During the first half of the 20th century, F. Griffith discovered natural (Griffith, 1928) while J. Lederberg and E. Tatum discovered bacterial conjugation (Lederberg & Tatum, 1946). These seminal findings opened the molecular biology area by contributing to the identification of the molecule transferred during these processes and carrying the genetic information: DNA (Avery et al, 1944).
Nowadays, we know that natural transformation and conjugation are two highly efficient processes that promote bacterial genome plasticity and adaptive response. They are essential for bacterial survival and greatly limit the efficiency of antibiotic treatments or vaccines against some pathogenic bacteria.
Molecular devices mediating DNA translocation through the cellular envelope during conjugation and transformation have been identified. However, more than 50 years after the discovery of bacterial conjugation and transformation, the molecular details of DNA translocation during these two processes remain elusive.
The group “Structural biology of bacterial secretion” was created in October 2009 at the Institut Pasteur. We use structural biology (X-ray crystallography and high-resolution electron microscopy) and biochemistry techniques to study the structure of the membrane protein complexes involved in these events.