Methylation

 In the chemical sciences, methylation denotes the addition of a methyl on a substrate, or the substitution of an atom (or group) by a methyl . Methylation may be a sort of alkylation, with a methyl replacing a atom . These terms are commonly utilized in chemistry, biochemistry, soil science, and therefore the biological sciences.   In biological systems, methylation is catalyzed by enzymes; such methylation are often involved in modification of heavy metals, regulation of organic phenomenon , regulation of protein function, and RNA processing. In vitro methylation of tissue samples is additionally one method for reducing certain histological staining artifacts. The counterpart of methylation is named demethylation. along side ubiquitin and phosphorylation, methylation may be a major biochemical process for modifying protein function. the foremost prevalent protein methylations produce specific histones from arginine and lysine. Otherwise histidine, glutamate, asparagine, cysteine are vulnerable to methylation. a number of these products include S-methylcysteine, two isomers of N-methylhistidine, and two isomers of N-methylarginine. Methionine synthase regenerates methionine (Met) from homocysteine (Hcy). the general reaction transforms 5-methyltetrahydrofolate (N5-MeTHF) into tetrahydrofolate (THF) while transferring a methyl to Hcy to make Met. Methionine Synthases are often cobalamin-dependent and cobalamin-independent: Plants have both, animals depend upon the methylcobalamin-dependent form.25. Methylation Peer-review Journals