Premium
Brevetoxin, the Dinoflagellate Neurotoxin, Localizes to Thylakoid Membranes and Interacts with the Light‐Harvesting Complex II (LHCII) of Photosystem II
Author(s) -
Cassell Ryan T.,
Chen Wei,
Thomas Serge,
Liu Li,
Rein Kathleen S.
Publication year - 2015
Publication title -
chembiochem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.05
H-Index - 126
eISSN - 1439-7633
pISSN - 1439-4227
DOI - 10.1002/cbic.201402669
Subject(s) - dinoflagellate , thylakoid , photosystem ii , biology , reactive oxygen species , biophysics , chloroplast , marine toxin , biochemistry , neurotoxin , non photochemical quenching , photosynthesis , chemistry , toxin , botany , gene
The brevetoxins are neurotoxins that are produced by the “Florida red tide” dinoflagellate Karenia brevis. They bind to and activate the voltage‐gated sodium channels in higher organisms, specifically the Na v 1.4 and Na v 1.5 channel subtypes. However, the native physiological function that the brevetoxins perform for K. brevis is unknown. By using fluorescent and photoactivatable derivatives, brevetoxin was shown to localize to the chloroplast of K. brevis where it binds to the light‐harvesting complex II (LHCII) and thioredoxin. The LHCII is essential to non‐photochemical quenching (NPQ), whereas thioredoxins are critical to the maintenance of redox homeostasis within the chloroplast and contribute to the scavenging of reactive oxygen. A culture of K. brevis producing low levels of toxin was shown to be deficient in NPQ and produced reactive oxygen species at twice the rate of the toxic culture, implicating a role in NPQ for the brevetoxins.