Properties of Escherichia coli expressing bacteriophage P22 Abc (anti-RecBCD) proteins, including inhibition of Chi activity.
Properties of Escherichia coli expressing bacteriophage P22 Abc (anti-RecBCD) proteins, including inhibition of Chi activity.
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表达噬菌体 P22 Abc（抗 RecBCD）蛋白的大肠杆菌的特性，包括抑制 Chi 活性。
DOI：
10.1128/jb.175.6.1756-1766.1993
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发表时间：
1993
影响因子：
3.2
通讯作者：
Lewis,LJ
中科院分区：
文献类型：
--
作者：
Murphy,KC;Lewis,LJ
携带表达噬菌体P22抗RecBCD功能abc 1和abc 2的质粒的大肠杆菌菌株被测试recBC样表型的存在。Abc 2在野生型和recD突变株中诱导对UV光的中度敏感性，但严重地使recF和recJ突变株敏感。Abc 1在野生型或recF或recJ突变宿主中对UV敏感性几乎没有影响，但使recD突变体对20 J/m2的UV剂量的敏感性增加约10倍。Abc 2诱导E.大肠杆菌分离生长过程中的活细胞，干扰λ红gam chi+和chi 0噬菌体的生长（chi+噬菌体的作用更大），抑制λ红gam杂交测定的Chi和Chi样活性，并阻止响应萘啶酸的SOS诱导; Abc 1在这些试验中没有作用。Abc 2单独或与Abc 1一起，在P2前噬菌体存在下不允许λ红gam生长，但不杀死P2溶原性宿主（如λ Gam）。最后，Abc 2抑制野生型细胞中的接合重组到recBC突变体中所见的水平。这些数据表明，Abc 2抑制RecBCD的重组促进能力，但保持核酸外切酶功能完整。
Escherichia coli strains bearing plasmids expressing phage P22 anti-RecBCD functions abc1 and abc2 were tested for the presence of recBC-like phenotypes. Abc2 induces moderate sensitivity to UV light in wild-type and recD mutant strains but severely sensitizes both recF and recJ mutants. Abc1 has little effect on UV sensitivity in wild-type or recF or recJ mutant hosts but increases the sensitivity of recD mutants to a UV dose of 20 J/m2 about 10-fold. Abc2 induces E. coli to segregate inviable cells during growth, interferes with the growth of lambda red gam chi+ and chi 0 phage (the effect is greater with chi+ phage), inhibits Chi and Chi-like activity as measured by lambda red gam crosses, and prevents SOS induction in response to nalidixic acid; Abc1 has no effect in these tests. Abc2, alone or with Abc1, does not allow the growth of lambda red gam in the presence of a P2 prophage but does not kill the P2 lysogenic host (as lambda Gam does). Finally, Abc2 inhibits conjugational recombination in wild-type cells to the level seen in recBC mutants. These data suggest that Abc2 inhibits the recombination-promoting ability of RecBCD but leaves the exonuclease functions intact.