Vacuolar pathogens value membrane integrity.
Vacuolar pathogens value membrane integrity.
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液泡病原体重视膜的完整性。
DOI：
10.1073/pnas.1200326109
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发表时间：
2012
影响因子：
11.1
通讯作者：
Roy,CraigR
中科院分区：
文献类型：
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作者：
Roy,CraigR
细菌通常编码介导宿主细胞膜破坏的病毒决定簇;然而，空泡溶解和侵入宿主细胞胞质溶胶是仅少数细菌病原体用于细胞内复制的策略（1）。许多细菌病原体在专门的空泡中复制，这些空泡必须积极维持以防止这些细胞器与溶酶体融合，并在细菌复制期间调节用于空泡扩张的新膜的获得（2）。然而，为什么会这样呢？从理论上讲，细菌应该更容易裂解液泡并在胞质溶胶中复制。PNAS中的一项研究提供了新的数据，证明空泡完整性对嗜肺军团菌的细胞内存活很重要，并说明了宿主胞质溶胶的入侵如何在对抗细菌感染中发挥作用（3）。L.嗜肺菌普遍存在于淡水环境和土壤中。当军团菌被寄生原生动物宿主吞噬时，细菌迅速使用称为Dot/Icm的IV型分泌装置来递送大量促进细胞内存活和复制的效应蛋白（4）。基因组分析显示，在军团菌的不同种属和血清群中，编码这些效应物的基因库具有广泛的可塑性（5）。据认为，效应器可塑性在很大程度上是由原生动物宿主之间的遗传多样性驱动的，原生动物宿主在自然界中共同生活，
Bacteria commonly encode viru-lence determinants that mediate the disruption of host cell membranes; however, vacuole lysis and invasion of the host cell cytosol is a strategy used by only a select few bacterial pathogens for intracellular replication (1). Many bacterial pathogens replicate in specialized vacuoles that must be actively maintained to prevent these organelles from fusing with lysosomes and to regulate acquisition of new membrane for vacuole expansion during bacterial replication (2). However, why is this, when, in theory, it should be easier for a bacterium to lyse the vacuole and replicate in the cytosol? A study in PNAS provides new data that demonstrate that vacuole integrity is important for the intracellular survival of Legionella pneumophila and illustrate how invasion of the host cytosol can play a role in countering bacterial infection (3). L. pneumophila is found commonly in fresh water environments and soil. When Legionella are engulfed by parasitic protozoan hosts, the bacteria rapidly use a type IV secretion apparatus called Dot/Icm to deliver a large number of effector proteins that promote intracellular survival and replication (4). Genomic analysis has revealed extensive plasticity in the repertoire of genes encoding these effectors among different species and serogroups of Legionella (5). It is thought that effector plasticity is driven in large part by the genetic diversity among the protozoan hosts that cohabitate the environments in nature where