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以野生型大肠菌ＣＳＨ５０及ｍｕｔＭ缺陷的大肠菌ＭＦ６７为宿主，观察了太阳光对Ｍ１３ｍｐ~２噬菌体单链ＤＮＡ ｌａｃＺα基因区域的致突变性．结果显示，太阳光照射引起噬菌体ｌａｃＺα基因区域的突变，在ｍｕｔＭ缺陷的宿主中更为明显；０．２５ｍｏｌ／Ｌ的甘露醇可以部分拮抗太阳光的致突变作用．以ＥＳＲ自旋捕捉法检测了太阳光、长波紫外线（ＵＶＡ）及中波紫外线（ＵＶＢ）照射Ｍ１３ｍｐ~２噬菌体样品中的自由基，结果还显示，太阳光和ＵＶＡ照射可引起羟自由基的产生，而ＵＴＢ照射则没有明显的自由基信号产生说明太阳光致突变作用与ＤＮＡ氧化损伤有关，羟自由基在其中发挥一定的作用
Wild-type coliforms CSH50 and mutM-deficient coliforms MF67 were used as hosts to observe the mutagenicity of sunlight on the lacZα gene region of M13mp ~ 2 phage ssDNA. The results showed that the mutation of lacZα gene in phage caused by sunlight was more obvious in mutM-deficient host; 0.25mol / L mannitol partially antagonized the mutagenic effect of sunlight. The free radicals in M13mp ~ 2 bacteriophage samples were detected by ESR spin-trapping method using sunlight, ultraviolet (UVA) and ultraviolet (UVB) radiation. The results also showed that sunlight and UVA irradiation could cause the generation of hydroxyl radicals , While there was no obvious signal of free radical generated by UTB irradiation, indicating that the solar mutagenesis was related to DNA oxidative damage, in which hydroxyl radical played a certain role