Cyanobacteria, which includes blue-green algae, are a kind of bacteria. Cyanobacteria are equipped to use the sun’s energy to make their own food in their aquatic habitat via photosynthesis. The colour, which was a by-product of the bacteria’s photosynthetic activity, and their appearance as an algal-like scum on pond surfaces gave rise to the moniker “blue-green algae.” They were mistaken for algae until their actual identity as bacteria was established.
Despite the fact that the bacterial nature of the microorganism was just recently discovered, cyanobacteria have been there for a long time. Cyanobacteria fossils dating back 3.5 billion years have been unearthed, making them the oldest remains of any life known so far on Earth.
A Short Guide on Blue Green Algae
Now we will learn more about what do we mean by blue green algae, effects on living organisms,
group it belongs to and finally, we will look at the examples of blue green algae.
Blue green algae
Any of a broad, varied group of prokaryotic, mostly photosynthetic organisms known as blue-green algae or cyanobacteria. In many aspects, cyanobacteria resemble eukaryotic algae, including physical traits and ecological niches, and were formerly considered as algae, thus the popular term blue-green algae. Algae have now been reclassified as protists, and the blue-green algae have been grouped alongside bacteria in the prokaryotic kingdom Monera due to their prokaryotic nature.
Cyanobacteria lack a membrane-bound nucleus, mitochondria, Golgi apparatus, chloroplasts, and endoplasmic reticulum, much like all other prokaryotes. In prokaryotes, the bacterial cell membrane performs all of the activities that these membrane-bound organelles do in eukaryotes.
Some cyanobacteria, particularly planktonic species, feature gas vesicles that help them stay afloat. To further identify the group within the kingdom, chemical, genetic, and physiological traits are employed. Cyanobacteria may be filamentous or unicellular. Sheaths are used to link additional cells or filaments together to form colonies.
Effects on living organisms-
All blue-green algae generate beta-methylamino-l-alanine, a simple amino acid that has been found to cause alterations in monkey brain structure that are comparable to those seen in Alzheimer’s disease patients. As a result, extended exposure to blue-green algae and hence BMAA may raise the risk of neuron illnesses in humans, although this has yet to be demonstrated.
Blue-green algal blooms may have negative environmental consequences in addition to their impacts on people and domestic animals. Pansteatitis, often known as ‘yellow fat sickness,’ has claimed the lives of a large number of crocodiles in Africa. It’s been speculated that the crocodiles got the sickness by eating fish that had perished from it.
Group it belongs to-
Blue-green algae, also known as Cyanobacteria, is a wide group of prokaryotic organisms that share physical and ecological traits with eukaryotic algae and were formerly considered as algae, thus the popular name. Because blue-green algae are prokaryotic, they are classified as part of the Monera kingdom of prokaryotes.
Prokaryotes- A prokaryote is an organism that lacks a defined nucleus and other organelles owing to the absence of internal membranes or other factors. These creatures lack a cell nucleus as well as any other membrane-bound organelles. The majority of prokaryotes are unicellular, although others are multicellular.
Bacteria are a sort of prokaryotic critter that is well-known. Because they lack internal membranes, prokaryotes differ from eukaryotes. The bacterial cell membrane, which acts as the cell’s primary osmotic barrier, is made up of phospholipids. The cytoplasm contains ribosomes, which carry out protein synthesis, and a double-stranded deoxyribonucleic acid (DNA) chromosome, which is generally circular.
Many prokaryotes have plasmids, which are circular DNA units with extracellular functions such as expressing proteins that inactivate antibiotics. Flagella are seen on several prokaryotes. In terms of design and movement, prokaryotes’ flagella vary from those of eukaryotes. Also see eukaryote and bacterium.
Examples of blue green algae-
Nostoc, Oscillatoria, Microcystis etc are some examples.
1.Nostoc- A genus of blue-green algae having beadlike strands of cells that are clumped together in a gelatinous mass. Nostoc masses range in size from microscopic to walnut-sized and may be found on soil and floating in still water. Fragmentation is a type of method used for reproduction. A unique thick-walled cell (akinete) has the capacity to resist lengthy durations of desiccation.
When the akinete of one species is wet after 70 years of dry storage, it germinates into a filament. Nostoc includes two pigments, blue phycocyanin and red phycoerythrin, as well as chlorophyll, and can fix nitrogen in specialised cells called heterocysts, like most blue-green algae. In Asia, a terrestrial species has been utilised as a supplement to diet.
2.Oscillatoria- A blue-green algae genus found in freshwater habitats such as hot springs. The slow, rhythmic oscillating motion of this unbranched filamentous alga, which may be seen individually or in tangled mats, is considered to be caused by mucilage secretion that pulls the filament away from the direction of excretion. Fragmentation is a method of reproduction in which dead concave cells (separation disks) divide the filament into parts (hormogonia). The mucilage sheath is quite thin when it is present.
3.Microcystis aeruginosa– It is a single-celled blue-green alga (cyanobacterium) found in surface waters. Dolichospermum (formerly Anabaena), Fischerella, Gloeotrichia, Nodularia, Nostoc, Oscillatoria, Microcystis, and Planktothrix all generate microcystins. Microcystins are the most frequent cyanobacterial toxins, and they may bioaccumulate in fish, mussels, and zooplankton, among other aquatic vertebrates and invertebrates. Microcystins are predominantly a hepatotoxin that affects the liver, but they may also harm the kidneys and reproductive system.
Conclusion-
In this article we read about blue green algae, effects on living organisms, groups it belongs to and read examples of blue green algae and brief details on them. Cyanobacteria, or blue-green algae, are found in all natural waterways and play a crucial part in the natural cycling of nutrients in the environment and food chain. Blue-green algae is used to treat high blood pressure and as a protein supplement by people. It’s also used to treat excessive blood cholesterol or other fats (lipids), diabetes, obesity, and a variety of other ailments.