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         Like many discoveries, this was not the result of purposeful research, but rather a sudden and very interesting branch in another, equally important, pilot experiment - a study of anaerobic methane oxidation associated with nitrites and nitrates.
         Currently, there are three known ways of biological production of oxygen: photosynthesis, bacterial intracellular conversion chlorates and the detoxification of reactive oxygen species. During the aforementioned study were found microbes, similar in structure to the previously found in the caves of limestone monolith Nullarbor (Australia) and belonging to a group of NC10, but still poorly understood. This bacterium, named "Candidatus Methylomirabilis oxyfera", has very interesting properties, one of which is responsible for the reaction of aerobic oxidation of methane. Grown together with other microorganisms, "Candidatus Methylomirabilis oxyfera" in the bioreactor allowed the reconstruction of its structure on DNA samples extracted from the mixture. It was found that with a certain area of the genomes of bacteria has the ability to reduces nitrite via the recombination of two molecules of nitric oxide(2NO - (fig.2)) into nitrogen and oxygen, bypassing the familiar denitrification intermediate nitrous oxide(NO₃^-→NO₂^-→NO→N₂O→N₂). At the same bacteria are secrete in a nitrogen atmosphere as a byproduct of the reaction and part of the received of oxygen, the remainder of the oxygen used in the further oxidation of methane for energy. Finding ways of biochemical oxygen production to date is completely unknown, in fact the 4 way. There are a number of assumptions, how the organism carries out such processes, but not yet received any pure culture of bacteria or enzymes, which control the reaction to produce oxygen. Analysis of genotype allowed to assume the structure of the enzyme and assured itself of researchers will soon be obtained and identified: "We don't have an enzyme but we have possible genes in the genome that might be that enzyme."  
         This discovery brings us to the fact that at an early stage of nucleation of the Earth, with her without oxygen, but methane-rich atmosphere, already in place the processes of microbial metabolism. Oxygen, at that time, could already be available for the microbes with a similar plot of the genome of the nitrogen oxides present in abundance in the atmosphere due to volcanic activity of the planet. Earlier it was believed that this occurred only when there is independent of oxygen atoms in the circulation of the environment by running in a chlorophyll-containing cells of photosynthesis. Also, this discovery has implications for scientists studying the circulation of methane on Earth.