Next Article in Journal
Chitosan Oleate Salt as an Amphiphilic Polymer for the Surface Modification of Poly-Lactic-Glycolic Acid (PLGA) Nanoparticles. Preliminary Studies of Mucoadhesion and Cell Interaction Properties
Previous Article in Journal
Anticoagulant Properties of a Green Algal Rhamnan-type Sulfated Polysaccharide and Its Low-molecular-weight Fragments Prepared by Mild Acid Degradation
Previous Article in Special Issue
APS8 Delays Tumor Growth in Mice by Inducing Apoptosis of Lung Adenocarcinoma Cells Expressing High Number of α7 Nicotinic Receptors
Article Menu
Issue 11 (November) cover image

Export Article

Open AccessArticle
Mar. Drugs 2018, 16(11), 446; https://doi.org/10.3390/md16110446

Identification of Novel Gymnodimines and Spirolides from the Marine Dinoflagellate Alexandrium ostenfeldii

1
Marine Chemistry, University of Bremen, Leobener Straße 6, 28359 Bremen, Germany
2
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Section Ecological Chemistry, Am Handelshafen 12, 27570 Bremerhaven, Germany
*
Authors to whom correspondence should be addressed.
Received: 13 September 2018 / Revised: 26 October 2018 / Accepted: 5 November 2018 / Published: 14 November 2018
(This article belongs to the Special Issue Marine Toxins Affecting Cholinergic System)
Full-Text   |   PDF [3942 KB, uploaded 14 November 2018]   |  

Abstract

Cyclic imine toxins are neurotoxic, macrocyclic compounds produced by marine dinoflagellates. Mass spectrometric screenings of extracts from natural plankton assemblages revealed a high chemical diversity among this toxin class, yet only few toxins are structurally known. Here we report the structural characterization of four novel cyclic-imine toxins (two gymnodimines (GYMs) and two spirolides (SPXs)) from cultures of Alexandrium ostenfeldii. A GYM with m/z 510 (1) was identified as 16-desmethylGYM D. A GYM with m/z 526 was identified as the hydroxylated degradation product of (1) with an exocyclic methylene at C-17 and an allylic hydroxyl group at C-18. This compound was named GYM E (2). We further identified a SPX with m/z 694 as 20-hydroxy-13,19-didesmethylSPX C (10) and a SPX with m/z 696 as 20-hydroxy-13,19-didesmethylSPX D (11). This is the first report of GYMs without a methyl group at ring D and SPXs with hydroxyl groups at position C-20. These compounds can be conceived as derivatives of the same nascent polyketide chain, supporting the hypothesis that GYMs and SPXs are produced through common biosynthetic genes. Both novel GYMs 1 and 2 were detected in significant amounts in extracts from natural plankton assemblages (1: 447 pg; 2: 1250 pg; 11: 40 pg per mL filtered seawater respectively). View Full-Text
Keywords: gymnodimine; spirolide; structure elucidation; neuro-toxin; Alexandrium ostenfeldii; harmful algal boom (HAB) gymnodimine; spirolide; structure elucidation; neuro-toxin; Alexandrium ostenfeldii; harmful algal boom (HAB)
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Supplementary materials

  • Supplementary File 1:

    PDF-Document (PDF, 11656 KB)

  • Externally hosted supplementary file 1
    Link: https://doi.pangaea.de/10.1594/PANGAEA.895116
    Description: The following are available online at www.mdpi.com/xxx/s1, Figure S1: Structures of known and novel gymnodimines; Figure S2: Structures of known and novel spirolides; Figure S4-S22 NMR-spectra of 1; Figure S23: CD-spectra of 1 and 4 and simulated CD spectra of 1, S24-S31 NMR-spectra of 2; Figure S32-S53 NMR-spectra of 10; Figure S54-S62 NMR-spectra of 11; Table S1: Mass transitions of spiroimines included in LC-MS/MS analysis; Figure S63: LC-MS/MS chromatogram of station SL92-2. Raw NMR data (Topspin) and annotated Mestre files are available in the data repository PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.895116 .
SciFeed

Share & Cite This Article

MDPI and ACS Style

Zurhelle, C.; Nieva, J.; Tillmann, U.; Harder, T.; Krock, B.; Tebben, J. Identification of Novel Gymnodimines and Spirolides from the Marine Dinoflagellate Alexandrium ostenfeldii. Mar. Drugs 2018, 16, 446.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Mar. Drugs EISSN 1660-3397 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top