Woods W G, Dyall-Smith M L
Department of Microbiology, University of Melbourne, Parkville, Australia.
Mol Microbiol. 1997 Feb;23(4):791-7. doi: 10.1046/j.1365-2958.1997.2651626.x.
By deleting the radA open reading frame of an extreme halophile, Haloferax volcanii, we created and characterized a recombination-deficient archaeon. This strain, Hf. volcanii DS52, has no detectable DNA recombination, is more sensitive to DNA damage by UV light and ethylmethane sulfonate, and has a slower growth rate than the wild type. These characteristics are similar to those observed in recombination mutants of Eukarya and Bacteria, and show that the radA gene belongs in the recA/RAD51 family by function as well as sequence homology. In addition, strain DS52 was not transformable by plasmids pWL102 or pUBP2 (which contain pHV2 and pHH1 replicons, respectively), although it was readily transformed by plasmids containing a pHK2 replicon, indicating a role for radA in the maintenance or replication of some halobacterial plasmids. Despite its slower growth rate, Hf. volcanii DS52 was still easy to culture and transform, and should be suitable for use in studies where a recombination-deficient background is desired.
通过删除嗜极嗜盐菌沃氏嗜盐栖热菌（Haloferax volcanii）的radA开放阅读框，我们构建并鉴定了一株重组缺陷型古菌。该菌株，即沃氏嗜盐栖热菌DS52，未检测到DNA重组，对紫外线和甲基磺酸乙酯造成的DNA损伤更为敏感，且生长速度比野生型慢。这些特征与在真核生物和细菌的重组突变体中观察到的特征相似，表明radA基因在功能以及序列同源性方面属于recA/RAD51家族。此外，DS52菌株不能被质粒pWL102或pUBP2（分别含有pHV2和pHH1复制子）转化，尽管它很容易被含有pHK2复制子的质粒转化，这表明radA在某些嗜盐菌质粒的维持或复制中发挥作用。尽管沃氏嗜盐栖热菌DS52生长速度较慢，但仍然易于培养和转化，应该适用于需要重组缺陷背景的研究。
