The article focuses on the study conducted by Pascale Cossart to replicate the Rickettsia conorii, an intracellular bacterium. Cossart aims to identify the host proteins that bind R. conorii with the use of pull-down assay, in which lysates from mammalian cell lines were incubated with whole bacteria. The study found that internalization of R. conorii is mediated by its interaction with the protein Ku70 at the surface of host cells.