homocysteine Chem.
(hɒməʊˈsɪstiːn, -ˈsɪstiːɪn)
[f. homo- b + cysteine.]
An amino-acid, HS·CH2·CH2·CH(NH2)·COOH, which is important as an intermediate in the metabolism of methionine and cysteine.
| 1932 Jrnl. Biol. Chem. XCIX. 137 If the hydrolysis, however, should take place between the methyl group and the sulfur then methyl alcohol and homocysteine would result. 1935 Ibid. CXII. 149 (heading) The isolation of homocysteine and its conversion to a thiolactone. 1962 Biochem. & Biophys. Res. Comm. IX. 493 The normal pathway for the metabolism of methionine involves demethylation to homocysteine which in turn combines with serine to form cystathionine, an intermediate along the pathway to cysteine and cystine. |