pfam08459: UvrC_RNaseH_dom (This model is not part of the current CDD release)
UvrC RNAse H endonuclease domain
This domain is found in the C subunits of the bacterial and archaeal UvrABC system which catalyzes nucleotide excision repair in a multi-step process. UvrC catalyzes the first incision on the fourth or fifth phosphodiester bond 3' and on the eighth phosphodiester bond 5' from the damage that is to be excised. The domain described here represents the RNAse H endonuclease domain, located at the C-terminal, between the UvrBC and the (HhH)2 domains, nearby the N-terminal of the HhH. Despite the lack of sequence homology, the endonuclease domain has an RNase H-like fold, which is characteristic of enzymes with nuclease or polynucleotide transferase activities. RNase H-related enzymes typically contain a highly conserved carboxylate triad, usually DDE, in their catalytic centre. However, instead of a third carboxylate, UvrC of Thermotoga maritima was found to contain a highly conserved histidine (H488) on helix-4 in close proximity to two aspartates.
Jiyao W et al.(2023). "The conserved domain database in 2023.",