User:Czeer/nickel biology

Biological role
Although not recognized until the 1970s, nickel is known to play an important role in the biology of some plants, eubacteria, archaebacteria, and fungi. Nickel enzymes such as urease are considered virulence factors in some organisms.

Urease is the only known nickel enzyme in eukarya, and catalyzes the hydrolysis of urea to form ammonia and carbamate. The [NiFe]-hydrogenases can catalyze the oxidation of to form protons and electrons, and can also catalyze the reverse reaction, the reduction of protons to form hydrogen gas. A nickel-tetrapyrrole coenzyme, cofactor F430, is present in methyl coenzyme M reductase, which can catalyze the formation of methane, or the reverse reaction, in methanogenic archaea. One of the carbon monoxide dehydrogenase enzymes consists of an Fe-Ni-S cluster. Other nickel-bearing enzymes include a rare bacterial class of superoxide dismutase and glyoxalase I enzymes in bacteria and several parasitic eukaryotic trypanosomal parasites (in higher organisms, including yeast and mammals, this enzyme divalent zincZn2+).

Nickel is implicated in the catalytic formation of the hard calcium carbonate plates of the spiny tests on larval sea urchins.

Nickel can affect human health through infections by nickel-dependent bacteria. Nickel released from Siberian Traps volcanic eruptions (site of the modern city of Norilsk) is suspected of assisting the growth of Methanosarcina, a genus of euryarchaeote archaea that produced methane during the biggest extinction event on record.