Nodularia is a genus of filamentous

Filamentation

Filamentation is the anomalous growth of certain bacteria, such as E. coli, in which cells continue to elongate but do not divide . Bacterial filamentation is often observed as a result of bacteria responding to various stresses, including DNA damage or inhibition of replication...

 nitrogen-fixing cyanobacteria, or blue-green algae. They occur mainly in brackish or salinic waters, such as the hypersaline

Hypersaline lake

A hypersaline lake is a landlocked body of water that contains significant concentrations of sodium chloride or other mineral salts, with saline levels surpassing that of ocean water . Specific microbial and crustacean species thrive in these high salinity environments that are otherwise...

 Makgadikgadi Pans, the Peel-Harvey Estuary in Western Australia or the Baltic Sea

Baltic Sea

The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...

. Nodularia cells occasionally form heavy algal bloom

Algal bloom

An algal bloom is a rapid increase or accumulation in the population of algae in an aquatic system. Algal blooms may occur in freshwater as well as marine environments. Typically, only one or a small number of phytoplankton species are involved, and some blooms may be recognized by discoloration...

s. Some strains produce a cyanotoxin

Cyanotoxin

Cyanotoxins are toxins produced by bacteria called cyanobacteria . Cyanobacteria are found almost everywhere, but particularly in lakes and in the ocean where, under certain conditions, they reproduce exponentially to form blooms. Blooming cyanobacteria can produce cyanotoxins in such...

 called nodularin R, which is harmful to humans.

Morphology

Nodularia is forms solitary filaments or groups of filaments. They reproduce by the formation of hormogonia, filament breakage, and by akinetes .

See also

Kruger, T., Oelmuller, R., and Luckas, B. (2009) Comparative PCR analysis of toxic Nodularia spumigena and non-toxic Nodularia harveyana (Nostocales, Cyanobacteria) with respect to the nodularia synthetase gene cluster. Eur. J. Phycol. 44 (3): 291 - 295.