Taher M M, Lakshmaiah N
National Institute of Nutrition, Indian Council of Medical Research, Hyderabad, India.
J Inorg Biochem. 1987 Oct;31(2):133-41. doi: 10.1016/0162-0134(87)80058-2.
Folic acid is degraded by cytochrome c in the presence of hydrogen peroxide/tert-butyl hydroperoxide at the C9-N10 bond. The degradation is increased with increasing temperature. When guanidine HCl or benzoate are included in the reaction medium, the amount of folic acid degradation is enhanced. Catalase, formate, and thiourea inhibited hydrogen peroxide-dependent folic acid degradation only, and not tert-butyl hydroperoxide dependent degradation. Cyanide and azide markedly inhibited both the hydroperoxide-dependent degradations. Superoxide dismutase, EDTA, ethanol, mannitol, and dimethyl sulfoxide did not inhibit the degradation. The mechanism of cytochrome c-catalyzed folic acid degradation is discussed.
在过氧化氢/叔丁基过氧化氢存在的情况下，细胞色素c会使叶酸在C9-N10键处降解。降解程度随温度升高而增加。当反应介质中加入盐酸胍或苯甲酸盐时，叶酸的降解量会增加。过氧化氢酶、甲酸盐和硫脲仅抑制依赖过氧化氢的叶酸降解，而不抑制依赖叔丁基过氧化氢的降解。氰化物和叠氮化物显著抑制两种依赖氢过氧化物的降解。超氧化物歧化酶、乙二胺四乙酸、乙醇、甘露醇和二甲基亚砜不抑制降解。本文讨论了细胞色素c催化叶酸降解的机制。
