Pre_GI: SWBIT SVG BLASTN

Query: NC_007413:5742406 Anabaena variabilis ATCC 29413, complete genome

Lineage: Anabaena variabilis; Anabaena; Nostocaceae; Nostocales; Cyanobacteria; Bacteria

General Information: These cyanobacteria are bluegreen algae that are capable of fixing carbon and nitrogen. They form long filaments and can be found worldwide in various aquatic environments as well as some terrestrial ones. These bacteria can form a variety of differentiated cell types, including spore-like cells (akinetes), small motile filaments (hormongia) and most importantly, heterocysts that are nitrogen-producing cells. The heterocyst produces multiple layers outside of its cell wall, shuts down photosystem II in order to inhibit oxygenic photosynthesis and ramps up metabolism in order to use up the oxygen present. Heterocysts donate fixed nitrogen compounds as amino acids to neighboring cells and in return receive a photosynthetically produced carbon source such as sucrose. These organisms produce toxic blooms in aquatic environments that are harmful or fatal to animals and humans due to the various cyanotoxins they produce. Anabaena variabilis is a filamentous heterocyst-forming cyanobacterium that fixes nitrogen and CO2 using the energy of sunlight via oxygen-evolving plant-type photosynthesis. In addition, this organism has been studied extensively for the production of hydrogen using solar energy.

Subject: NC_008312:3793760 Trichodesmium erythraeum IMS101, complete genome

Lineage: Trichodesmium erythraeum; Trichodesmium; ; Oscillatoriales; Cyanobacteria; Bacteria

General Information: Trichodesmium erythraeum strain IMS101 was isolated from the North Carolina coast in 1992 and grows in straight filaments. Filamentous marine cyanobacterium. This filamentous marine cyanobacterium is a nitrogen-fixing organism that contribues a significant amount of the global fixed nitrogen each year. These bacteria are unusual in that nitrogen fixation takes place in a differentiated cell called the diazocyte which is different from the nitrogen-fixing differentiated cell (heterocyst) found in other cyanobacteria. The diazocyte is developed in order to protect the oxygen-sensitive nitrogenases and includes a number of changes including production of more membranes and down-regulation of photosynthetic activity during times of peak nitrogen fixation (noontime). This organism gives the Red Sea its name when large blooms appear and is one of the organisms most often associated with large blooms in marine waters.