- singular of cyanobacteria.
cyanobacterium
Americannoun
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Any of a phylum of photosynthetic bacteria that live in water or damp soil and were once thought to be plants. Cyanobacteria have chlorophyll as well as carotenoid and phycobilin pigments, and they conduct photosynthesis in membranes known as thylakoids (which are also found in plant chloroplasts). Cyanobacteria may exist as individual cells or as filaments, and some species live in colonies. Many species secrete a mucilaginous substance that binds the cells or filaments together in colored (often bluish-green) masses. Cyanobacteria exist today in some 7,500 species, many of which are symbiotes, and have lived on Earth for 2.7 billion years. Since all species produce oxygen as a byproduct of metabolism, it is thought that much of Earth's atmospheric oxygen can be attributed to cyanobacteria. Many species can also fix nitrogen and so play an important role in the nitrogen cycle.
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Also called blue-green alga
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Significantly, the study also found evidence suggesting that far-red light photosynthesis can be gained by a cyanobacterium through horizontal gene transfer.
From Science Daily ● Nov. 28, 2023
In addition, the bloom-forming cyanobacterium has genes that enable it to store nitrogen, a key nutrient, which may provide another competitive advantage over the many lake microbes that did not.
From Science Magazine ● Jul. 5, 2022
The two are forever on the trail of these composite symbiotic organisms, which they describe in the book as “an intensive cooperation between a fungus and an alga or a cyanobacterium, and sometimes all three.”
From Seattle Times ● Nov. 22, 2021
Some 2 billion years ago, a single-celled organism in Earth’s primeval ocean engulfed a mitochondrion and a cyanobacterium — and, now able to generate energy and photosynthesize, shunted off to change the world.
From Nature ● Apr. 2, 2019
Lichens are a symbiotic relationship between a fungus and a photosynthetic organism, usually an alga or cyanobacterium.
From Textbooks ● Apr. 25, 2013
Multicellular cyanobacteria evolved gradually from single-celled ancestors, gaining complexity over time.
From Science Daily ● Apr. 20, 2026
Even today, cyanobacteria remain essential to life on Earth.
From Science Daily ● Apr. 20, 2026
Organisms living near cyanobacteria could have used this enzyme to rapidly consume small amounts of oxygen as it was produced.
From Science Daily ● Feb. 18, 2026
Previous studies helped establish that cyanobacteria began producing oxygen around 2.9 billion years ago, while oxygen did not permanently accumulate in the atmosphere until roughly 2.33 billion years ago during the Great Oxidation Event.
From Science Daily ● Feb. 18, 2026
The beauty of the sky contrasts sharply with the water, sometimes blue, but often a murky green from cyanobacteria or stained black.
From BBC ● Jan. 29, 2026
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
