Summary for clan SJ
| Clan type peptidase | S16.001 - Lon-A peptidase (Escherichia coli), MEROPS Accession MER0000485 (peptidase unit: 537-784); PDB accession 1RR9_A |
| History | MEROPS 6.6 (27 March 2004) |
| Description | Serine nucleophile; catalytic residues in the order Ser, Lys in sequence |
| Contents of clan | Clan SJ contains endopeptidases. |
| Evidence | The inclusion of family S50 within the clan is based on similar sequence motifs around the active site residues, Gly-Gln-Ser-Ala-Xaa-Xbb and Lys-Xbb-Xbb-Ala-Ala-His, where Xaa is a small amino acid and Xbb is an aliphatic hydrophobic residue (Birghan et al., 2000; see the Alignment). |
| Catalytic mechanism | There is a Ser, Lys catalytic dyad. The catalytic mechanism in family S16 has been discussed by Botos et al. (2004). |
| Peptidase activity | The enzymes are endopeptidases (see families S16 and S50). |
| Protein fold | Tertiary structures have only been determined for members of family S16 (endopeptidase La, S16.001; Botos et al., 2004). Endopeptidase La is an alpha/beta protein in which the secondary structure elements are in two layers, each with a beta sheet and helices. The active site lies between the layers. |
| Homologous non-peptidase families | The fold is similar to that of a number of nucleic acid-binding proteins, including DNA gyrase, ribonucleases P and PH, elongation factors G and 2, ribosomal proteins S5 and S9 and enzymes such as UDP-3-O-[3-hydroxymyristoyl] N-acetylglucosamine deacetylase LpxC and imidazole glycerol phosphate dehydratase (see SCOP sunid 54211). |
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Other databases
| SCOP | 54211 |
Families
| S16 |
Lon-A peptidase (Escherichia coli) |
Yes |
| S50 |
infectious pancreatic necrosis birnavirus Vp4 peptidase (infectious pancreatic necrosis virus) |
Yes |
| S69 |
Tellina virus 1 VP4 peptidase (Tellina virus 1) |
Yes |
Distribution of clan SJ among Kingdoms of Organisms
