Insights into the molecular basis of L-form formation and survival in Escherichia coli.
Insights into the molecular basis of L-form formation and survival in Escherichia coli.
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DOI：
10.1371/journal.pone.0007316
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发表时间：
2009-10-06
期刊：
影响因子：
3.7
通讯作者：
Zhang Y
中科院分区：
文献类型：
--
作者：
Glover WA;Yang Y;Zhang Y
L型已被证明存在于许多种细菌中，并被怀疑与持续性感染有关。自1935年发现以来，已经进行了许多表征L型形态、生长和致病潜力的研究。然而，L型形成和存活的分子机制仍然未知。以大肠杆菌不稳定L型菌落为模型，进行全基因组转录组分析，筛选缺失突变体文库，研究L型形成和存活的分子机制。L型与经典菌落的微阵列分析揭示了许多未知功能的上调基因以及与持久细胞和生物膜共同共享的多个过度表达的应激途径。突变体筛选鉴定出三组突变体，它们在L型菌落形成中显示出不同程度的缺陷。第1组突变体，表现出最强的缺陷，在L型集落形成，属于参与细胞被膜应激，DNA修复，铁稳态，外膜生物合成，和药物外排/ABC转运的途径。四个（组1）突变体，rcsB，柯拉酸胶囊合成的正响应调节剂，ruvA，重组连接结合蛋白，毛皮，铁吸收调节剂和smpA小膜脂蛋白被选择用于互补。使用高拷贝过表达载体的突变体的互补失败，而利用低拷贝诱导型载体成功地恢复了L型形成。这项工作代表了第一个系统的基因和参与不稳定的L型细菌的形成和生存的途径的遗传评估。我们的研究结果为L型形成和存活的分子机制提供了新的见解，并对理解抗生素耐药性，细菌持久性和潜伏感染的出现以及设计新型药物和疫苗具有重要意义。
L-forms have been shown to occur among many species of bacteria and are suspected to be involved in persistent infections. Since their discovery in 1935, numerous studies characterizing L-form morphology, growth, and pathogenic potential have been conducted. However, the molecular mechanisms underlying the formation and survival of L-forms remain unknown. Using unstable L-form colonies of Escherichia coli as a model, we performed genome-wide transcriptome analysis and screened a deletion mutant library to study the molecular mechanisms involved in formation and survival of L-forms. Microarray analysis of L-form versus classical colonies revealed many up-regulated genes of unknown function as well as multiple over-expressed stress pathways shared in common with persister cells and biofilms. Mutant screens identified three groups of mutants which displayed varying degrees of defects in L-form colony formation. Group 1 mutants, which showed the strongest defect in L-form colony formation, belonged to pathways involved in cell envelope stress, DNA repair, iron homeostasis, outer membrane biogenesis, and drug efflux/ABC transporters. Four (Group 1) mutants, rcsB, a positive response regulator of colanic acid capsule synthesis, ruvA, a recombinational junction binding protein, fur, a ferric uptake regulator and smpA a small membrane lipoprotein were selected for complementation. Complementation of the mutants using a high-copy overexpression vector failed, while utilization of a low-copy inducible vector successfully restored L-form formation. This work represents the first systematic genetic evaluation of genes and pathways involved in the formation and survival of unstable L-form bacteria. Our findings provide new insights into the molecular mechanisms underlying L-form formation and survival and have implications for understanding the emergence of antibiotic resistance, bacterial persistence and latent infections and designing novel drugs and vaccines.
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影响因子：
12.3
作者：
Gentleman RC;Carey VJ;Bates DM;Bolstad B;Dettling M;Dudoit S;Ellis B;Gautier L;Ge Y;Gentry J;Hornik K;Hothorn T;Huber W;Iacus S;Irizarry R;Leisch F;Li C;Maechler M;Rossini AJ;Sawitzki G;Smith C;Smyth G;Tierney L;Yang JY;Zhang J
通讯作者：
Zhang J
影响因子：
64.5
作者：
Kohanski, Michael A.;Dwyer, Daniel J.;Collins, James J.
通讯作者：
Collins, James J.
影响因子：
--
作者：
DIENES, L;WEINBERGER, HJ
通讯作者：
WEINBERGER, HJ
影响因子：
4.4
作者：
Kvist, Malin;Hancock, Viktoria;Klemm, Per
通讯作者：
Klemm, Per
大肠杆菌K-12的构造框架，单基因敲除突变体：Keio Collection。
影响因子：
9.9
作者：
通讯作者：
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