Research
The Toxins of Cyanobacteria-"CYANOTOXINS"
Pond
In Beijing
The world-wide occurrence of toxic cyano location in fresh and brackish
waters creates problems for all life forms. Our laboratory has assisted
in establishing programs to study cyanobacterial related water problems
in Europe, Asia, Africa, North and South American. Research topics include
occurrence and distribution of toxic cyanobacteria to the genetics of toxin
regulation.
Pond In Beijing has been contaminated by an overgrowth, or waterbloom,
of toxic cyanobacteria(green scum). These bacteria, flourishing in the
Grandview Garden Park, are members of the wide spread genus Microcystis,
many species of which produce potent liver toxins. The toxins have killed
animals, and the consumption of low doses in drinking water is suspected
of contributing to a high rate of human liver cancer in certain parts of
China.
Mass
Of Cyanobacteria
Most water based poisonings of cyanobacteria occur when heavy surface
growths or scums accumulate near shorelines of lakes, ponds and reservoirs
where animals have easy access to toxic levels of cells. Our lab is also
investigating occurrences of toxic cyanobacteria at levels which can cause
chronic and sub-chronic toxicities such as tumor promotion.
Close to the shore of Balgavies Loch, near dundee, Scotland, has
the typical appearance of a waterbloom seen at short range: it resembles
a thick pool of green oil paint. This bloom occurred in 1981 and was found
to consist of species in the genus Microcystis.
Microcystis 
Nodularia 
Anabaena
Toxins studied to date in
our laboratory belong to two groups defined by the symptoms they produce
in animals. Anabaena, Oscillatoria, Lyngbya, and Aphanizomenon produce
neurotoxic, anatoxins and/or saxitoxin.. Anatoxin is a potent nicotinic
agonist which mimics acetylcholine and is used as a research tool in neurobiology.
Anatoxin-a(s) is a structurally new organophosphate that inhibits acetylcholinesterase.
Certain cyanobacteria also produce Paralytic Shellfish Poisons - The saxitoxins.
Visiting Research Scientist Projects
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This page was created on April 30,1997
Send comments and suggestions to Thasarin
Khwaengospha, s002txk@desire.wright.edu