Envelope structure of Synechococcus sp. WH8113, a nonflagellated swimming cyanobacterium

被引：23

作者：

Samuel A.D.T. ^{[1
,2
]}

Petersen J.D. ^{[3
]}

Reese T.S. ^{[3
]}

机构：

[1] Rowland Institute for Science, Cambridge, MA

[2] Dept. of Molecular and Cell. Biology, Harvard University, Cambridge, MA

[3] Laboratory of Neurobiology, NIH, NINDS, Woods Hole, MA

来源：

BMC Microbiology | / 1卷 / 1期

关键词：

Outer Membrane; Cell Envelope; Outer Leaflet; Intramembrane Particle; Flagellar Filament;

D O I：

10.1186/1471-2180-1-4

中图分类号：

学科分类号：

摘要：

Background: Many bacteria swim by rotating helical flagellar filaments [1]. Waterbury et al. [15] discovered an exception, strains of the cyanobacterium Synechococcus that swim without flagella or visible changes in shape. Other species of cyanobacteria glide on surfaces [2,7]. The hypothesis that Synechococcus might swim using traveling surface waves [6,13] prompted this investigation. Results: Using quick-freeze electron microscopy, we have identified a crystalline surface layer that encloses the outer membrane of the motile strain Synechococcus sp. WH8113, the components of which are arranged in a rhomboid lattice. Spicules emerge in profusion from the layer and extend up to 150 nm into the surrounding fluid. These spicules also send extensions inwards to the inner cell membrane where motility is powered by an ion-motive force [17]. Conclusion: The envelope structure of Synechococcus sp. WH8113 provides new constraints on its motile mechanism. The spicules are well positioned to transduce energy at the cell membrane into mechanical work at the cell surface. One model is that an unidentified motor embedded in the cell membrane utilizes the spicules as oars to generate a traveling wave external to the surface layer in the manner of ciliated eukaryotes.

引用

页码：1 / 8

页数：7

共 17 条

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