HL-ExoI is a 3’-5’ exonuclease, specific for single stranded DNA. HL-ExoI is active at temperatures ≥25°C, and inactivated by 1 min incubation at 80°C, or 15 min at 60°C. Recombinantly produced in an E. coli strain expressing the HL-ExoI gene originating from an Arctic marine bacterium.
Unit definition: One unit catalyses the release of 10 nmol of acid soluble nucleotides in 30 min at 25°C. Reaction buffer: 20 mM Tris-HCl pH 7.5 at 25°C, 200 mM NaCl, 20 mM MgCl2, 1 mM DTT, 0.01% Triton X-100, 2.5% glycerol and 3H-dATP-labelled DNA (25 ng/µl).
Specific activity: >50 000 U/mg.
Storage buffer: 10 mM Tris-HCl pH 7.5 (at 25°C), 200 mM NaCl, 10 mM MgCl2, 1 mM DTT, 0.01% (v/v) Triton X-100, 50% (v/v) Glycerol.
Storage conditions: -20°C.