<p>This entry represents a small and phylogenetically curious clade of sequences. Sequences are found from Halobacterium (an archaeon), Nostoc and Synechococcus (cyanobacteria) and Phytophthora (a stramenophile eukaryote). These appear to be members of the haloacid dehalogenase (HAD) superfamily of aspartate-nucleophile hydrolases by general homology and the conservation of all of the recognised catalytic motifs. The variable domain is found in between motifs 1 and 2, indicating membership in subfamily I and phylogeny and prediction of the alpha helical nature of the variable domain (by PSI-PRED) indicating membership in subfamily IA.</p> HAD-superfamily hydrolase, subfamily IA, hypothetical 1