甲醛致酵母菌与大肠杆菌DNA-蛋白质交联作用的比较

A Comparison between the effects on DNA-protein cross-links of Saccharomyces and E.coli induced by formaldehyde

摘要:

为了探讨甲醛致真核生物与原核生物DNA-蛋白质交联(DNA-protein crosslinks,DPC)的作用,以毕赤酵母(Pichia pastoris)和大肠杆菌(Escherichia coli)DH5α为材料,采用KCl-SDS沉淀法检测液态甲醛染毒后酵母菌与大肠杆菌中DPC含量。结果表明,低浓度(25μmol/L)甲醛不能引起酵母菌和大肠杆菌的DPC(P>0.05),而较高浓度(125和625μmol/L)甲醛可引起酵母菌和大肠杆菌明显的DPC(P<0.05);另外,酵母菌的DPC系数是大肠杆菌的DPC系数的10倍左右。这表明甲醛致真核细胞和原核细胞的DPC作用具有剂量效应关系,而且真核细胞的DPC系数比原核细胞的DPC系数更高。

Abstract:

To explore the effect of formaldehyde on DNA-protein cross-links (DPC) in eucaryotic cells and prokaryotic cells, Pichia pastoris and E.coli DH5α were chosen as materials to evaluate the amount of DPC induced by liquid formaldehyde in vivo by the method of KCl-SDS assay. The results showed that formaldehyde could not induce DPC at low dose(25μmol/L，P＞0.05), but could obviously induce DPC at higher dose (125 and 625μmol/L，P＜0.05). The DPC coefficient in Pichia pastoris was 10-fold higher than that in E.coli DH5α. It is concluded that formaldehyde could induce DPC in eucaryotic cells and prokaryotic cells with a dose-dependent manner and the DPC coefficient in Pichia pastoris is higher than that in E.coli DH5α.