Biogenesis and DNA cargo of Dinoroseobacter shibae outer membrane vesicles suggests vesicle formation is coupled to replication

The Gram-negative photoheterotrophic bacterium Dinoroseobacter shibae is a member of the high abundant marine Roseobacter group. In the ocean, OMVs have about the same abundance as bacteria, a distinct depth distribution, and contain DNA from a variety of marine bacterial taxa. In the present study, we determined the abundance, size, and ultrastructure of membrane vesicles of D. shibae and analysed the protein inventory of the soluble and membrane fractions of cells and vesicles in order to study the origin of OMV membranes and content. The proteomic analyses were complemented by fatty acid analyses.

革兰氏阴性光能异养细菌施氏迪诺玫瑰杆菌（Dinoroseobacter shibae）是海洋中丰度较高的玫瑰杆菌类群的成员。在海洋环境中，外膜囊泡（Outer Membrane Vesicles，OMVs）的丰度与细菌大致相当，具有独特的深度分布特征，且携带多种海洋细菌类群的DNA。本研究中，我们测定了施氏迪诺玫瑰杆菌膜囊泡的丰度、尺寸与超微结构，并分析了菌体与囊泡的可溶性组分及膜组分的蛋白质组成，以探究外膜囊泡的膜结构与内含物的来源。本研究通过脂肪酸分析对蛋白质组学分析进行了补充。