Kobayashi T, Takao M, Oikawa A, Yasui A
Research Institute for Tuberculosis and Cancer, Tohoku University, Sendai, Japan.
Mutat Res. 1990 Jul;236(1):27-34. doi: 10.1016/0921-8777(90)90029-5.
High-expression plasmids for photolyase (phr) genes from the bacteria Escherichia coli, Anacystis nidulans, Streptomyces griseus and Halobacterium halobium and the yeast Saccharomyces cerevisiae were constructed and introduced into E. coli phr recA cells. As previously reported, al introduced phr genes provided the host cells with photoreactivation-repair activity and the introduced E. coli phr gene rendered the host cells more UV-resistant in the dark. E. coli cells harboring foreign phr genes, however, were found to be more sensitive to UV light in the dark than cells containing the vector plasmid only. These differences in UV sensitivity in the dark disappeared when the host cells had an additional mutation, uvrA, suggesting that the foreign photolyases inhibited the E. coli excision-repair system.
构建了来自大肠杆菌、集胞藻、灰色链霉菌、嗜盐嗜盐菌和酿酒酵母的光解酶（phr）基因的高表达质粒，并将其导入大肠杆菌phr recA细胞。如先前报道，所有导入的phr基因都为宿主细胞提供了光复活修复活性，并且导入的大肠杆菌phr基因使宿主细胞在黑暗中对紫外线更具抗性。然而，发现携带外源phr基因的大肠杆菌细胞在黑暗中比仅含有载体质粒的细胞对紫外线更敏感。当宿主细胞有额外的uvrA突变时，黑暗中紫外线敏感性的这些差异消失了，这表明外源光解酶抑制了大肠杆菌的切除修复系统。
