Homologous Superfamily

Ribosomal protein S5 domain 2-type fold (IPR020568)

Short name: Ribosomal_S5_D2-typ_fold

Overlapping entries



Domain 2 of the ribosomal protein S5 has a left-handed, 2-layer alpha/beta fold with a core structure consisting of beta(3)-alpha-beta-alpha. Domains with this fold are found in numerous RNA/DNA-binding proteins, as well as in kinases from the GHMP kinase family. Proteins containing this alpha/beta fold domain include:

  • Translational machinery components (ribosomal proteins S5 and S9, and domain IV of elongation factors EF-G and eEF-2) [PMID: 8722013].
  • Ribonuclease P protein (RNase P) [PMID: 17081993].
  • Ribonuclease PH (domain 1) [PMID: 14767080], as well as various exosome complex exonucleases (RRP41, RRP42, RRP43, RRP45, RRP46, MTR3, ECX1, ECX2) [PMID: 17174896].
  • DNA modification proteins (DNA mismatch repair proteins MutL and PMS2, DNA gyrase B, DNA topoisomerase II, IV-B and VI-B) [PMID: 11574484].
  • GHMP kinases that transfer a phosphoryl group from ATP to an acceptor (galactokinase (EC:, homoserine kinase (EC:, and mevalonate kinase (EC: [PMID: 15544330, PMID: 11188689].
  • Caenorhabditis elegans early switch protein Xol-1 (a divergent member of the GHMP kinase family that has lost the ATP-binding site) [PMID: 12672694].
  • Hsp90 chaperone (middle domain), which is related to the DNA gyrase/MutL family [PMID: 15039704]; this domain contains an extra C-terminal alpha/beta subdomain.
  • Imidazole glycerol phosphate dehydratase, which contains a duplication consisting of two structural repeats of this fold [PMID: 14724278].
  • The catalytic domain of ATP-dependent protease Lon (La), which contains an extra C-terminal alpha/beta subdomain [PMID: 14665623].
  • Formaldehyde-activating enzyme FAE, which contains a modification of this fold consisting of an extra alpha/beta unit after strand 2 [PMID: 15632161].

Contributing signatures

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