Metabolic cross-feeding via intercellular nanotubes among bacteria
Metabolic cross-feeding via intercellular nanotubes among bacteria
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DOI：
10.1038/ncomms7238
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发表时间：
2015-02-01
影响因子：
16.6
通讯作者：
Kost, Christian
中科院分区：
文献类型：
--
作者：
Pande, Samay;Shitut, Shraddha;Kost, Christian
细菌经常通过细胞外环境扩散来交换代谢物，但目前尚不清楚细菌是否也可以利用细胞与细胞的连接来直接交换营养物质。在这里，我们通过设计贝氏不动杆菌和大肠杆菌内部和之间的交叉喂养相互作用来解决这个问题，其中两种遥远的细菌物种相互交换必需氨基酸。我们确定，在充分混合的环境中，大肠杆菌（但可能不是 A. baylyi）可以通过膜衍生的纳米管连接到其他细菌细胞，并利用它们交换细胞质成分。细胞间连接由营养缺陷型突变诱导，并在外部提供氨基酸时停止建立。电子和荧光显微镜揭示了连接细菌细胞并实现细胞质材料的细胞间转移的纳米管结构网络。总之，我们的结果表明，细菌可以利用纳米管在相连的细胞之间交换营养物质，从而有助于在微生物群落内分配代谢功能。
Bacteria frequently exchange metabolites by diffusion through the extracellular environment, yet it remains generally unclear whether bacteria can also use cell-cell connections to directly exchange nutrients. Here we address this question by engineering cross-feeding interactions within and between Acinetobacter baylyi and Escherichia coli, in which two distant bacterial species reciprocally exchange essential amino acids. We establish that in a well-mixed environment E. coli, but likely not A. baylyi, can connect to other bacterial cells via membranederived nanotubes and use these to exchange cytoplasmic constituents. Intercellular connections are induced by auxotrophy-causing mutations and cease to establish when amino acids are externally supplied. Electron and fluorescence microscopy reveal a network of nanotubular structures that connects bacterial cells and enables an intercellular transfer of cytoplasmic materials. Together, our results demonstrate that bacteria can use nanotubes to exchange nutrients among connected cells and thus help to distribute metabolic functions within microbial communities.