Phosphoesterase, HXTX (IPR014051)

Short name: Phosphoesterase_HXTX

Overlapping homologous superfamilies

Domain relationships



This entry represents a domain found in a number of known and predicted phosphoesterases. These include bacterial and archaeal 2',5' RNA ligases, and a family of predicted phosphoesterases known as the YjcG family. The 2',5' RNA ligases perform a reversible, ATP-independent 2'-5'-ligation of what is presumably a non-phyiological substrate: half-tRNA splice intermediates from an intron-containing yeast tRNA [PMID: 8940112]. The physiological substrate(s) in prokaryotes may include small 2',5'-link-containing oligonucleotides, perhaps with regulatory or biosynthetic roles. This domain contains a conserved HXTX motif which is thought to be important for catalytic activity, as it is in the related enzyme cyclic nucleotide phosphodiesterase (CPDase) [PMID: 12466548]. In 2',5' RNA ligase this domain is duplicated, with the two conserved motifs forming the proposed active site, which is analogous to that of CPDase [PMID: 12798681].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.