Soil inoculation and sampling.
All manipulations involving MTC organisms were performed in a Biosafety Level 3 laboratory (BSL3). A
clinical isolate of M. tuberculosis, M. canettii CIP140010059T and M. bovis CIP671203 was cultured on Middlebrook7H10 agar supplemented with oleic–albumin–glucose–catalase (OADC) (Becton Dickinson) and sodium pyruvate for culturing M. bovis at 37 uC in a 5% CO2-enriched atmosphere. Natural soil was collected in the Marseille area.