Bacterial shape
Bacterial shape
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DOI：
10.1046/j.1365-2958.2002.03111.x-i1
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发表时间：
2003-10
影响因子：
3.6
通讯作者：
K. Young
中科院分区：
文献类型：
--
作者：
K. Young
在自由生活的真细菌中，肽聚糖的外壳抵抗内部的静水压力，防止膜破裂和死亡。与此同时，这面墙给每个细胞施加了一种形状。因为形状是稳定的和可遗传的，就像许多生物体执行定义的形态转换的能力一样，细胞必须从大量可用形状中主动选择。他们如何做到这一点已经争论了几十年，但最近实验已经开始赶上理论。有两个发现特别具有启发性。首先，由FtsZ、MreB或Mbl成核的特定蛋白质组装体似乎充当影响细胞形状的内部支架，可能是通过正确定位合成酶。第二，细胞形状的缺陷与肽聚糖的不适当放置、代谢惰性斑块的存在相关。结合我们对影响细胞形态的突变体的了解，这些观察结果表明，细菌可以通过指导两种细胞壁的合成来制造特定的形状：一种是定义整体拓扑结构的长寿命刚性框架，另一种是代谢可塑性肽聚糖，其形状由内部支架指导。
In free-living eubacteria an external shell of peptidoglycan opposes internal hydrostatic pressure and prevents membrane rupture and death. At the same time, this wall imposes on each cell a shape. Because shape is both stable and heritable, as is the ability of many organisms to execute defined morphological transformations, cells must actively choose from among a large repertoire of available shapes. How they do so has been debated for decades, but recently experiment has begun to catch up with theory. Two discoveries are particularly informative. First, specific protein assemblies, nucleated by FtsZ, MreB or Mbl, appear to act as internal scaffolds that influence cell shape, perhaps by correctly localizing synthetic enzymes. Second, defects in cell shape are correlated with the presence of inappropriately placed, metabolically inert patches of peptidoglycan. When combined with what we know about mutants affecting cellular morphology, these observations suggest that bacteria may fabricate specific shapes by directing the synthesis of two kinds of cell wall: a long-lived, rigid framework that defines overall topology, and a metabolically plastic peptidoglycan whose shape is directed by internal scaffolds.