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Photoautotrophic, oxygen-producing cyanobacteria created the conditions in the planet's early atmosphere that directed the evolution of aerobic metabolism and eukaryotic photosynthesis. Cyanobacteria fulfill vital ecological functions in the world's oceans, being important contributors to global carbon and nitrogen budgets."
Cyanobacteria are photosynthetic prokaryotes that have existed on Earth for an estimated 2.7 billion years. The ability of cyanobacteria to produce oxygen initiated the transition from a planet consisting of high levels of carbon dioxide and little oxygen, to what has been called the Great Oxygenation Event where large amounts of oxygen gas were produced. [4]
The Great Oxidation Event (GOE) or Great Oxygenation Event, also called the Oxygen Catastrophe, Oxygen Revolution, Oxygen Crisis or Oxygen Holocaust, [2] was a time interval during the Earth's Paleoproterozoic era when the Earth's atmosphere and shallow seas first experienced a rise in the concentration of free oxygen. [3]
Cyanobacteria become the first oxygen producers 2.4 – 2.3 billion years ago Earliest evidence (from rocks) that oxygen was in the atmosphere 1.2 billion years ago Red and brown algae become structurally more complex than bacteria 0.75 billion years ago Green algae outperform red and brown algae in the strong light of shallow water
Further chemical and isotopic analysis of ancient rock reveals that by the Siderian period, roughly 2.45 billion years ago, [5] oxygen had appeared. This indicates that oceanic, photosynthetic cyanobacteria evolved during this period because they were the first microbes to produce oxygen as a byproduct of their metabolic process. [6]
Between 2.5 and 3.0 billion years ago, cyanobacteria started using the energy from light to split water, releasing oxygen into the anaerobic, reducing environment. [5] [8] Parts of this ancient cyanobacterial metabolism are still maintained today. [8] Bandyopadhyay et al. 2011 created a phylogenic tree for cyanobacteria using 226 homolog ...
Oxygen evolution is the chemical process of generating elemental diatomic oxygen (O 2) by a chemical reaction, usually from water, the most abundant oxide compound in the universe. Oxygen evolution on Earth is effected by biotic oxygenic photosynthesis , photodissociation , hydroelectrolysis , and thermal decomposition of various oxides and ...
As cyanobacteria are bacteria that use light to fuel their energy-producing photosynthetic machinery they depend on perceiving light in order to optimize their response and to avoid harmful light that could result in the formation of reactive oxygen species and subsequently in their death. [28]