Cryogenic Grinding for Mechanical Abrasion for Hardy Endospores

A comparative analysis was carried out between an emerging cryogenic grinding method and a conventional wetchemistry/ bead-beating endospore disruption approach. After extensive trial and error, it was determined that a regimen of three cryogenic grinding cycles of 2 minutes each was optimum for downstream DNA recovery. Spores embedded in ice exhibited a mere 1-log reduction in recovery following cryomilling for up to 30 minutes. The observed total spore-borne DNA recovery was quite impressive, as well established, streamlined techniques for extracting DNA from endospores typically recover, at best, ≈10% of the molecules present. To facilitate the nucleic-acid-based testing required to detect and quantify DNA and endospores recovered, this innovation implements cryogenic grinding procedures followed by qPCR (quantitative polymerase chain reaction) methods to verify this novel capture technique.