Measurement of Macromolecular Crowding in Rhodobacter sphaeroides under Different Growth Conditions.
Measurement of Macromolecular Crowding in Rhodobacter sphaeroides under Different Growth Conditions.
复制标题
不同生长条件下球形红杆菌大分子拥挤度的测定
DOI：
10.1128/mbio.03672-21
复制
发表时间：
2022-02-22
期刊：
影响因子：
6.4
通讯作者：
Armitage JP
中科院分区：
文献类型：
--
作者：
Khoo JH;Miller H;Armitage JP
细菌细胞质是一个非常拥挤的环境，拥挤的变化被认为对细胞过程有影响，包括蛋白质折叠，分子扩散和复合物的形成。先前关于拥挤效应的研究一般比较施加压力后的细胞活动。在非胁迫条件下，球形红杆菌对不同光强的响应会改变50纳米胞质膜（ICM）囊泡的数量，每个细胞的数量从几个到1000多个不等。本研究利用荧光共振能量转移（FRET）传感器和光激活定位显微镜（PALM）研究了ICM囊泡对光异养型球形红豆（r.s hahaeroides）的拥挤效应。在弱光下生长的细胞中，细胞质中有大量的ICM囊泡，FRET探针采用更浓缩的构象，与具有较少ICM囊泡的高光细胞相比，导致更高的FRET比率读数。通过PALM测定不同大小蛋白PAmCherry、PAmCherry- chey6和L1-PAmCherry的表观扩散系数显示，随着ICM囊泡数量的增加，蛋白分子>27 kDa的扩散减小。在拥挤程度高的弱光条件下，蛋白质分子的扩散速度比好氧细胞和强光细胞慢。这表明某些生理活动可能在不同的细菌种类中表现出不同的动力学，这些细菌种类的细胞膜组织可以随着生长条件的变化而变化。
The bacterial cytoplasm is a very crowded environment, and changes in crowding are thought to have an impact on cellular processes including protein folding, molecular diffusion and complex formation. Previous studies on the effects of crowding have generally compared cellular activity after imposition of stress. In response to different light intensities, in unstressed conditions, Rhodobacter sphaeroides changes the number of 50-nm intracytoplasmic membrane (ICM) vesicles, with the number varying from a few to over a thousand per cell. In this work, the effects of crowding induced by ICM vesicles in photoheterotrophic R. sphaeroides were investigated using a fluorescence resonance energy transfer (FRET) sensor and photoactivated localization microscopy (PALM). In low light grown cells where the cytoplasm has large numbers of ICM vesicles, the FRET probe adopts a more condensed conformation, resulting in higher FRET ratio readouts compared to high light cells with fewer ICM vesicles. The apparent diffusion coefficients of different sized proteins, PAmCherry, PAmCherry-CheY6, and L1-PAmCherry, measured via PALM showed that diffusion of protein molecules >27 kDa decreased as the number of ICM vesicles increased. In low light R. sphaeroides where the crowding level is high, protein molecules were found to diffuse more slowly than in aerobic and high light cells. This suggests that some physiological activities might show different kinetics in bacterial species whose intracellular membrane organization can change with growth conditions.
登录
查看更多内容
影响因子：
3.6
作者：
van den Bogaart, Geert;Hermans, Nicolaas;Poolman, Bert
通讯作者：
Poolman, Bert
影响因子：
1.2
作者：
Uphoff, Stephan;Sherratt, David J.;Kapanidis, Achillefs N.
通讯作者：
Kapanidis, Achillefs N.
影响因子：
56.9
作者：
Asbury, CL;Fehr, AN;Block, SM
通讯作者：
Block, SM
影响因子：
7.3
作者：
Miller H;Cosgrove J;Wollman AJM;Taylor E;Zhou Z;O'Toole PJ;Coles MC;Leake MC
通讯作者：
Leake MC
影响因子：
3.2
作者：
Neeli-Venkata, Ramakanth;Martikainen, Antti;Ribeiro, Andre S.
通讯作者：
Ribeiro, Andre S.