Surface tension-like forces determine bacterial shapes: Streptococcus faecium.
Surface tension-like forces determine bacterial shapes: Streptococcus faecium.
复制标题
类似表面张力的力决定细菌形状：屎链球菌。
DOI：
10.1099/00221287-123-1-151
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
Doyle,RJ
中科院分区：
文献类型：
--
作者：
Koch,AL;Higgins,ML;Doyle,RJ
使肥皂泡达到所包围体积的最小表面积的相同趋势似乎可以解释细菌（包括杆菌和球菌）生长和分裂的许多特征。只需要假设生长发生在区域中，并且只有在这些区域中，由静水压力引起的张力才产生迫使细胞增加壁面积的应变。由渗透压产生的应力产生应变，其显著降低通过水解或转移的键分裂的自由能。我们相信这足以使生长壁具有通常与表面张力有关的某些性质。所有细菌细胞壁生长的共同特征是肽聚糖在无菌株条件下插入。只有在共价键形成后，插入的受应力的肽键才断裂，使得新的单元支持由于静水压力引起的应力。这是一个特别简单的情况，有关形态学的详细数据是可用的。最适合的数据是通过假设生长发生在一个狭窄的区域附近的分裂隔膜和隔膜材料已经在张力下，因为它是外部化的，是两倍厚的外壁在整个发展的新生极。恒定的流体静压力的有效表面张力，P/T的比率，也是一致的电子显微镜观察。
The same tendency that causes soap bubbles to achieve a minimum surface area for the volume enclosed seems to account for many of the features of growth and division of bacteria, including both bacilli and cocci. It is only necessary to assume that growth takes place in zones and that only in these zones does the tension caused by hydrostatic pressure create the strain that forces the cell to increase the wall area. The stress developed by osmotic pressure creates strains that significantly lower the free energy of bond splitting by hydrolysis or transfer. We believe this is sufficient to make growing wall have some of the properties ordinarily associated with surface tension. The feature common to all bacterial cell wall growth is that peptidoglycan is inserted under strain-free conditions. Only after the covalent links have been formed are the intervening stressed peptide bonds cleaved so that the new unit supports the stress due to hydrostatic pressure.The present paper analyses the growth ofStreptococcus faeciumin these terms. This is a particularly simple case and detailed data concerning morphology are available. The best fit to the data is achieved by assuming that growth takes place in a narrow region near the splitting septum and that the septal material is already under tension as it is externalized and is twice as thick as the external wall throughout the development of the nascent poles. Constancy of the ratio of hydrostatic pressure to the effective surface tension,P/T, is also consistent with electron microscopic observations.