This entry represents the PP-loop motif superfamily [1,2]. The PP-loop motif appears to be a modified version of the P-loop of nucleotide binding domain that is involved in phosphate binding [3]. Named PP-motif, since it appears to be a part of a previously uncharacterised ATP pyrophophatase domain. ATP sulfurylases, Escherichia coli NtrL, and Bacillus subtilis OutB consist of this domain alone. In other proteins, the pyrophosphatase domain is associated with amidotransferase domains (type I or type II), a putative citrulline-aspartate ligase domain or a nitrilase/amidase domain.

1. A P-loop-like motif in a widespread ATP pyrophosphatase domain: implications for the evolution of sequence motifs and enzyme activity. Proteins 20, 347-55
2. Chemical modification and site-directed mutagenesis of conserved HXXH and PP-loop motif arginines and histidines in the murine bifunctional ATP sulfurylase/adenosine 5'-phosphosulfate kinase. J. Biol. Chem. 274, 28929-36

This entry represents the PP-loop motif superfamily [1,Show more...

Download genes (select columns to include)