hUDG (human uracil DNA glycosylase)
hUDG is a recombinant, thermolabile enzyme that is obtained by expression of an artificially synthesized gene encoding human uracil-DNA glycosylase. This enzyme catalyzes the hydrolysis of the N-glycosylic bond between uracil and sugar leaving an apyrimidinic site. The enzyme works on the uracil-containing single-stranded and double-stranded DNA.
Due to its thermolability (loss of total activity in 5 min at 55 °C) hUDG is easily deactivated, e.g. in the PCR environment. While commonly used, UNG glycosylase, derived from E. coli is not completely inactivated during PCR, which may lead to degradation of the resulting PCR products based on mixtures containing dUTP.