Comment | This highly divergent, uncharacterized domain has several absolutely conserved residues, including a QR pair and FxxxN motif. Its most striking feature, however, is a near invariant pentapeptide motif DGQHR. Several different subfamilies occur specifically as a part of DNA phosphorothioation systems, previously called DND (DNA instability during electrophoresis), while others (e.g. CPS_2936) occur in other contexts suggestive of lateral gene transfer (sporadic distribution of helicase-containing cassettes). The region described by this model is about 280 amino acids in length; additional sequences show local sequence similarity. |