It's not magnesium, but salts of this element are added to promote mutagenesis in error-prone PCR reactions.
In the human brain, this element is mainly found bound to glutamine synthetase in astrocytes. This element and zinc are used as cofactors by an enzyme that participates in homocysteine metabolism and whose product is the methylated form of S-adenosylmethionine. It's not magnesium, but salts of this element are added to promote mutagenesis in error-prone PCR reactions. Chronic inhaled exposure to excess levels of this element causes an illness that resembles idiopathic Parkinson's disease and is treated with levodopa and (*) EDTA chelation. 2-amino-6-borohexonic acid inhibits a Urea cycle enzyme that uses this element as a cofactor to produce ornithine and urea from arginine. It's not calcium, but the oxygen-evolving complex (OEC) present in photosystem II has a metalloenzyme core containing of four atoms of this element. As an alternative to osmium tetroxide, an ion containing this element bound to four oxygens can be used to oxidize alkenes to diols. For 10 points, name this transition metal which is found in the +7 oxidation state in a purple salt used in redox chemistry.
In the human brain, this element is mainly found bound to glutamine synthetase in astrocytes.
Manganese or Mn