RT Journal Article
T1 Structure elucidation and biological evaluation of Maitotoxin-3, a Homologue of Gambierone, from Gambierdiscus belizeanus
A1 Boente Juncal, Andrea
A1 Álvarez, Mercedes
A1 Antelo Queijo, Álvaro
A1 Rodríguez Filgueiras, Inés
A1 Calabro, Kevin
A1 Vale González, María del Carmen
A1 Thomas, Olivier P.
A1 Botana López, Luis Miguel
K1 44-methylgambierone
K1 Gambierone
K1 Maitotoxin
K1 Gambierdiscus belizeanus
K1 Cytosolic calcium concentration
K1 Glutamate receptors
K1 Neurotoxicity
K1 Ciguatera
K1 Maitotoxin-3
AB Gambierdiscus species are the producers of the marine toxins ciguatoxins and maitotoxins which cause worldwide human intoxications recognized as Ciguatera Fish Poisoning. A deep chemical investigation of a cultured strain of G. belizeanus, collected in the Caribbean Sea, led to the identification of a structural homologue of the recently described gambierone isolated from the same strain. The structure was elucidated mainly by comparison of NMR and MS data with those of gambierone and ascertained by 2D NMR data analyses. Gratifyingly, a close inspection of the MS data of the new 44-methylgambierone suggests that this toxin would actually correspond to the structure of maitotoxin-3 (MTX3, m/z 1039.4957 for the protonated adduct) detected in 1994 in a Pacific strain of Gambierdiscus and recently shown in routine monitoring programs. Therefore, this work provides for the first time the chemical identification of the MTX3 molecule by NMR. Furthermore, biological data confirmed the similar activities of both gambierone and 44-methylgambierone. Both gambierone and MTX3 induced a small increase in the cytosolic calcium concentration but only MTX3 caused cell cytotoxicity at micromolar concentrations. Moreover, chronic exposure of human cortical neurons to either gambierone or MTX3 altered the expression of ionotropic glutamate receptors, an effect already described before for the synthetic ciguatoxin CTX3C. However, even when gambierone and MTX3 affected glutamate receptor expression in a similar manner their effect on receptor expression differed from that of CTX3C, since both toxins decreased AMPA receptor levels while increasing N-methyl-d-aspartate (NMDA) receptor protein. Thus, further studies should be pursued to clarify the similarities and differences in the biological activity between the known ciguatoxins and the new identified molecule as well as its contribution to the neurological symptoms of ciguatera
PB MDPI
YR 2019
FD 2019
LK http://hdl.handle.net/10347/21060
UL http://hdl.handle.net/10347/21060
LA eng
NO Boente-Juncal, A.; Álvarez, M.; Antelo, Á.; Rodríguez, I.; Calabro, K.; Vale, C.; Thomas, O.P.; Botana, L.M. Structure Elucidation and Biological Evaluation of Maitotoxin-3, a Homologue of Gambierone, from Gambierdiscus belizeanus. Toxins 2019, 11, 79
NO Andrea Boente-Juncal is recipient of a fellowship from Ministerio de Educación, Cultura y Deporte,Spain. The research leading to these results has received funding from the following FEDER cofunded-grants.From Conselleria de Cultura, Educacion e Ordenación Universitaria, Xunta de Galicia, 2017 GRC GI-1682 (ED431C2017/01). From CDTI and Technological Funds, supported by Ministerio de Economía, Industria y Competitividad,AGL2014-58210-R, AGL2016-78728-R (AEI/FEDER, UE), ISCIII/PI16/01830 and RTC-2016-5507-2, ITC-20161072.From European Union POCTEP 0161-Nanoeaters -1-E-1, Interreg AlertoxNet EAPA-317-2016, Interreg AgritoxEAPA-998-2018, and H2020 778069-EMERTOX
DS Minerva
RD 28 abr 2026