O-methylation

functional group consisting of a methyl group bound to oxygen

thumb|350px|Norepinephrine degradation. Catechol-O-methyltransferase is shown in green boxes. 'Catechol-O-methyltransferase (COMT'; ) is one of several enzymes that degrade catecholamines (neurotransmitters such as dopamine, epinephrine, and norepinephrine), catecholestrogens, and various drugs and substances having a catechol structure. In humans, catechol-O-methyltransferase protein is encoded by the COMT gene. Two isoforms of COMT are produced: the soluble short form (S-COMT) and the membrane bound long form (MB-COMT). As the regulation of catecholamines is impaired in a number of medical c

thumb|2'-O-methyl-adenosine, a modified adenosine. '''2'-O-methylation (2'-O-Me''') is a nucleotide epitranscriptomics modification commonly found in ribosomal RNA (rRNA), transfer RNA (tRNA), and small nuclear RNA (snRNA). This modification is created through post-transcriptional modification of the RNA. This modification can be performed via ribonucleoprotein (snoRNP) with C/D box small nucleolar RNA (snoRNA) used as a guide RNA where a methyl group is added to the 2' hydroxyl of the ribose moiety of any nucleotide (Nm) producing a methoxy group. It can also be performed through other enzyme

class of enzymes