About the Authors
Microbial Evolutionary Genomics, Institut Pasteur, CNRS, URA2171, Paris, France
Atelier de BioInformatique, UPMC Univ Paris 06, Paris, France
The authors have declared that no competing interests exist.
Conceived and designed the experiments: SVS EPCR. Performed the experiments: SVS. Analyzed the data: SVS. Contributed reagents/materials/analysis tools: SVS EPCR. Wrote the paper: SVS EPCR.