Alicyclobacillus used to be the problem (for fruit juice manufacturers). Now is the solution (for CRISPR-diagnostics). Read the MIT News on STOPCovid, the first FDA-approved test based on CRISPR. Here’s an extract.

“The full test — both the viral genome amplification and subsequent detection — can be completed in a single reaction, from swabs or saliva. To engineer this, the team tested a number of CRISPR enzymes to find one that works well at the same temperature needed by the enzymes that perform the amplification. Zhang, Abudayyeh, Gootenberg, and their teams, including graduate students Julia Joung and Alim Ladha, settled on a protein called AapCas12b, a CRISPR protein from the bacterium Alicyclobacillus acidophilus, responsible for the “off” taste associated with spoiled orange juice. With AapCas12b, the team was able to develop a test that can be performed at a constant temperature and does not require opening tubes midway through the process, a step that often leads to contamination and unreliable test results”.