The release of nano-sized membrane vesicles is a property that has been conserved by multi- and unicellular organisms during evolution. One of the major functions of these vesicles is to facilitate intercellular communication and transport of molecules. It has been shown that many disease-causing bacteria produce vesicles and that one of the molecules found in these structures is DNA, yet the significance of these observations is unclear. The aims of the project are to characterise the DNA within bacterial vesicles and to determine how this DNA activates host innate immune responses. Thus, this research will provide new insights into bacterial infections representing major health and socio-economic burdens for animal hosts.