psc.2637] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 03/13/2014] [Accepted: 03/18/2014] [Indexed: 12/12/2022]
Affiliation(s)
- Céline Ollivaux
- Sorbonne Universités, UPMC Univ Paris 06, UMR 8227; Integrative Biology of Marine Models, Station Biologique de Roscoff; CS 90074, F-29688 Roscoff cedex France
- CNRS, UMR 8227; Integrative Biology of Marine Models, Station Biologique de Roscoff; CS 90074, F-29688 Roscoff cedex France
| | - Daniel Soyez
- Sorbonne Universités, UPMC Univ Paris 06, ER3; Biogenèse des signaux peptidiques; 7 Quai Saint Bernard F-75251 Paris cedex 05 France
- CNRS, ER3; Biogenèse des signaux peptidiques; 7 Quai Saint Bernard F-75251 Paris cedex 05 France
| | - Jean-Yves Toullec
- Sorbonne Universités, UPMC Univ Paris 06, UMR 7144; Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff; CS 90074, F-29688 Roscoff cedex France
- CNRS, UMR 7144; Adaptation et Diversité en Milieu Marin, Station Biologique de Roscoff; CS 90074, F-29688 Roscoff cedex France
| |
Collapse
|
19
|
Latacz G, Kieć-Kononowicz K. Biotransformation of new racemic (R,S)-5-benzylhydantoin derivatives by D-hydantoinases from adzuki bean. BIOCATAL BIOTRANSFOR 2014. [DOI: 10.3109/10242422.2014.893578] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
20
|
Zamora-Bustillos R, Rivera-Reyes R, Aguilar MB, Michel-Morfín E, Landa-Jaime V, Falcón A, Heimer EP. Identification, by RT-PCR, of eight novel I₂-conotoxins from the worm-hunting cone snails Conus brunneus, Conus nux, and Conus princeps from the eastern Pacific (Mexico). Peptides 2014; 53:22-9. [PMID: 24486530 DOI: 10.1016/j.peptides.2014.01.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 01/12/2014] [Accepted: 01/13/2014] [Indexed: 10/25/2022]
Abstract
Marine snails of the genus Conus (∼500 species) are tropical predators that produce venoms for capturing prey, defense and competitive interactions. These venoms contain 50-200 different peptides ("conotoxins") that generally comprise 7-40 amino acid residues (including 0-5 disulfide bridges), and that frequently contain diverse posttranslational modifications, some of which have been demonstrated to be important for folding, stability, and biological activity. Most conotoxins affect voltage- and ligand-gated ion channels, G protein-coupled receptors, and neurotransmitter transporters, generally with high affinity and specificity. Due to these features, several conotoxins are used as molecular tools, diagnostic agents, medicines, and models for drug design. Based on the signal sequence of their precursors, conotoxins have been classified into genetic superfamilies, whereas their molecular targets allow them to be classified into pharmacological families. The objective of this work was to identify and analyze partial cDNAs encoding precursors of conotoxins belonging to I superfamily from three vermivorous species of the Mexican Pacific coast: C. brunneus, C. nux and C. princeps. The precursors identified contain diverse numbers of amino acid residues (C. brunneus, 65 or 71; C. nux, 70; C. princeps, 72 or 73), and all include a highly conserved signal peptide, a C-terminal propeptide, and a mature toxin. All the latter have one of the typical Cys frameworks of the I-conotoxins (C-C-CC-CC-C-C). The prepropeptides belong to the I2-superfamily, and encode eight different hydrophilic and acidic mature toxins, rather similar among them, and some of which have similarity with I2-conotoxins targeting voltage- and voltage-and-calcium-gated potassium channels.
Collapse
Affiliation(s)
- R Zamora-Bustillos
- Laboratorio de Neurofarmacología Marina, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus UNAM Juriquilla, Querétaro 76230, Mexico; Laboratorio de Genética Molecular, Instituto Tecnológico de Conkal, Conkal, Yucatán 97345, Mexico
| | - R Rivera-Reyes
- Laboratorio de Neurofarmacología Marina, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus UNAM Juriquilla, Querétaro 76230, Mexico
| | - M B Aguilar
- Laboratorio de Neurofarmacología Marina, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus UNAM Juriquilla, Querétaro 76230, Mexico.
| | - E Michel-Morfín
- Departamento de Estudios para el Desarrollo Sustentable de Zonas Costeras. CUCSUR-Universidad de Guadalajara, San Patricio-Melaque, Jalisco 48980, Mexico
| | - V Landa-Jaime
- Departamento de Estudios para el Desarrollo Sustentable de Zonas Costeras. CUCSUR-Universidad de Guadalajara, San Patricio-Melaque, Jalisco 48980, Mexico; Posgrado en Ciencias Biológicas y Agropecuarias, Universidad Autónoma de Nayarit, Mexico
| | - A Falcón
- Laboratorio de Neurofarmacología Marina, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus UNAM Juriquilla, Querétaro 76230, Mexico
| | - E P Heimer
- Laboratorio de Neurofarmacología Marina, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus UNAM Juriquilla, Querétaro 76230, Mexico
| |
Collapse
|
21
|
Robinson SD, Safavi-Hemami H, McIntosh LD, Purcell AW, Norton RS, Papenfuss AT. Diversity of conotoxin gene superfamilies in the venomous snail, Conus victoriae. PLoS One 2014; 9:e87648. [PMID: 24505301 PMCID: PMC3914837 DOI: 10.1371/journal.pone.0087648] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Accepted: 12/28/2013] [Indexed: 12/31/2022] Open
Abstract
Animal venoms represent a vast library of bioactive peptides and proteins with proven potential, not only as research tools but also as drug leads and therapeutics. This is illustrated clearly by marine cone snails (genus Conus), whose venoms consist of mixtures of hundreds of peptides (conotoxins) with a diverse array of molecular targets, including voltage- and ligand-gated ion channels, G-protein coupled receptors and neurotransmitter transporters. Several conotoxins have found applications as research tools, with some being used or developed as therapeutics. The primary objective of this study was the large-scale discovery of conotoxin sequences from the venom gland of an Australian cone snail species, Conus victoriae. Using cDNA library normalization, high-throughput 454 sequencing, de novo transcriptome assembly and annotation with BLASTX and profile hidden Markov models, we discovered over 100 unique conotoxin sequences from 20 gene superfamilies, the highest diversity of conotoxins so far reported in a single study. Many of the sequences identified are new members of known conotoxin superfamilies, some help to redefine these superfamilies and others represent altogether new classes of conotoxins. In addition, we have demonstrated an efficient combination of methods to mine an animal venom gland and generate a library of sequences encoding bioactive peptides.
Collapse
Affiliation(s)
- Samuel D. Robinson
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
- * E-mail: (SDR); (HSH)
| | - Helena Safavi-Hemami
- Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Parkville, VIC, Australia
- * E-mail: (SDR); (HSH)
| | - Lachlan D. McIntosh
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, VIC, Australia
| | - Anthony W. Purcell
- Department of Biochemistry and Molecular Biology, Bio21 Institute, University of Melbourne, Parkville, VIC, Australia
| | - Raymond S. Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Anthony T. Papenfuss
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Melbourne, VIC, Australia
| |
Collapse
|
22
|
Abstract
Voltage-gated sodium (Nav) channels are essential contributors to neuronal excitability, making them the most commonly targeted ion channel family by toxins found in animal venoms. These molecules can be used to probe the functional aspects of Nav channels on a molecular level and to explore their physiological role in normal and diseased tissues. This chapter summarizes our existing knowledge of the mechanisms by which animal toxins influence Nav channels as well as their potential application in designing therapeutic drugs.
Collapse
|
23
|
Molecular evolution and diversity of Conus peptide toxins, as revealed by gene structure and intron sequence analyses. PLoS One 2013; 8:e82495. [PMID: 24349297 PMCID: PMC3862624 DOI: 10.1371/journal.pone.0082495] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2013] [Accepted: 10/25/2013] [Indexed: 11/19/2022] Open
Abstract
Cone snails, which are predatory marine gastropods, produce a cocktail of venoms used for predation, defense and competition. The major venom component, conotoxin, has received significant attention because it is useful in neuroscience research, drug development and molecular diversity studies. In this study, we report the genomic characterization of nine conotoxin gene superfamilies from 18 Conus species and investigate the relationships among conotoxin gene structure, molecular evolution and diversity. The I1, I2, M, O2, O3, P, S, and T superfamily precursors all contain three exons and two introns, while A superfamily members contain two exons and one intron. The introns are conserved within a certain gene superfamily, and also conserved across different Conus species, but divergent among different superfamilies. The intronic sequences contain many simple repeat sequences and regulatory elements that may influence conotoxin gene expression. Furthermore, due to the unique gene structure of conotoxins, the base substitution rates and the number of positively selected sites vary greatly among exons. Many more point mutations and trinucleotide indels were observed in the mature peptide exon than in the other exons. In addition, the first example of alternative splicing in conotoxin genes was found. These results suggest that the diversity of conotoxin genes has been shaped by point mutations and indels, as well as rare gene recombination or alternative splicing events, and that the unique gene structures could have made a contribution to the evolution of conotoxin genes.
Collapse
|
24
|
Incorporation of post-translational modified amino acids as an approach to increase both chemical and biological diversity of conotoxins and conopeptides. Amino Acids 2013; 46:125-51. [DOI: 10.1007/s00726-013-1606-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Accepted: 10/17/2013] [Indexed: 02/06/2023]
|
25
|
Fedosov AÉ, Moshkovskiĭ SA, Kuznetsova KG, Olivera BM. [Conotoxins: from the biodiversity of gastropods to new drugs]. BIOMEDIT︠S︡INSKAI︠A︡ KHIMII︠A︡ 2013; 59:267-94. [PMID: 23987066 DOI: 10.18097/pbmc20135903267] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A review describes general trends in research of conotoxins that are peptide toxins isolated from sea gastropods of the Conus genus, since the toxins were discovered in 1970th. There are disclosed a conotoxin classification, their structure diversity and different ways of action to their molecular targets, mainly, ion channels. In the applied aspect of conotoxin research, drug discovery and development is discussed, the drugs being based on conotoxin structure. A first exemplary drug is a ziconotide, which is an analgesic of new generation.
Collapse
|
26
|
Rong M, Duan Z, Chen J, Li J, Xiao Y, Liang S. Native pyroglutamation of huwentoxin-IV: a post-translational modification that increases the trapping ability to the sodium channel. PLoS One 2013; 8:e65984. [PMID: 23826086 PMCID: PMC3691182 DOI: 10.1371/journal.pone.0065984] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 04/29/2013] [Indexed: 11/23/2022] Open
Abstract
Huwentoxin-IV (HWTX-IV), a tetrodotoxin-sensitive (TTX-s) sodium channel antagonist, is found in the venom of the Chinese spider Ornithoctonus huwena. A naturally modified HWTX-IV (mHWTX-IV), having a molecular mass 18 Da lower than HWTX-IV, has also been isolated from the venom of the same spider. By a combination of enzymatic fragmentation and MS/MS de novo sequencing, mHWTX-IV has been shown to have the same amino acid sequence as that of HWTX-IV, except that the N-terminal glutamic acid replaced by pyroglutamic acid. mHWTX-IV inhibited tetrodotoxin-sensitive voltage-gated sodium channels of dorsal root ganglion neurons with an IC50 nearly equal to native HWTX-IV. mHWTX-IV showed the same activation and inactivation kinetics seen for native HWTX-IV. In contrast with HWTX-IV, which dissociates at moderate voltage depolarization voltages (+50 mV, 180000 ms), mHWTX-IV inhibition of TTX-sensitive sodium channels is not reversed by strong depolarization voltages (+200 mV, 500 ms). Recovery of Nav1.7current was voltage-dependent and was induced by extreme depolarization in the presence of HWTX-IV, but no obvious current was elicited after application of mHWTX-IV. Our data indicate that the N-terminal modification of HWTX-IV gives the peptide toxin a greater ability to trap the voltage sensor in the sodium channel. Loss of a negative charge, caused by cyclization at the N-terminus, is a possible reason why the modified toxin binds much stronger. To our knowledge, this is the first report of a pyroglutamic acid residue in a spider toxin; this modification seems to increase the trapping ability of the voltage sensor in the sodium channel.
Collapse
Affiliation(s)
- Mingqiang Rong
- The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences and Yunnan Province, Kunming Institute of Zoology, Kunming, Yunnan, China
| | - Zhigui Duan
- The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Juliang Chen
- The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Jianglin Li
- The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Yuchen Xiao
- The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Songping Liang
- The Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha, China
- * E-mail:
| |
Collapse
|
27
|
Morishita F, Furukawa Y, Matsushima O. Molecular cloning of two distinct precursor genes of NdWFamide, a d-tryptophan-containing neuropeptide of the sea hare, Aplysia kurodai. Peptides 2012; 38:291-301. [PMID: 23000476 DOI: 10.1016/j.peptides.2012.08.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Revised: 08/22/2012] [Accepted: 08/22/2012] [Indexed: 10/27/2022]
Abstract
NdWFamide (NdWFa) is a D-tryptophan-containing cardioexcitatory neuropeptide in gastropod mollusks, such as Aplysia kurodai and Lymanea stagnalis. In this study, we have cloned two cDNA encoding distinct precursors for NdWFa from the abdominal ganglion of A. kurodai. One of the predicted precursor proteins consisted of 90 amino acids (NWF90), and the other consisted of 87 amino acids (NWF87). Both of the predicted precursor proteins have one NWFGKR sequence preceded by the N-terminal signal peptide. Sequential double staining by in situ hybridization (ISH) and immunostaining with anti-NdWFa antibody suggested that NdWFa-precursor and NdWFa peptide co-exist in neurons located in the right-upper quadrant region of the abdominal ganglion. In ISH, NWF90-specific signal and NWF87-specific one were found in different subsets of neurons in the abdominal ganglia of Aplysia. The expression level of NWF90 gene estimated by RT-PCR is much higher than that of NWF87 gene. These results suggest that NWF90 precursor is the major source of NdWFa in Aplysia ganglia.
Collapse
Affiliation(s)
- Fumihiro Morishita
- Department of Biological Science, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan.
| | | | | |
Collapse
|
28
|
Quinton L, Gilles N, Smargiasso N, Kiehne A, De Pauw E. An unusual family of glycosylated peptides isolated from Dendroaspis angusticeps venom and characterized by combination of collision induced and electron transfer dissociation. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2011; 22:1891-1897. [PMID: 21952754 DOI: 10.1007/s13361-011-0210-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 06/30/2011] [Accepted: 07/05/2011] [Indexed: 05/31/2023]
Abstract
This study describes the structural characterization of a totally new family of peptides from the venom of the snake green mamba (Dendroaspis angusticeps). Interestingly, these peptides differ in several points from other already known mamba toxins. First of all, they exhibit very small molecular masses, ranging from 1.3 to 2.4 kDa. The molecular mass of classical mamba toxins is in the range of 7 to 25 kDa. Second, the new peptides do not contain disulfide bonds, a post-translational modification commonly encountered in animal toxins. The third difference is the very high proportion of proline residues in the sequence accounting for about one-third of the sequence. Finally, these new peptides reveal a carbohydrate moiety, indicating a glycosylation in the sequence. The last two features have made the structural characterization of the new peptides by mass spectrometry a real analytical challenge. Peptides were characterized by a combined use of MALDI- TOF/TOF and nanoESI-IT-ETD experiments to determine not only the peptide sequence but also the composition and the position of the carbohydrate moiety. Anyway, such small glycosylated and proline-rich toxins are totally different from any other known snake peptide and form, as a consequence, a new family of peptides.
Collapse
Affiliation(s)
- Loïc Quinton
- Laboratoire de spectrométrie de masse, Département de Chimie-GIGA-R, Université de Liège, Liège 4000, Belgium.
| | | | | | | | | |
Collapse
|
29
|
Gehmayr V, Mollay C, Reith L, Müller N, Jilek A. Tight binding of transition-state analogues to a peptidyl-aminoacyl-L/D-isomerase from frog skin. Chembiochem 2011; 12:1996-2000. [PMID: 21739559 PMCID: PMC3195878 DOI: 10.1002/cbic.201100203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Indexed: 11/30/2022]
Affiliation(s)
- Verena Gehmayr
- Institute of Organic Chemistry, Johannes Kepler University LinzAltenberger Strasse 69, 4040 Linz (Austria)
| | - Christa Mollay
- Institute of Molecular Biology, Austrian Academy of SciencesBillrothstrasse 11, 5020 Salzburg (Austria)
| | - Lorenz Reith
- Institute of Organic Chemistry, Johannes Kepler University LinzAltenberger Strasse 69, 4040 Linz (Austria)
| | - Norbert Müller
- Institute of Organic Chemistry, Johannes Kepler University LinzAltenberger Strasse 69, 4040 Linz (Austria)
| | - Alexander Jilek
- Chair of Bioinformatics, Department of Biotechnology, University of Natural Resources and Life SciencesMuthgasse 18, 1190 Vienna (Austria)
- Institute of Organic Chemistry, Johannes Kepler University LinzAltenberger Strasse 69, 4040 Linz (Austria)
- Institute of Molecular Biology, Austrian Academy of SciencesBillrothstrasse 11, 5020 Salzburg (Austria)
| |
Collapse
|
30
|
Jilek A, Mollay C, Lohner K, Kreil G. Substrate specificity of a peptidyl-aminoacyl-L/D-isomerase from frog skin. Amino Acids 2011; 42:1757-64. [PMID: 21424715 PMCID: PMC3325411 DOI: 10.1007/s00726-011-0890-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Accepted: 03/09/2011] [Indexed: 12/14/2022]
Abstract
In the skin of fire-bellied toads (Bombina species), an aminoacyl-l/d-isomerase activity is present which catalyses the post-translational isomerization of the l- to the d-form of the second residue of its substrate peptides. Previously, this new type of enzyme was studied in some detail and genes potentially coding for similar polypeptides were found to exist in several vertebrate species including man. Here, we present our studies to the substrate specificity of this isomerase using fluorescence-labeled variants of the natural substrate bombinin H with different amino acids at positions 1, 2 or 3. Surprisingly, this enzyme has a rather low selectivity for residues at position 2 where the change of chirality at the alpha-carbon takes place. In contrast, a hydrophobic amino acid at position 1 and a small one at position 3 of the substrate are essential. Interestingly, some peptides containing a Phe at position 3 also were substrates. Furthermore, we investigated the role of the amino-terminus for substrate recognition. In view of the rather broad specificity of the frog isomerase, we made a databank search for potential substrates of such an enzyme. Indeed, numerous peptides of amphibia and mammals were found which fulfill the requirements determined in this study. Expression of isomerases with similar characteristics in other species can therefore be expected to catalyze the formation of peptides containing d-amino acids.
Collapse
Affiliation(s)
- Alexander Jilek
- Institute of Organic Chemistry, Johannes Kepler University Linz, Altenberger Str. 69, 4040, Linz, Austria.
| | | | | | | |
Collapse
|
31
|
Bai L, Romanova EV, Sweedler JV. Distinguishing endogenous D-amino acid-containing neuropeptides in individual neurons using tandem mass spectrometry. Anal Chem 2011; 83:2794-800. [PMID: 21388150 DOI: 10.1021/ac200142m] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
RNA-based protein synthesis produces L-amino acid-containing proteins and peptides. D-amino acid-containing peptides (DAACPs) can be generated from L-amino acid peptides via post-translational modification. In the nervous system, the conformational change of a single L-amino acid in a peptide to its D-form results in altered bioactivity, with some DAACPs having orders-of-magnitude enhanced efficacy. However, this modification is often overlooked when characterizing endogenous peptides. Here, with the use of matrix-assisted laser desorption ionization (MALDI) time-of-flight (TOF)/TOF mass spectrometry, neuropeptides that have the second residue isomerized to the D-isoform are distinguished from their L-epimers via differences in the relative amounts of specific fragment ions during tandem MS. With the appropriate fragment ions chosen, and in some cases with the use of metal adducts, epimer discrimination is optimized. Specifically, the cardioexcitatory peptide Asn-(D)Trp-Phe-amide (NdWFa) was assayed directly from neurons isolated from the sea slug Aplysia californica; the fraction of the peptide with the second residue (W) in the D- versus L-form was 90 ± 10%. We demonstrate that this approach is well suited for confirming DAACPs directly from cells and tissue, advancing our understanding of the l to d modification and the role it plays in cell-to-cell signaling.
Collapse
Affiliation(s)
- Lu Bai
- Department of Molecular and Integrative Physiology, University of Illinois, Urbana, Illinois 61801, USA
| | | | | |
Collapse
|
32
|
Liu Z, Yu Z, Liu N, Zhao C, Hu J, Dai Q. cDNA cloning of conotoxins with framework XII from several Conus species. Acta Biochim Biophys Sin (Shanghai) 2010; 42:656-61. [PMID: 20732855 DOI: 10.1093/abbs/gmq066] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In our efforts for cloning novel I(2)-superfamily conotoxins using the signal peptide sequence, we identified a novel conotoxin Lt12.4 from Conus litteratus. This gene has a framework XII (-C-C-C-C-CC-C-C-), which is distinct from the cysteine pattern I(2)-superfamily conotoxin (-C-C-CC-CC-C-C-). Subsequently, we found the signal peptide sequence of Lt12.4 by 5'-RACE. Using this new sequence, we identified another five novel conotoxins with this cysteine pattern from four Conus species (Conus eburneus, Conus imperialis, Conus marmoreus, and C. litteratus). These novel conotoxins have the same cysteine pattern as the reported Gla-TxX and Gla-MII, and may contain Gla residues. Furthermore, they have the highly conserved signal peptide and hypervariable mature peptide sequences, and widely exist in Conus species. Therefore, it could be defined as a new superfamily of E-conotoxins.
Collapse
Affiliation(s)
- Zhuguo Liu
- Beijing Institute of Biotechnology, China
| | | | | | | | | | | |
Collapse
|
33
|
Aguilar MB, Pérez-Reyes LI, López Z, de la Cotera EPH, Falcón A, Ayala C, Galván M, Salvador C, Escobar LI. Peptide sr11a from Conus spurius is a novel peptide blocker for Kv1 potassium channels. Peptides 2010; 31:1287-91. [PMID: 20403399 DOI: 10.1016/j.peptides.2010.04.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Revised: 04/12/2010] [Accepted: 04/12/2010] [Indexed: 12/22/2022]
Abstract
More than a hundred conotoxins are known today and from them, only seven conopeptides have been identified to target voltage-gated potassium channels (Kv). Conotoxin sr11a belongs to the I(2)-superfamily which is characterized by four disulfide bridges and provokes muscle stiffness when injected intracranially in mice. The aim of this work was to test the biological activity of sr11a on recombinant voltage-gated Kv1 potassium channels expressed in Xenopus laevis oocytes. Peptide sr11a was purified by high-performance liquid chromatography from the venom of the vermivorous Conus spurius. We found that peptide sr11a inhibits the delayed rectifiers Kv1.2 and Kv1.6 but had not effect on the slowly inactivating Kv1.3 channel. The functional dyad composed of a basic Lys and a hydrophobic amino acid residue is a crucial structural element, regarding the binding properties and blocking activities of more than a hundred K(+) channel toxins. Peptide sr11a does not contain Lys residues and then, it lacks the functional dyad. Molecular modeling of peptide sr11a reveals the presence of exposed basic residues of Arg and suggests that Arg17 and Arg29 are important on its biological activity.
Collapse
Affiliation(s)
- Manuel B Aguilar
- Laboratorio de Neurofarmacología Marina, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro 76230, Mexico
| | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Martínez-Rodríguez S, Martínez-Gómez A, Rodríguez-Vico F, Clemente-Jiménez J, Las Heras-Vázquez F. Natural Occurrence and Industrial Applications of d-Amino Acids: An Overview. Chem Biodivers 2010; 7:1531-48. [DOI: 10.1002/cbdv.200900245] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
35
|
Kaas Q, Westermann JC, Craik DJ. Conopeptide characterization and classifications: an analysis using ConoServer. Toxicon 2010; 55:1491-509. [PMID: 20211197 DOI: 10.1016/j.toxicon.2010.03.002] [Citation(s) in RCA: 160] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Revised: 02/25/2010] [Accepted: 03/01/2010] [Indexed: 10/19/2022]
Abstract
Cone snails are carnivorous marine gastropods that have evolved potent venoms to capture their prey. These venoms comprise a rich and diverse cocktail of peptide toxins, or conopeptides, whose high diversity has arisen from an efficient hypermutation mechanism, combined with a high frequency of post-translational modifications. Conopeptides bind with high specificity to distinct membrane receptors, ion channels, and transporters of the central and muscular nervous system. As well as serving their natural function in prey capture, conopeptides have been utilized as versatile tools in neuroscience and have proven valuable as drug leads that target the nervous system in humans. This paper examines current knowledge on conopeptide sequences based on an analysis of gene and peptide sequences in ConoServer (http://www.conoserver.org), a specialized database of conopeptide sequences and three-dimensional structures. We describe updates to the content and organization of ConoServer and discuss correlations between gene superfamilies, cysteine frameworks, pharmacological families targeted by conopeptides, and the phylogeny, habitat, and diet of cone snails. The study identifies gaps in current knowledge of conopeptides and points to potential directions for future research.
Collapse
Affiliation(s)
- Quentin Kaas
- The University of Queensland, Institute for Molecular Bioscience, Division of Chemistry and Structural Biology, Brisbane, 4072 QLD, Australia
| | | | | |
Collapse
|
36
|
Zamora-Bustillos R, Aguilar MB, Falcón A. Identification, by molecular cloning, of a novel type of I2-superfamily conotoxin precursor and two novel I2-conotoxins from the worm-hunter snail Conus spurius from the Gulf of México. Peptides 2010; 31:384-93. [PMID: 19836429 DOI: 10.1016/j.peptides.2009.10.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Revised: 10/03/2009] [Accepted: 10/06/2009] [Indexed: 11/24/2022]
Abstract
cDNA was prepared from the venom duct of a single Conus spurius specimen collected near the coast of Campeche, México. From it, PCR products were generated aiming to clone I-conotoxin precursors. Thirty clones were sequenced and predicted to encode ten distinct precursors: seven of I(2)-conotoxins and three of I(2)-like-conotoxins. These precursors contain three different, mature toxins, sr11a, sr11b and sr11c, of which two are novel and one (sr11a) has been previously purified and characterized from the venom of this species. The precursors include a 26- (I(2)) or 23- residue signal peptide (I(2)-like), a 31-residue "pro" region (I(2)-like), and a 32-residue mature toxin region (I(2) and I(2)-like). In addition, all the precursors have a 13-residue "post" region which contains a gamma-carboxylation recognition sequence that directs the gamma-carboxylation of Glu-9 and Glu-10 of toxin sr11a and, possibly, Glu-13 of toxin sr11b and Glu-9 of toxin sr11c. This is the first time that a "post" region has been found in precursors of I-conotoxins that also contain a "pro" region. The "post" peptide is enzymatically processed to yield the amidated mature toxin sr11a, which implies that gamma-carboxylation occurs before amidation. Phylogenetic analysis at the whole precursor level indicates that the I(2)-like-conotoxins of C. spurius are more related to I(2)-conotoxins than to I(1)- and I(3)-conotoxins from other species, and that they might represent a new subgroup of the I(2)-superfamily. The three I-conotoxins from C. spurius have charge differences at seven to nine positions, suggesting that they might have different molecular target types or subtypes.
Collapse
Affiliation(s)
- Roberto Zamora-Bustillos
- Laboratorio de Neurofarmacología Marina, Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro 76230, Mexico
| | | | | |
Collapse
|
37
|
Liu Z, Xu N, Hu J, Zhao C, Yu Z, Dai Q. Identification of novel I-superfamily conopeptides from several clades of Conus species found in the South China Sea. Peptides 2009; 30:1782-7. [PMID: 19595726 DOI: 10.1016/j.peptides.2009.06.036] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Revised: 06/26/2009] [Accepted: 06/26/2009] [Indexed: 11/20/2022]
Abstract
The I-superfamily of Conus peptides represents a new class of peptides with four disulfide bridges (-C-C-CC-CC-C-C-) that falls into three (I1, I2 and I3) categories according to the different signal peptide sequences. The I-superfamily has received increasing attention because it targets K+ ion channels, a function that is relatively rare in conotoxins. Herein we report 11 novel I-superfamily conotoxins from the venom ducts of five Cone snails (Conus eburneus, Conus imperialis, Conus vitulinus, Conus emaciatus and Conus litteratus) native to the South China Sea using a primer designed according to the N-terminus of the signal sequence of I2-superfamily conotoxins. The alignment of sequences revealed that signal regions exhibited moderate conservation with the exception of Eb11.3 from C. eburneus with homologies of 21.1%, 38.5% and 30.0% to the signal peptides of I1, I2 and I3 superfamily conotoxins, respectively. The mature peptides ranged from almost identical to highly divergent between species. Analyses of the evolutionary trees of these peptides with those of reported I-superfamily conotoxins showed that nine of them fall in I2 superfamily clades, but two of them were neither I1- and I2- nor I3-superfamily clades. Notably, some peptides exhibited significantly different amino acid residues in the intercysteine loops compared with group A, B and C of I-superfamily conopeptides, suggesting that they may have different bioactivities and functions.
Collapse
Affiliation(s)
- Zhuguo Liu
- Beijing Institute of Biotechnology, Beijing 100071, People's Republic of China
| | | | | | | | | | | |
Collapse
|
38
|
Abstract
Venomous marine cone snails harbour a variety of small disulfide-rich peptides called conotoxins, which target a broad range of ion channels, membrane receptors, and transporters. More than 700 species of Conus are thought to exist, each expressing a wide array of different peptides. Within this large repertoire of toxins, individual conotoxins are able to discriminate between different subtypes and isoforms of ion channels, making them valuable pharmacological probes or leads for drug design. This review gives a brief background to the discovery of conotoxins and describes their sequences, biological activities, and applications in drug design.
Collapse
Affiliation(s)
- Reena Halai
- The University of Queensland, Institute for Molecular Bioscience, Brisbane, Queensland 4072, Australia
| | | |
Collapse
|
39
|
Bai L, Sheeley S, Sweedler JV. Analysis of Endogenous D-Amino Acid-Containing Peptides in Metazoa. ACTA ACUST UNITED AC 2009; 1:7-24. [PMID: 20490347 DOI: 10.1007/s12566-009-0001-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Peptides are chiral molecules with their structure determined by the composition and configuration of their amino acid building blocks. The naturally occurring amino acids, except glycine, possess two chiral forms. This allows the formation of multiple peptide diastereomers that have the same sequence. Although living organisms use L-amino acids to make proteins, a group of D-amino acid-containing peptides (DAACPs) has been discovered in animals that have at least one of their residues isomerized to the D-form via an enzyme-catalyzed process. In many cases, the biological functions of these peptides are enhanced due to this structural conversion. These DAACPs are different from those known to occur in bacterial cell wall and antibiotic peptides, the latter of which are synthesized in a ribosome-independent manner. DAACPs have now also been identified in a number of distinct groups throughout the Metazoa. Their serendipitous discovery has often resulted from discrepancies observed in bioassays or in chromatographic behavior between natural peptide fractions and peptides synthesized according to a presumed all-L sequence. Because this L-to-D post-translational modification is subtle and not detectable by most sequence determination approaches, it is reasonable to suspect that many studies have overlooked this change; accordingly, DAACPs may be more prevalent than currently thought. Although diastereomer separation techniques developed with synthetic peptides in recent years have greatly aided in the discovery of natural DAACPs, there is a need for new, more robust methods for naturally complex samples. In this review, a brief history of DAACPs in animals is presented, followed by discussion of a variety of analytical methods that have been used for diastereomeric separation and detection of peptides.
Collapse
Affiliation(s)
- Lu Bai
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
| | | | | |
Collapse
|
40
|
Yuan DD, Liu L, Shao XX, Peng C, Chi CW, Guo ZY. New conotoxins define the novel I3-superfamily. Peptides 2009; 30:861-5. [PMID: 19428762 DOI: 10.1016/j.peptides.2009.01.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 01/20/2009] [Accepted: 01/21/2009] [Indexed: 11/29/2022]
Abstract
We purified two novel conotoxins, designated as ca11a and ca11b, from the venom of Conus caracteristicus. Based on the amino acid sequence of mature ca11a, we cloned its full-length cDNA. Based on the signal peptide of ca11a, several ca11a-like conotoxins were cloned from C. caracteristicus and C. pulicarius. These novel conotoxins have an I-superfamily cysteine pattern but with a novel signal peptide sequence, suggesting they belong to a new branch of I-superfamily, designated as I(3)-superfamily. Additionally, two O-superfamily conotoxins were also cloned based on the signal peptide of ca11a, suggesting a possible evolutionary relationship between O- and I-superfamilies.
Collapse
Affiliation(s)
- Duo-Duo Yuan
- Institute of Protein Research, College of Life Sciences and Technology, Tongji University, Shanghai, PR China
| | | | | | | | | | | |
Collapse
|
41
|
Loughnan ML, Nicke A, Lawrence N, Lewis RJ. Novel αD-Conopeptides and Their Precursors Identified by cDNA Cloning Define the D-Conotoxin Superfamily. Biochemistry 2009; 48:3717-29. [DOI: 10.1021/bi9000326] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Marion L. Loughnan
- Institute for Molecular Biosciences, The University of Queensland, Brisbane, Qld 4072, Australia, and Max Planck Institute for Brain Research, Deutschordenstrasse 46, 60528 Frankfurt/Main, Germany
| | - Annette Nicke
- Institute for Molecular Biosciences, The University of Queensland, Brisbane, Qld 4072, Australia, and Max Planck Institute for Brain Research, Deutschordenstrasse 46, 60528 Frankfurt/Main, Germany
| | - Nicole Lawrence
- Institute for Molecular Biosciences, The University of Queensland, Brisbane, Qld 4072, Australia, and Max Planck Institute for Brain Research, Deutschordenstrasse 46, 60528 Frankfurt/Main, Germany
| | - Richard J. Lewis
- Institute for Molecular Biosciences, The University of Queensland, Brisbane, Qld 4072, Australia, and Max Planck Institute for Brain Research, Deutschordenstrasse 46, 60528 Frankfurt/Main, Germany
| |
Collapse
|
42
|
Yuan DD, Liu L, Shao XX, Peng C, Chi CW, Guo ZY. Isolation and cloning of a conotoxin with a novel cysteine pattern from Conus caracteristicus. Peptides 2008; 29:1521-5. [PMID: 18584917 DOI: 10.1016/j.peptides.2008.05.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2008] [Revised: 05/13/2008] [Accepted: 05/16/2008] [Indexed: 11/21/2022]
Abstract
A new conotoxin, ca16a, containing 8 cysteine residues was purified, sequenced, and cloned from a worm-hunting snail, Conus caracteristicus. This conotoxin is an extremely hydrophilic peptide comprising 34 residues, with 4 acidic and 4 basic residues. It is rich in polar Gly, Ser, and Thr residues and includes a hydroxylated Pro residue. The cysteine arrangement pattern of ca16a (-C-C-CC-C-CC-C-, designated as framework #16) is distinct from that of other known conotoxins. Furthermore, the signal peptide sequence of this conotoxin does not share any homology with those of other conotoxins. Leu residues account for almost 50% of its 20-residue signal peptide. The unique cysteine framework and signal peptide sequence of ca16a suggest that it belongs to a new conotoxin superfamily.
Collapse
Affiliation(s)
- Duo-Duo Yuan
- Institute of Protein Research, College of Life Sciences and Technology, Tongji University, 1239 Siping Road, Shanghai 200092, PR China
| | | | | | | | | | | |
Collapse
|
43
|
Peng C, Liu L, Shao X, Chi C, Wang C. Identification of a novel class of conotoxins defined as V-conotoxins with a unique cysteine pattern and signal peptide sequence. Peptides 2008; 29:985-91. [PMID: 18304695 DOI: 10.1016/j.peptides.2008.01.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2007] [Revised: 01/10/2008] [Accepted: 01/11/2008] [Indexed: 11/27/2022]
Abstract
Cone snails are predatory gastropod mollusks distributed in all tropical marine habitats with a highly sophisticated defense strategy using small peptides in their venoms. Here, we report the discovery and initial characterization of the V-superfamily conotoxins. A novel conotoxin vi15a was purified from the venom of a worm-hunting species Conus virgo. The sequence of vi15a was determined to have a unique arrangement of cysteine residues (C-C-CC-C-C-C-C), which defines the new V-superfamily conotoxins. The cDNA of vi15a was cloned with RACE method. Its unique signal peptide sequence led to the cloning of another V-superfamily conotoxin, Vt15.1, from Conus vitulinus. These results, as well as the existence of Lt15.1 from Conus litteratus and ca15a from Conus caracteristicus with the same cysteine pattern, suggest that V-superfamily might be a large and diverse group of peptides widely distributed in different Conus species. Like other eight Cys-containing toxins, V-superfamily conotoxins might also adopt an "ICK+1" disulfide bond connectivity. The identification of this novel class of conotoxins will certainly improve our understanding of the structure diversity of disulfide rich toxins.
Collapse
Affiliation(s)
- Can Peng
- Institute of Protein Research, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | | | | | | | | |
Collapse
|
44
|
Fiedler B, Zhang MM, Buczek O, Azam L, Bulaj G, Norton RS, Olivera BM, Yoshikami D. Specificity, affinity and efficacy of iota-conotoxin RXIA, an agonist of voltage-gated sodium channels Na(V)1.2, 1.6 and 1.7. Biochem Pharmacol 2008; 75:2334-44. [PMID: 18486102 DOI: 10.1016/j.bcp.2008.03.019] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Revised: 03/28/2008] [Accepted: 03/31/2008] [Indexed: 12/19/2022]
Abstract
The excitotoxic conopeptide iota-RXIA induces repetitive action potentials in frog motor axons and seizures upon intracranial injection into mice. We recently discovered that iota-RXIA shifts the voltage-dependence of activation of voltage-gated sodium channel Na(V)1.6 to a more hyperpolarized level. Here, we performed voltage-clamp experiments to examine its activity against rodent Na(V)1.1 through Na(V)1.7 co-expressed with the beta1 subunit in Xenopus oocytes and Na(V)1.8 in dissociated mouse DRG neurons. The order of sensitivity to iota-RXIA was Na(V)1.6 > 1.2 > 1.7, and the remaining subtypes were insensitive. The time course of iota-RXIA-activity on Na(V)1.6 during exposure to different peptide concentrations were well fit by single-exponential curves that provided k(obs). The plot of k(obs)versus [iota-RXIA] was linear, consistent with a bimolecular reaction with a K(d) of approximately 3 microM, close to the steady-state EC(50) of approximately 2 microM. iota-RXIA has an unusual residue, D-Phe, and the analog with an L-Phe instead, iota-RXIA[L-Phe44], had a two-fold lower affinity and two-fold faster off-rate than iota-RXIA on Na(V)1.6 and furthermore was inactive on Na(V)1.2. iota-RXIA induced repetitive action potentials in mouse sciatic nerve with conduction velocities of both A- and C-fibers, consistent with the presence of Na(V)1.6 at nodes of Ranvier as well as in unmyelinated axons. Sixteen peptides homologous to iota-RXIA have been identified from a single species of Conus, so these peptides represent a rich family of novel sodium channel-targeting ligands.
Collapse
Affiliation(s)
- Brian Fiedler
- Department of Biology, University of Utah, Salt Lake City, Utah 84112, USA
| | | | | | | | | | | | | | | |
Collapse
|
45
|
Two different groups of signal sequence in M-superfamily conotoxins. Toxicon 2008; 51:813-22. [DOI: 10.1016/j.toxicon.2007.12.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2007] [Revised: 12/07/2007] [Accepted: 12/07/2007] [Indexed: 11/23/2022]
|
46
|
Han Y, Huang F, Jiang H, Liu L, Wang Q, Wang Y, Shao X, Chi C, Du W, Wang C. Purification and structural characterization of a d-amino acid-containing conopeptide, conomarphin, from Conus marmoreus. FEBS J 2008; 275:1976-87. [DOI: 10.1111/j.1742-4658.2008.06352.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|
47
|
Ewing MA, Wang J, Sheeley SA, Sweedler JV. Detecting D-amino acid-containing neuropeptides using selective enzymatic digestion. Anal Chem 2008; 80:2874-80. [PMID: 18341354 DOI: 10.1021/ac7025173] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Neuropeptides, gene products that undergo extensive post-translational modification (PTM), are frequently characterized using mass spectrometry (MS). One PTM in particular, the conversion of an L-amino acid to a D-amino acid, has no associated mass shift. Therefore, this PTM is difficult to evaluate using MS alone, especially in complex peptide mixtures. Here, enzymatic digestion using microsomal alanyl aminopeptidase is combined with MS characterization. This enzyme selectively degrades peptides lacking a D-amino acid in the second position from the N-terminus. By comparing a sample before and after digestion, D-amino acid-containing peptides (DAACPs) present in small quantities in a complex mixture can be identified, even among much larger quantities of other non-DAACPs. Protocols that use microsomal alanyl aminopeptidase as a discovery-enabling agent are described and validated by identifying a known DAACP from the Aplysia californica abdominal ganglion.
Collapse
Affiliation(s)
- Michael A Ewing
- Department of Chemistry and the Beckman Institute, University of Illinois, Urbana, Illinois 61801, USA
| | | | | | | |
Collapse
|
48
|
Identification of a novel S-superfamily conotoxin from vermivorous Conus caracteristicus. Toxicon 2008; 51:1331-7. [PMID: 18423793 DOI: 10.1016/j.toxicon.2008.03.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2007] [Revised: 02/27/2008] [Accepted: 03/03/2008] [Indexed: 11/21/2022]
Abstract
Conotoxins have been classified into several different superfamilies based on the highly conserved signal peptide sequences of their precursors. However, little is known about the five disulfide bonds containing S-superfamily conotoxins. Only two S-superfamily conotoxins have been identified but their cDNAs are not reported. In this work, we identified a novel S-superfamily conotoxin ca8a from vermivorous Conus caracteristicus. Its sequence shares no homology with those of two other previously reported toxins of the same superfamily, but they have the same cysteine framework, in particular the CX(3)CXC-CXC-CXCXC pattern at the C-terminal part. This implies that these toxins might have the same spatial scaffold, but different local conformation or residue side chains may be the cause of their different biological functions. Furthermore, the cDNA of ca8a was cloned with the RACE method. ca8a has a signal peptide sequence different from those of other conotoxins. This gives a defining feature of S-superfamily conotoxins and led to the cloning of more S-superfamily conotoxins from cone snails of different prey types, which indicates that S-superfamily conotoxins widely exist. These results will certainly enrich our understanding of the highly diversified S-superfamily conotoxins.
Collapse
|
49
|
Lopez-Vera E, Walewska A, Skalicky JJ, Olivera BM, Bulaj G. Role of Hydroxyprolines in the in Vitro Oxidative Folding and Biological Activity of Conotoxins. Biochemistry 2008; 47:1741-51. [DOI: 10.1021/bi701934m] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Estuardo Lopez-Vera
- Department of Biology, Department of Medicinal Chemistry, and Department of Biochemistry, University of Utah, Salt Lake City, Utah 84108, and Faculty of Chemistry, University of Gdansk, 80-952 Gdansk, Poland
| | - Aleksandra Walewska
- Department of Biology, Department of Medicinal Chemistry, and Department of Biochemistry, University of Utah, Salt Lake City, Utah 84108, and Faculty of Chemistry, University of Gdansk, 80-952 Gdansk, Poland
| | - Jack J. Skalicky
- Department of Biology, Department of Medicinal Chemistry, and Department of Biochemistry, University of Utah, Salt Lake City, Utah 84108, and Faculty of Chemistry, University of Gdansk, 80-952 Gdansk, Poland
| | - Baldomero M. Olivera
- Department of Biology, Department of Medicinal Chemistry, and Department of Biochemistry, University of Utah, Salt Lake City, Utah 84108, and Faculty of Chemistry, University of Gdansk, 80-952 Gdansk, Poland
| | - Grzegorz Bulaj
- Department of Biology, Department of Medicinal Chemistry, and Department of Biochemistry, University of Utah, Salt Lake City, Utah 84108, and Faculty of Chemistry, University of Gdansk, 80-952 Gdansk, Poland
| |
Collapse
|
50
|
|