Diversity and Pharmacological Discovery from Venoms of Conus and other Conidaeans

A special issue of Toxins (ISSN 2072-6651). This special issue belongs to the section "Animal Venoms".

Deadline for manuscript submissions: closed (30 April 2019) | Viewed by 15712

Special Issue Editors

Departments of Biology and Biochemistry, University of Utah, Salt Lake City, UT 84112, USA
Departments of Biology and Biochemistry, University of Utah, Salt Lake City, UT 84112, USA

Special Issue Information

Dear Colleagues,

The gastropod superfamily Conoidea comprises at least 10,000 extant species (some estimates go to 40,000 species) representing one of the most biodiverse lineages of venomous animals. Although cone snails (family Conidae) have been extensively investigated, the venoms of other species that belong to the Conoidean families remain largely uncharacterized. These include the auger snails (family Terebridae) and the diverse families collectively known as turrids.

This Special Issue focuses on the large, and mostly unexplored, biodiversity of species in the Conoidean superfamily and the present state of knowledge regarding the extraordinary diversity of toxins they produce. Specifically, an overview of Conoidean venoms and their biomedical applications will be provided and, by highlighting new findings on the discovery and pharmacology of Conoidean venom peptides, we will discuss why the outlook for future discoveries appears exceptionally promising.

Prof. Dr. Baldomero Olivera
Dr. Helena Safavi-Hemami
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a double-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Toxins is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Venoms
  • Conoidea
  • Biodiversity
  • Marine natural products
  • Cone snails
  • Auger Snails
  • Turrids
  • Conopeptides
  • Non-opioid analgesic

Published Papers (4 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

14 pages, 2525 KiB  
Article
αD-Conotoxins in Species of the Eastern Pacific: The Case of Conus princeps from Mexico
by Arisaí C. Hernández-Sámano, Andrés Falcón, Fernando Zamudio, César V.F. Batista, Jesús Emilio Michel-Morfín, Víctor Landa-Jaime, Estuardo López-Vera, Michael C. Jeziorski and Manuel B. Aguilar
Toxins 2019, 11(7), 405; https://doi.org/10.3390/toxins11070405 - 12 Jul 2019
Cited by 4 | Viewed by 2924
Abstract
Conus snails produce venoms containing numerous peptides such as the α-conotoxins (α-CTXs), which are well-known nicotinic acetylcholine receptor (nAChR) antagonists. Thirty-eight chromatographic fractions from Conus princeps venom extract were isolated by RP-HPLC. The biological activities of 37 fractions (0.07 µg/µL) were assayed by [...] Read more.
Conus snails produce venoms containing numerous peptides such as the α-conotoxins (α-CTXs), which are well-known nicotinic acetylcholine receptor (nAChR) antagonists. Thirty-eight chromatographic fractions from Conus princeps venom extract were isolated by RP-HPLC. The biological activities of 37 fractions (0.07 µg/µL) were assayed by two-electrode voltage clamp on human α7 nAChRs expressed in Xenopus laevis oocytes. Fractions F7 and F16 notably inhibited the response elicited by acetylcholine by 52.7 ± 15.2% and 59.6 ± 2.5%, respectively. Fraction F7 was purified, and an active peptide (F7-3) was isolated. Using a combination of Edman degradation, mass spectrometry, and RNASeq, we determined the sequence of peptide F7-3: AVKKTCIRSTOGSNWGRCCLTKMCHTLCCARSDCTCVYRSGKGHGCSCTS, with one hydroxyproline (O) and a free C-terminus. The average mass of this peptide, 10,735.54 Da, indicates that it is a homodimer of identical subunits, with 10 disulfide bonds in total. This peptide is clearly similar to αD-CTXs from species of the Indo-Pacific. Therefore, we called it αD-PiXXA. This toxin slowly and reversibly inhibited the ACh-induced response of the hα7 nAChR subtype, with an IC50 of 6.2 μM, and it does not affect the hα3β2 subtype at 6.5 μM. Full article
Show Figures

Figure 1

16 pages, 898 KiB  
Article
Effects of Predator-Prey Interactions on Predator Traits: Differentiation of Diets and Venoms of a Marine Snail
by David A. Weese and Thomas F. Duda, Jr.
Toxins 2019, 11(5), 299; https://doi.org/10.3390/toxins11050299 - 25 May 2019
Cited by 10 | Viewed by 3953
Abstract
Species interactions are fundamental ecological forces that can have significant impacts on the evolutionary trajectories of species. Nonetheless, the contribution of predator-prey interactions to genetic and phenotypic divergence remains largely unknown. Predatory marine snails of the family Conidae exhibit specializations for different prey [...] Read more.
Species interactions are fundamental ecological forces that can have significant impacts on the evolutionary trajectories of species. Nonetheless, the contribution of predator-prey interactions to genetic and phenotypic divergence remains largely unknown. Predatory marine snails of the family Conidae exhibit specializations for different prey items and intraspecific variation in prey utilization patterns at geographic scales. Because cone snails utilize venom to capture prey and venom peptides are direct gene products, it is feasible to examine the evolution of genes associated with changes in resource utilization. Here, we compared feeding ecologies and venom duct transcriptomes of individuals from three populations of Conus miliaris, a species that exhibits geographic variation in prey utilization and dietary breadth, in order to determine the extent to which dietary differences are correlated with differences in venom composition, and if expanded niche breadth is associated with increased variation in venom composition. While populations showed little to no overlap in resource utilization, taxonomic richness of prey was greatest at Easter Island. Changes in dietary breadth were associated with differences in expression patterns and increased genetic differentiation of toxin-related genes. The Easter Island population also exhibited greater diversity of toxin-related transcripts, but did not show increased variance in expression of these transcripts. These results imply that differences in dietary breadth contribute more to the structural and regulatory differentiation of venoms than differences in diet. Full article
Show Figures

Figure 1

13 pages, 1782 KiB  
Article
The Diversified O-Superfamily in Californiconus californicus Presents a Conotoxin with Antimycobacterial Activity
by Johanna Bernáldez-Sarabia, Andrea Figueroa-Montiel, Salvador Dueñas, Karla Cervantes-Luévano, Jesús A. Beltrán, Ernesto Ortiz, Samanta Jiménez, Lourival D. Possani, Jorge F. Paniagua-Solís, Jorge Gonzalez-Canudas and Alexei Licea-Navarro
Toxins 2019, 11(2), 128; https://doi.org/10.3390/toxins11020128 - 20 Feb 2019
Cited by 11 | Viewed by 3970
Abstract
Californiconus californicus, previously named Conus californicus, has always been considered a unique species within cone snails, because of its molecular, toxicological and morphological singularities; including the wide range of its diet, since it is capable of preying indifferently on fish, snails, [...] Read more.
Californiconus californicus, previously named Conus californicus, has always been considered a unique species within cone snails, because of its molecular, toxicological and morphological singularities; including the wide range of its diet, since it is capable of preying indifferently on fish, snails, octopus, shrimps, and worms. We report here a new cysteine pattern conotoxin assigned to the O1-superfamily capable of inhibiting the growth of Mycobacterium tuberculosis (Mtb). The conotoxin was tested on a pathogen reference strain (H37Rv) and multidrug-resistant strains, having an inhibition effect on growth with a minimal inhibitory concentration (MIC) range of 3.52–0.22 μM, similar concentrations to drugs used in clinics. The peptide was purified from the venom using reverse phase high-performance liquid chromatography (RP-HPLC), a partial sequence was constructed by Edman degradation, completed by RACE and confirmed with venom gland transcriptome. The 32-mer peptide containing eight cysteine residues was named O1_cal29b, according to the current nomenclature for this type of molecule. Moreover, transcriptomic analysis of O-superfamily toxins present in the venom gland of the snail allowed us to assign several signal peptides to O2 and O3 superfamilies not described before in C. californicus, with new conotoxins frameworks. Full article
Show Figures

Figure 1

Review

Jump to: Research

9 pages, 867 KiB  
Review
Conus Envenomation of Humans: In Fact and Fiction
by Alan J. Kohn
Toxins 2019, 11(1), 10; https://doi.org/10.3390/toxins11010010 - 27 Dec 2018
Cited by 17 | Viewed by 4229
Abstract
Prominent hallmarks of the widely distributed, mainly tropical marine snail genus Conus are: (1) its unusually high species diversity; it is the largest genus of animals in the sea, with more than 800 recognized species; and (2) its specialized feeding behavior of overcoming [...] Read more.
Prominent hallmarks of the widely distributed, mainly tropical marine snail genus Conus are: (1) its unusually high species diversity; it is the largest genus of animals in the sea, with more than 800 recognized species; and (2) its specialized feeding behavior of overcoming prey by injection with potent neurotoxic, paralytic venoms, and swallowing the victim whole. Including the first report of a human fatality from a Conus sting nearly 350 years ago, at least 141 human envenomations have been recorded, of which 36 were fatal. Most Conus species are quite specialized predators that can be classified in one of three major feeding guilds: they prey exclusively or nearly so on worms, primarily polychaete annelids, other gastropods, sometimes including other Conus species, or fishes. These differences are shown to relate to the severity of human envenomations, with the danger increasing generally in the order listed above and a strong likelihood that all of the known human fatalities may be attributable solely to the single piscivorous species C. geographus. Full article
Show Figures

Figure 1

Back to TopTop