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Pbtx-2 Research Paper

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PbTx-1 and PbTx-2 are the parent algal toxins from which others are derived. PbTx-2 (Figure1) is the most abundant brevetoxin produced by K. brevis, and PbTx-1 (Figure2) is the most potent. Currently, there are more than 10 brevetoxins have been identified in Karenia brevis blooms, including products of reduction, oxidation, and hydrolysis. These molecules are made up of a single carbon chain locked into a ladder-like structure. Cyclic ethers of sizes ranging from five- to nine-membered rings all fuse in a trans/syn/trans style is remarkable regularity feature. Both A and B type toxins possess a lactone functionality in the A-ring, have a strictly rigid region in the terminal four rings, possess a side chain allowing modest modification at …show more content…

They are classified according to the trigger that opens the channel for such ions, either a voltage change or a binding of a substance to the ligand-gated sodium channels. Sodium channels consist of a large α subunit that associates with other proteins, such as β subunits. An α subunit forms the core of the channel and is functional on its own. When the α subunit protein is expressed by a cell, it is able to form channels that conduct Na+ in a voltage-gated way, even if β subunits or other known modulating proteins are not expressed. When accessory proteins assemble with α subunits, the resulting complex can display altered voltage dependence and cellular localization. Binding of natural brevetoxins to voltage-sensitive sodium channels (VSSC) results in a cadre of four distinct effects: a shifting of the activation potential to more negative values; prolonged channel open times; inhibition of inactivation; and induction of subconductance states. Individual brevetoxins exhibit differential sodium channel binding affinities and potencies. Differences in affinity of the natural toxins have been attributed to variations in lipophilicity, topographic features relative to the binding site, and differential toxicities based on affinity governed by specific molecular or structural differences of each toxin. Regardless of affinity, all toxins affect …show more content…

The floc may then float to the top of the liquid, settle to the bottom, be readily filtered from the liquid. It is a way to removes fine K. brevis cells and toxins by binding with them and causing them to clump together. Clay flocculation can be considered as one of the control technologies with a partially successful track record in the marine environment. Clay flocculation has been used to protect aquaculture facilities from red tides in Asia. There are many natural substances can be used as flocculants, such as sand, shells, sediment. For the treatment of red tide, spray the area with clay slurry from a boat. As the slurry floats down through the water column it binds with the algae cells, clumps together and drifts down to the sea bottom. Ideally, the cells become trapped on the bottom and die. However, flocculation applications may be limited to small-scale treatments and its efficacy will vary with environmental

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