Thermostable Endonuclease Q is active between 37 – 90°C, but has optimal activity between 65°C and 85°C. Temperature profile Thermostable Endonuclease Q is active over a wide range of temperatures. Thermostable Endonuclease Q (#M0701, 0.2 U) activity was tested on 1 pmol of a fluorescently-labeled single-stranded oligonucleotide containing a single uracil for 1 hour in 1x NEBuffer r2.1 at various temperatures. Cleaved products were detected by capillary electrophoresis. Thermostable Endonuclease Q is active over a wide range of temperatures (37°C – 90°C), but displays optimal activity between 65°C and 85°C.