Biological Role
Although not recognized until the 1970s, nickel plays important roles in the biology of microorganisms and plants. In fact, urease (an enzyme that assists in the hydrolysis of urea) contains nickel. The NiFe-hydrogenases contain nickel in addition to iron-sulfur clusters. Such -hydrogenases characteristically oxidise H2. A nickel-tetrapyrrole coenzyme, Cofactor F430, is present in the methyl coenzyme M reductase, which powers methanogenic archaea. One of the carbon monoxide dehydrogenase enzymes consists of an Fe-Ni-S cluster. Other nickel-containing enzymes include a rare bacterial class of superoxide dismutase and glyoxalase I enzymes in bacteria and several parasitic eukaryotic trypanosomal parasites (this enzyme in higher organisms, including yeast and mammals, uses divalent zinc, Zn2+).
Read more about this topic: Nickel
Famous quotes containing the words biological and/or role:
“I am fifty-two years of age. I am a bishop in the Anglican Church, and a few people might be constrained to say that I was reasonably responsible. In the land of my birth I cannot vote, whereas a young person of eighteen can vote. And why? Because he or she possesses that wonderful biological attribute—a white skin.”
—Desmond Tutu (b. 1931)
“Where we come from in America no longer signifies—it’s where we go, and what we do when we get there, that tells us who we are.
The irony of the role of women in my business, and in so many other places, too, was that while we began by demanding that we be allowed to mimic the ways of men, we wound up knowing we would have to change those ways. Not only because those ways were not like ours, but because they simply did not work.”
—Anna Quindlen (b. 1952)