Methylation cycle hypothesis MEpedia The Glutathione System: A Journey from Cyanobacteria to Higher Eukaryotes GLUTATHIONEtrying to learn more about it ** **The Methylation Cycle: ** After the methyl group gets transferred from L Methylfolate to the enzyme MTRR it is attached to "naked" B12 and this produces The effectiveness of compound X is oftentimes dependent on the presence of compounds Y and Z and so on. Endogenous compounds like glutathione get a lot of commercial attention but they do Components of the Glutathione Cycle as Markers of Biological Age: An Approach to Clinical Application in Aging