Endoribonuclease L-PSP/chorismate mutase-like (IPR013813)

Short name: Endoribo_LPSP/chorism_mut-like

Overlapping homologous superfamilies

Domain relationships



This entry represents the beta-alpha-beta-alpha-beta(2) domains common both to bacterial chorismate mutase and to members of the YjgF/Yer057p/UK114 family. These proteins form trimers with a three-fold symmetry with three closely-packed beta-sheets. The conserved domain is similar in structure to chorismate mutase but there is no sequence similarity and no functional connection. This domain homotrimerizes forming a distinct intersubunit cavity that may serve as a small molecule binding site [PMID: 14624641, PMID: 12777779, PMID: 17506874, PMID: 16323205].

Chorismate mutase (CM, EC: is an enzyme of the aromatic amino acid biosynthetic pathway that catalyses the reaction at the branch point of the pathway leading to the three aromatic amino acids, phenylalanine, tryptophan and tyrosine (chorismic acid is the last common intermediate, and CM leads to the L-phenylalanine/L-tyrosine branch). It is part of the shikimate pathway, which is present only in bacteria, fungi and plants. The structure of chorismate mutase enzymes from Bacillus subtilis [PMID: 10818343] and Thermus thermophilus have been solved and were shown to have a catalytic homotrimer, with the active sites being located at the subunit interfaces, where residues from two subunits contribute to each site.

The YjgF/YER057c/UK114 family is a large, highly conserved, and widely distributed family of proteins found in bacteria, archaea and eukaryotes [PMID: 22094463]. YjgF (renamed RidA) deaminates reactive enamine/imine intermediates of pyridoxal 5'-phosphate (PLP)-dependent enzyme reactions. The YjgF/YER057c/UK114 family of proteins is conserved in all domains of life suggesting that reactive enamine/imine metabolites are of concern to all organisms [PMID: 22094463]. This family includes:

  • YjgF (RidA) [PMID: 18296521]
  • the yeast growth inhibitor YER057c (protein HMF1) that appears to play a role in the regulation of metabolic pathways and cell differentiation [PMID: 11442631]
  • the mammalian 14.5 kDa translational inhibitor protein UK114, also known as L-PSP (liver perchloric acid-soluble protein), with endoribonucleolytic activity that directly affects mRNA translation and can induce disaggregation of the reticulocyte polysomes into 80 S ribosomes [PMID: 10400702]
  • RutC from E. coli, which is essential for growth on uracil as sole nitrogen source and is thought to reduce aminoacrylate peracid to aminoacrylate [PMID: 20400551]
  • YabJ from B. subtilis, which is required for adenine-mediated repression of purine biosynthetic genes [PMID: 10557275]
Structurally these proteins are homotrimers with clefts between the monomeric subunits that are proposed to have some functional relevance [PMID: 19899170, PMID: 12112709, PMID: 10595546].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
  • cd02199 (YjgF_YER057c_UK114_like_1)