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Anabaena is a genus of filamentous cyanobacteria that exist as plankton. They are known for nitrogen-fixing abilities, and they form symbiotic relationships with certain plants, such as the mosquito fern. They are one of four genera of cyanobacteria that produce neurotoxins, which are
Cyanobacteria cultured in specific media: Cyanobacteria can be helpful in agriculture as they have the ability to fix atmospheric nitrogen in soil. The unicellular cyanobacterium Synechocystis sp. PCC6803 was the third prokaryote and first photosynthetic organism whose genome was completely sequenced . [ 242 ]
Cyanobacteria are found almost everywhere, but particularly in lakes and in the ocean where, under high concentration of phosphorus conditions, they reproduce exponentially to form blooms. Blooming cyanobacteria can produce cyanotoxins in such concentrations that they can poison and even kill animals and humans.
[41] [42] It is a cyanotoxin produced by at least four different genera of cyanobacteria, and has been reported in North America, Europe, Africa, Asia, and New Zealand. [ 75 ] Toxic effects from anatoxin- a progress very rapidly because it acts directly on the nerve cells ( neurons ).
Cyanobacteria are also photosynthetically active and can therefore meet carbon requirements independently. [7] In symbioses involving cyanobacteria, at least one of the partners must be photoautotrophic in order to generate sufficient amounts of carbon for the mutualistic system. [ 2 ]
Cyanobacteria usually obtain a fixed carbon (carbohydrate) by photosynthesis. The lack of water-splitting in photosystem II prevents heterocysts from performing photosynthesis, so the vegetative cells provide them with carbohydrates, which is thought to be sucrose. The fixed carbon and nitrogen sources are exchanged through channels between the ...
Because they can form large surface blooms, they are thought to be able to outcompete other phytoplankton by monopolizing light in the photic zone. [ citation needed ] Microcystis spp. are also capable of efficient uptake of phosphate and nitrogen; they are believed to be strongly influenced by nitrogen to phosphorus ratios ( N:P ratio ). [ 4 ]
Cyanobacteria prefer to live in water bodies such as lake, ponds, reservoirs, and slow-moving streams. When the water is warm there are enough nutrients available for the bacteria to survive. Most cyanobacteria produce toxins, of which microcystin is only one group.