Ramamurthi Kumaran S, Losick Richard
The Biological Laboratories, Department of Molecular and Cellular Biology, Harvard University, 16 Divinity Avenue, Cambridge, MA 02138, USA.
Mol Cell. 2008 Aug 8;31(3):406-14. doi: 10.1016/j.molcel.2008.05.030.
A hallmark of morphogenesis is the orchestrated assembly of complex, supramolecular structures. One such structure is the proteineous coat that surrounds spores of the bacterium Bacillus subtilis. The coat is a multilayered shell that is composed of more than 50 proteins. These proteins assemble around a basement layer composed of the morphogenetic protein SpoIVA. We show that SpoIVA harbors a Walker A box that is required for the proper deployment of the protein to the surface of the developing spore and proper assembly of the entire coat. We further show that purified SpoIVA both binds and hydrolyzes ATP and that the protein self-assembles into cable-like structures in a manner that depends on ATP hydrolysis. Self-assembly driven by ATP is an unusual mechanism for the construction of a large cellular structure.
形态发生的一个标志是复杂超分子结构的精心组装。一种这样的结构是围绕枯草芽孢杆菌孢子的蛋白质外壳。该外壳是一个多层壳，由50多种蛋白质组成。这些蛋白质围绕由形态发生蛋白SpoIVA组成的基底层组装。我们表明，SpoIVA含有一个沃克A框，这是该蛋白质正确部署到发育中孢子表面以及整个外壳正确组装所必需的。我们进一步表明，纯化的SpoIVA既能结合又能水解ATP，并且该蛋白质以依赖于ATP水解的方式自组装成丝状结构。由ATP驱动的自组装是构建大型细胞结构的一种不寻常机制。
