Putative catalytic domain, repeat 1, of inactive veterbrate phospholipase PLD5
Putative catalytic domain, repeat 1, of inactive veterbrate phospholipases D5 (PLD5, EC 3.1.4.4), homologs of the vaccinia virus protein K4 encoded by the HindIII K4L gene. Vertebrate PLD5 has been assigned to the PLD superfamily, since it shows high sequence similarity to other human homologs of protein K4, which contain two copies of the conserved HKD motif (H-x-K-x(4)-D, where x represents any amino acid residue). However, due to the lack of functionally important histidine and lysine residues in the HKD motif, vetebrate PLD5 has been characterized as an inactive PLD.