Petra Oyston is a Technical Fellow in the CBR Division at the Defence Science and Technology Laboratory (Dstl). Dstl’s role is to maximise the impact of S&T for the defence and security of the UK. Her research has focussed on developing medical countermeasures against biothreat agents, with an emphasis on the intracellular bacterial pathogens Yersinia pestis, Burkholderia pseudomallei and Francisella tularensis The aims of her work are the development of vaccines and the characterisation of bacterial processes that can be targeted by new classes of antimicrobials. Her particular interest lies in understanding gene regulation in these pathogens, how they adapt from environmental or vector niches to infect a mammalian host. In addition, she is Dstl’s lead on Synthetic Biology, with a role in identifying potential applications for this emerging and potentially disruptive technology to address some of the intractable problems faced by defence.