Method for producing extra-chromosomal nucleic acid molecules

A method for producing a microbial clear lysate comprising the steps of:

• (a) mixing a suspension of microorganisms and an extraction buffer at a mixing point, wherein the mixing point is a T-form having at least two inlets opposing each other at an angle of 180° and an outlet that is located perpendicular to and between the two inlets;
• (b) reacting the mixture of step (a) for a duration sufficient to break up the microorganisms, wherein the reacting is performed within a volume element connected directly to the outlet of the mixing point at a linear flow rate of between 280 and 900 cm per minute;
• (c) transferring the mixture of step (b) into a vessel comprising a neutralizing buffer to facilitate the formation of a precipitate and the microbial clear lysate, wherein the precipitate comprises cell debris and genomic DNA and the microbial clear lysate comprises extra-chromosomal nucleic acid;
• and
• (d) generating gas bubbles by dispersing a gas through the bottom of the vessel to separate the precipitate from the microbial clear lysate by flotation, wherein the gas influx leads to the formation of the gas bubbles to which the precipitate adsorbs thus ascending to form a foam layer on top of the neutralizing buffer.