Nukaya H, Iwami T, Ishida H, Tsuji K, Suwa Y, Wakabayashi K, Nagao M, Sugimura T, Kosuge T
School of Pharmaceutical Science, University of Shizuoka, Japan.
Mutat Res. 1990 Dec;245(4):251-7. doi: 10.1016/0165-7992(90)90154-c.
Coffee shows direct-acting mutagenicity in Salmonella typhimurium TA100 and most of this mutagenicity is due to the synergistic effects of methylglyoxal and hydrogen peroxide. The modifications of deoxyribonucleosides by methylglyoxal plus hydrogen peroxide were studied in vitro. When 2'-deoxyguanosine (6.25 mumole) was treated with methylglyoxal (125 mumole) and hydrogen peroxide (125 mumole) in 5 ml of 0.1 M phosphate buffer (pH 7.4) at 37 degrees C for 3 h, N2-acetyl-2'-deoxyguanosine was formed with a yield of 1.1%. Its formation increased time-dependently. By contrast, no appreciable modification of other deoxynucleosides was detected after their incubation with methylglyoxal and hydrogen peroxide under similar conditions. N2-Acetyl-2'-deoxyguanosine was also formed during incubation of 2'-deoxyguanosine with instant coffee.
咖啡在鼠伤寒沙门氏菌TA100中表现出直接致突变性，且这种致突变性大多归因于甲基乙二醛和过氧化氢的协同作用。体外研究了甲基乙二醛加过氧化氢对脱氧核糖核苷的修饰作用。当2'-脱氧鸟苷（6.25微摩尔）在5毫升0.1M磷酸盐缓冲液（pH 7.4）中，于37℃下与甲基乙二醛（125微摩尔）和过氧化氢（125微摩尔）反应3小时时，会形成N2-乙酰基-2'-脱氧鸟苷，产率为1.1%。其形成呈时间依赖性增加。相比之下，在类似条件下将其他脱氧核苷与甲基乙二醛和过氧化氢一起孵育后，未检测到明显的修饰。在2'-脱氧鸟苷与速溶咖啡孵育过程中也会形成N2-乙酰基-2'-脱氧鸟苷。
