Oscillatoria | |
---|---|
Oscillatoria princeps | |
Scientific classification | |
Domain: | Bacteria |
Phylum: | Cyanobacteria |
Class: | Cyanophyceae |
Order: | Oscillatoriales |
Family: | Oscillatoriaceae |
Genus: | Oscillatoria Vaucher ex Gomont, 1822 |
Type species | |
Oscillatoria princeps Vaucher ex Gomont | |
Species | |
See list in body text |
Oscillatoria is a genus of filamentous cyanobacteria. It is often found in freshwater environments. [1] Its name refers to the oscillating motion of its filaments as they slide against each other to position the colony to face a light source. [2] Oscillatoria uses photosynthesis to survive and reproduce. Each filament of Oscillatoria consists of a row of cells called a trichome. The tip of the trichome oscillates like a pendulum.
Reproduction takes place asexually by fragmentation. Usually the filament breaks into a number of fragments called hormogonia. Each hormogonium consist of one or more cells and grows into a filament by cell division in one direction. [1]
As a result of recent genetic analyses, several new genera were erected from this genus, e.g. Tenebriella . [3]
Oscillatoria are the subject of research into the natural production of butylated hydroxytoluene (BHT), [4] an antioxidant, food additive, and industrial chemical.
Cyclic peptides called venturamides, which may have anti-malarial activity, have been isolated from bacteria in this genus. They are the first peptides with this activity to have been found in cyanobacteria. [5]
Serinolamide A is a cannabinoid structurally related to Anandamide that has been found to occur in Oscillatoria species. [6]
Oscillatoria contains the following species: [7]
Lyngbya is a genus of cyanobacteria, unicellular autotrophs that form the basis of the oceanic food chain.
Spirogyra is a genus of filamentous charophyte green algae of the order Zygnematales, named for the helical or spiral arrangement of the chloroplasts that is characteristic of the genus. Spirogyra species, of which there are more than 400, are commonly found in freshwater habitats. Spirogyra measures approximately 10 to 100 micrometres in width and may grow to several centimetres in length. It is often observed as green slimy patches on the ground near ponds and other water bodies having stagnant water.
Nostoc, also known as star jelly, troll's butter, spit of moon, fallen star, witch's butter, and witch's jelly, is the most common genus of cyanobacteria found in a variety of both aquatic and terrestrial environments that may form colonies composed of filaments of moniliform cells in a gelatinous sheath of polysaccharides. It may also grow symbiotically within the tissues of plants, providing nitrogen to its host through the action of terminally differentiated cells known as heterocysts. Nostoc is a genus that includes many species that are diverse in morphology, habitat distribution, and ecological function. Nostoc can be found in soil, on moist rocks, at the bottom of lakes and springs, and rarely in marine habitats. It may also be found in terrestrial temperate, desert, tropical, or polar environments.
Moorea producens is a species of filamentous cyanobacteria in the genus Moorea, including tropical marine strains formerly classified as Lyngbya majuscula due to morphological resemblance but separated based on genetic evidence. Moorea producens grows on seagrass and is one of the causes of the human skin irritation seaweed dermatitis. It is known as fireweed in Australia and stinging limu in Hawaii.
The Rivulariaceae are a family of cyanobacteria within the Nostocales in which the filaments (trichomes) are tapered from wider at the base to narrower at the tip.
Vaucheria is a genus of Xanthophyceae or yellow-green algae known as water felt. It is one of only two genera in the family Vaucheriaceae. The type species of the genus is Vaucheria disperma.
Scytonema is a genus of photosynthetic cyanobacteria that contains over 100 species. It grows in filaments that form dark mats. Many species are aquatic and are either free-floating or grow attached to a submerged substrate, while others species grow on terrestrial rocks, wood, soil, or plants. Scytonema is a nitrogen fixer, and can provide fixed nitrogen to the leaves of plants on which it is growing. Some species of Scytonema form a symbiotic relationship with fungi to produce a lichen.
Bangia is an extant genus of division Rhodophyta that grows in marine or freshwater habitats. Bangia has small thalli with rapid growth and high reproductive output, and exhibits behavior characteristic of r-selected species. The plants are attached by down-growing rhizoids, usually in dense purple-black to rust-colored clumps. The chloroplasts of Bangia, like others in the division Rhodophyta, contain chlorophyll a and sometimes chlorophyll d, as well as accessory pigments such as phycobilin pigments and xanthophylls. Depending on the relative proportions of these pigments and the light conditions, the overall color of the plant can range from green to red to purple to grey; however, the red pigment, phycoerythrin, is usually dominant.
Planktothrix is a diverse genus of filamentous cyanobacteria observed to amass in algal blooms in water ecosystems across the globe. Like all Oscillatoriales, Planktothrix species have no heterocysts and no akinetes. Planktothrix are unique because they have trichomes and contain gas vacuoles unlike typical planktonic organisms. Previously, some species of the taxon were grouped within the genus Oscillatoria, but recent work has defined Planktothrix as its own genus. A tremendous body of work on Planktothrix ecology and physiology has been done by Anthony E. Walsby, and the 55.6 kb microcystin synthetase gene which gives these organisms the ability to synthesize toxins has been sequenced. P. agardhii is an example of a type species of the genus. P. agardhii and P. rubescens are commonly observed in lakes of the Northern Hemisphere where they are known producers of potent hepatotoxins called microcystins.
Raphidiopsis raciborskii is a freshwater cyanobacterium.
Lyngbya majuscula is a species of filamentous cyanobacteria in the genus Lyngbya. It is named after the Dane Hans Christian Lyngbye.
Laurencia is a genus of red algae that grow in temperate and tropical shore areas, in littoral to sublittoral habitats, at depths up to 65 m (213 ft).
Rivularia is a genus of cyanobacteria of the family Rivulariaceae.
Oscillatoria princeps is the type species (lectotype) of the cyanobacterial genus Oscillatoria.
Trichodesmium thiebautii is a cyanobacteria that is often found in open oceans of tropical and subtropical regions and is known to be a contributor to large oceanic surface blooms. This microbial species is a diazotroph, meaning it fixes nitrogen gas (N2), but it does so without the use of heterocysts. T. thiebautii is able to simultaneously perform oxygenic photosynthesis. T. thiebautii was discovered in 1892 by M.A. Gomont. T. thiebautii are important for nutrient cycling in marine habitats because of their ability to fix N2, a limiting nutrient in ocean ecosystems.
Oscillatoria brevis is a species of the genus Oscillatoria first identified in 1892. It is a blue-green filamentous cyanobacterium, which can be found in brackish and fresh waterways. O. brevis can also be isolated from soil.
Kamptonema is a genus of cyanobacteria belonging to the family Microcoleaceae.
Jaaginema is a genus of cyanobacteria belonging to the family Pseudanabaenaceae.
Callithamnion is a genus of algae belonging to the family Callithamniaceae.