Nukaya H, Koyota S, Jinno F, Ishida H, Wakabayashi K, Kurosaka R, Kim I S, Yamaizumi Z, Ushiyama H, Sugimura T
School of Pharmaceutical Science, University of Shizuoka, Japan.
Carcinogenesis. 1994 Jun;15(6):1151-4. doi: 10.1093/carcin/15.6.1151.
We previously found two new mutagens, compounds I and II, in bacteriological-grade beef extract by monitoring the mutagenicity to a new Salmonella strain, YG1024; compound I was identified as 2-amino-4-hydroxymethyl-3,8-dimethylimidazo[4,5-f]quinoxaline (4-CH2OH-8-MeIQx). In the present study, we isolated compound II from the beef extract, which accounted for 2% of the total mutagenicity of materials adsorbed on blue cotton. Further, we found that a large quantity of compound II was produced by heating a mixture of creatine, threonine and glucose (1:1:0.5) at 200 degrees C for 5 h, the level being 860-fold of that in the beef extract. The structure of this compound was determined to be 2-amino-1,7,9-trimethylimidazo[4,5-g]quinoxaline (7,9-DiMeIgQx) by X-ray crystallography. The amount of 7,9-DiMeIgQx in bacteriological-grade beef extract was estimated to be 53 ng/g. This compound induced 13 800 and 670 revertants of S. typhimurium YG1024 and TA98 respectively, per micrograms in the presence of S9 mix.
我们之前通过监测对一种新的沙门氏菌菌株YG1024的诱变性，在细菌学级牛肉提取物中发现了两种新的诱变剂，化合物I和化合物II；化合物I被鉴定为2-氨基-4-羟甲基-3,8-二甲基咪唑并[4,5-f]喹喔啉（4-CH2OH-8-MeIQx）。在本研究中，我们从牛肉提取物中分离出化合物II，其占吸附在蓝色棉上的物质总诱变性的2%。此外，我们发现通过将肌酸、苏氨酸和葡萄糖（1:1:0.5）的混合物在200℃加热5小时可产生大量的化合物II，其含量是牛肉提取物中的860倍。通过X射线晶体学确定该化合物的结构为2-氨基-1,7,9-三甲基咪唑并[4,5-g]喹喔啉（7,9-DiMeIgQx）。细菌学级牛肉提取物中7,9-DiMeIgQx的含量估计为53 ng/g。在存在S9混合物的情况下，该化合物每微克分别诱导鼠伤寒沙门氏菌YG1024和TA98产生13800个和670个回复突变体。
