Homocysteine

Homocysteine is a non-protein amino acid. It is a homologue of the amino acid cysteine, differing by an additional methylene (-CH2-) group. It is biosynthesized from methionine by the removal of its terminal Cε methyl group. Homocysteine can be recycled into methionine or converted into cysteine with the aid of B-vitamins.

While detection of high levels of homocysteine has been linked to cardiovascular disease, lowering homocysteine levels may not improve outcomes.

Read more about HomocysteineHealth Effects, Structure, Biosynthesis and Biochemical Roles

Other articles related to "homocysteine":

Serine Dehydratase - Inhibitors
... Homocysteine, a compound that SDH combines with Serine to create cystathionine, also noncompetitively inhibits the action of SDH ... Studies have shown that homocysteine reacts with SDH's PLP coenzyme to create a complex ... In general, homocysteine is an amino acid and metabolite of methionine increased levels of homocysteine can lead to homocystinuria(see section Disease Relevance) ...
Cystathionine Beta-lyase
... that catalyzes the chemical reaction L-cystathionine + H2O L-homocysteine + NH3 + pyruvate Thus, the two substrates of this enzyme are L-cystathionine and H2O, whereas its 3 products are L-homocysteine, NH3, and ... name of this enzyme class is L-cystathionine L-homocysteine-lyase (deaminating pyruvate-forming) ... cystine lyase, cystathionine L-homocysteine-lyase (deaminating), and L-cystathionine L-homocysteine-lyase (deaminating) ...
Homocysteine - Biosynthesis and Biochemical Roles - Other Reactions of Biochemical Significance
... Homocysteine can cyclize to give homocysteine thiolactone, a five-membered heterocycle ... Because of this "self-looping" reaction, homocysteine-containing peptides tend to cleave themselves by reactions generating oxidative stress ...
S-adenosylhomocysteine Deaminase
... EC 3.5.4.28) is an enzyme that catalyzes the chemical reaction S-adenosyl-L-homocysteine + H2O S-inosyl-L-homocysteine + NH3 Thus, the two substrates of this enzyme are S-adenosyl-L-homocysteine and ... name of this enzyme class is S-adenosyl-L-homocysteine aminohydrolase ...
S-ribosylhomocysteine Lyase
... is an enzyme that catalyzes the chemical reaction S-(5-deoxy-D-ribos-5-yl)-L-homocysteine L-homocysteine + (4S)-4,5-dihydroxypentan-2,3-dione Hence, this enzyme has one substrate, S-(5-deoxy-D-ribos-5-yl)-L-homocyst ... The systematic name of this enzyme class is S-(5-deoxy-D-ribos-5-yl)-L-homocysteine L-homocysteine-lyase ... LuxS converts S-ribosylhomocysteine to homocysteine and 4,5-dihydroxy-2,3-pentanedione (DPD) DPD can then spontaneously cyclise to active AI-2 ...