Detection of Mycobacterium species

A method for detecting desired Mycobacterium species in a sample, the method comprising the steps of:

• a) mixing lytic mycobacteriophage-coupled paramagnetic particles with the sample to form a reaction mixture under conditions suitable to allow the mycobacteriophages to bind to any mycobacteriophage-sensitive Mycobacterium species present in the sample;
• b) applying a magnetic field to the sample to collect, and separate, mycobacteriophage-coupled paramagnetic particles with bound desired Mycobacterium species;
• c) incubating a suspension of the separated paramagnetic particles with bound Mycobacterium species under conditions to allow the lytic mycobacteriophage to replicate inside viable Mycobacterium species cells and to lyse the viable Mycobacterium species cells;
• d) recovering, from the incubated suspension, nucleic acid of lysed Mycobacterium species;
• and
• e) analysing the nucleic acid released from the lysed Mycobacterium species to identify a signature nucleotide sequence that occurs in the desired Mycobacterium species;
• in which following step c), the incubated suspension is subjected to heat shock conditions of about 55° C. for about 1 minute to maximise release of nucleic acids from phage-lysed mycobacterial cells before centrifuging the incubated suspension to recover DNA of the lysed Mycobacterium species into a supernatant phase.