Escherichia coli genes affecting recipient ability in plasmid conjugation: Are there any?
Escherichia coli genes affecting recipient ability in plasmid conjugation: Are there any?
复制标题
DOI：
10.1186/1471-2164-10-71
复制
发表时间：
2009-02-09
期刊：
影响因子：
4.4
通讯作者：
de la Cruz, Fernando
中科院分区：
文献类型：
--
作者：
Perez-Mendoza, Daniel;de la Cruz, Fernando
背景：受体细胞如何参与细菌结合？为了回答这个问题，我们以质粒R388作为接合质粒，系统地分析了每个大肠杆菌基因在交配中的个体贡献。我们使用了自动偶联实验和两组大肠杆菌突变体收集：Keio收集（3908个大肠杆菌单基因缺失突变体）和大肠杆菌菌株DH5 α中随机收集的20,000个mini-Tn10::Km插入突变体。两种集合的结合使用确保了我们在调查中筛选了99%的大肠杆菌非必需基因。结果：不存在非必需受体大肠杆菌基因，这些基因在偶联过程中起重要作用。脂多糖（LPS）合成途径的突变对R388质粒转移的影响不大（占野生型的6-32%）。同样的突变对f质粒转移有强烈的抑制作用，但仅在液体交配中，这表明先前分离的共轭缺陷突变实际上损害了液体交配中的配对形成，但不影响共轭DNA的加工或运输本身。结论：我们从全基因组筛选中得出结论，受体细菌细胞不可避免地被用作细菌偶联的受体。这与抑制抗生素耐药性传播的问题有关，并表明偶联的作用就像一台纯粹的钻孔机，很少考虑受体细胞的构成。
Background: How does the recipient cell contribute to bacterial conjugation? To answer this question we systematically analyzed the individual contribution of each Escherichia coli gene in matings using plasmid R388 as a conjugative plasmid. We used an automated conjugation assay and two sets of E. coli mutant collections: the Keio collection ( 3,908 E. coli single-gene deletion mutants) and a collection of 20,000 random mini-Tn10::Km insertion mutants in E. coli strain DH5 alpha. The combined use of both collections assured that we screened >99% of the E. coli non-essential genes in our survey.Results: Results indicate that no non-essential recipient E. coli genes exist that play an essential role in conjugation. Mutations in the lipopolysaccharide (LPS) synthesis pathway had a modest effect on R388 plasmid transfer (6-32% of wild type). The same mutations showed a drastic inhibition effect on F-plasmid transfer, but only in liquid matings, suggesting that previously isolated conjugation-defective mutants do in fact impair mating pair formation in liquid mating, but not conjugative DNA processing or transport per se.Conclusion: We conclude from our genome-wide screen that recipient bacterial cells cannot avoid being used as recipients in bacterial conjugation. This is relevant as an indication of the problems in curbing the dissemination of antibiotic resistance and suggests that conjugation acts as a pure drilling machine, with little regard to the constitution of the recipient cell.