Homocysteine occurrence

Enzymatic methylation of homocysteine (HSCHjCHjCHNHjCOOH) by methylcobalamin to give methionine (CH3SCH2CH2CHNH2COOH) was discovered in 1962 by Woods and co-workers, who also noticed the occurrence of a much slower, nonenzymatic reaction giving the same products. Methylcobinamide showed the same activity as the cobalamin in both the enzymatic and nonenzymatic reactions (72, 7/). It was subsequently discovered that HS, MeS , PhS , and w-BuS will dealkylate a variety of methyl complexes [DMG, DMG-BF2, DPG, G, salen, (DO)(DOH)pn, cobalamin] and even ethyl-Co(DMG)2 complexes to give the thioethers, and it was suggested that the reaction involved transfer of the carbonium ion to the attacking thiolate 161, 164), e.g.,... 

Marcucci R, et al. PAI-1 and homocysteine, but not lipoprotein (a) nor thrombophilic polymorphism, are associated with the occurrence of major adverse cardiac events after successful coronary stenting. Heart 2005 92(3) 377—381. 

In chapter 3, we briefly discussed the link between elevated homocysteine levels, increased acidity, and, ultimately, cardiovascular problems. While additional studies are required, promising scientific evidence suggests that folate (also known as vitamin Bg), vitamin B6, and vitamin BI2 are effective at lowering homocysteine levels and may ultimately play a role in reducing vascular disease. In addition, research has revealed an inverse relationship between folate and the occurrence of colorectal cancer.5 (In other words, the more deficient in folate you are, the greater your risk of colorectal cancer.)... 

Dudman NP, Wilcken DE, Wang J, Lynch JF, Macey D, Lundberg P. Disordered methionine/ homocysteine metabolism in premature vascular disease. Its occurrence, cofactor therapy and enzymology. Arterioscler Thromb 1993 13 1253-1260. 

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