title: The Bacterial (Vibrio alginolyticus) Production of Tetrodotoxin in the Ribbon Worm Lineus longissimus-Just a False Positive?
abstract: We test previous claims that the bacteria Vibrio alginolyticus produces tetrodotoxin (TTX) when living in symbiosis with the nemertean Lineus longissimus by a setup with bacteria cultivation for TTX production. Toxicity experiments on the shore crab, Carcinus maenas, demonstrated the presence of a paralytic toxin, but evidence from LC-MS and electrophysiological measurements of voltage-gated sodium channel-dependent nerve conductance in male Wistar rat tissue showed conclusively that this effect did not originate from TTX. However, a compound of similar molecular weight was found, albeit apparently non-toxic, and with different LC retention time and MS/MS fragmentation pattern than those of TTX. We conclude that C. maenas paralysis and death likely emanate from a compound <5 kDa, and via a different mechanism of action than that of TTX. The similarity in mass between TTX and the Vibrio-produced low-molecular-weight, non-toxic compound invokes that thorough analysis is required when assessing TTX production. Based on our findings, we suggest that re-examination of some published claims of TTX production may be warranted.
authors.affiliation: Swedish Species Information Centre, Swedish University of Agricultural Sciences, 75007 Uppsala, Sweden. malin.strand@slu.se.|Division of Pharmacognosy, Department of Medicinal Chemistry, Uppsala University, 75237 Uppsala, Sweden. malin.strand@slu.se.
authors.forename: Malin
authors.initials: M
authors.lastname: Strand
authors.affiliation: Division of Biotechnology, Lund University, 22100 Lund, Sweden. martin.hedstrom@biotek.lu.se.
authors.forename: Martin
authors.initials: M
authors.lastname: Hedström
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, 40530 Gothenburg, Sweden. henrik.seth@bioenv.gu.se.|Department of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, 40530 Gothenburg, Sweden. henrik.seth@bioenv.gu.se.
authors.forename: Henrik
authors.initials: H
authors.lastname: Seth
authors.affiliation: School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool L32AJ, UK. eric.mcevoy@sky.com.
authors.forename: Eric G
authors.initials: EG
authors.lastname: McEvoy
authors.affiliation: Division of Pharmacognosy, Department of Medicinal Chemistry, Uppsala University, 75237 Uppsala, Sweden. erik.jacobsson@fkog.uu.se.
authors.forename: Erik
authors.initials: E
authors.lastname: Jacobsson
authors.affiliation: Division of Pharmacognosy, Department of Medicinal Chemistry, Uppsala University, 75237 Uppsala, Sweden. ulf.goransson@fkog.uu.se.
authors.forename: Ulf
authors.initials: U
authors.lastname: Göransson
authors.affiliation: Linnaeus University Centre for Biomaterials Chemistry, Department of Chemistry and Biomedical Sciences, Linnaeus University, 39234 Kalmar, Sweden. hakan.andersson@lnu.se.
authors.forename: Håkan S
authors.initials: HS
authors.lastname: Andersson
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, 40530 Gothenburg, Sweden. per.sundberg@bioenv.gu.se.
authors.forename: Per
authors.initials: P
authors.lastname: Sundberg
mesh_terms: D000818:Animals; D003386:Brachyura / Q000382:microbiology / Q000469:parasitology; D002853:Chromatography, Liquid / Q000379:methods; D006376:Helminths / Q000382:microbiology*; D008297:Male; D008970:Molecular Weight; D010243:Paralysis / Q000139:chemically induced; D051381:Rats; D017208:Rats, Wistar; D013559:Symbiosis / Q000502:physiology; D053719:Tandem Mass Spectrometry / Q000379:methods; D013779:Tetrodotoxin / Q000633:toxicity*; D044149:Vibrio alginolyticus / Q000378:metabolism*; D061566:Voltage-Gated Sodium Channels / Q000378:metabolism
chemical_list: D061566:Voltage-Gated Sodium Channels; D013779:Tetrodotoxin
keywords: LC-MS; Vibrio; axonal conductance; mucus; nemertean; tetrodotoxin