Wilkins B M, Hollom S E, Rupp W D
J Bacteriol. 1971 Aug;107(2):505-12. doi: 10.1128/jb.107.2.505-512.1971.
Deoxyribonucleic acid (DNA) transfer from (3)H-thymine-labeled Hfr cells has been measured by determining the amount of radioactivity remaining after selective lysis of the donor cells in the mating mixture. DNA transfer was less effectively reduced by ultraviolet irradiation of excision-defective Hfr cells than was the yield of recombinants. The buoyant density of DNA transferred from unirradiated and irradiated Hfr cells was equivalent to that of double-stranded DNA. Mating-dependent DNA synthesis in the recipient has been measured by mating Hfr cells deficient in thymidine kinase with irradiated thymine-requiring F(-) cells in the presence of (3)H-thymine. The extent of such DNA synthesis approximated the amount of DNA transferred from unirradiated donors. Neither DNA transfer nor mating-dependent DNA synthesis could be reliably measured when both parents were irradiated. It is proposed that transferred Hfr DNA is replicated in the recipient and that this replication still occurs when the Hfr DNA contains dimers.
通过测定交配混合物中供体细胞经选择性裂解后剩余的放射性量，来测量来自用（³H）胸腺嘧啶标记的高频重组（Hfr）细胞的脱氧核糖核酸（DNA）转移情况。与重组体的产量相比，切除缺陷型Hfr细胞经紫外线照射后，DNA转移受到的影响较小。从未经照射和经照射的Hfr细胞转移的DNA的浮力密度与双链DNA的浮力密度相当。通过在（³H）胸腺嘧啶存在的情况下，将缺乏胸苷激酶的Hfr细胞与经照射的需要胸腺嘧啶的F⁻细胞进行交配，来测量受体中依赖交配的DNA合成。这种DNA合成的程度与从未经照射的供体转移的DNA量相近。当双亲都受到照射时，DNA转移和依赖交配的DNA合成均无法可靠测量。有人提出，转移的Hfr DNA在受体中复制，并且当Hfr DNA含有二聚体时这种复制仍会发生。
