| Endopeptidase Clp | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 ATP-dependent Clp protease (fragment) homo14mer, Streptococcus pneumoniae | |||||||||
| Identifiers | |||||||||
| EC no. | 3.4.21.92 | ||||||||
| CAS no. | 110910-59-3 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDBPDBePDBsum | ||||||||
| |||||||||
Endopeptidase Clp (EC3.4.21.92,endopeptidase Ti,caseinolytic protease,protease Ti,ATP-dependent Clp protease,ClpP,Clp protease).[1][2][3][4] This enzymecatalyses the followingchemical reaction
This bacterial enzyme contains subunits of two types,ClpP, withpeptidase activity, and the protein ClpA, withAAA+ATPase activity. ClpP and ClpA are not evolutionarily related.
A fully assembled Clp protease complex has a barrel-shaped structure in which two stacked heptameric ring of proteolytic subunits (ClpP or ClpQ) are either sandwiched between two rings or single-caped by one ring of hexameric ATPase-activechaperon subunits (ClpA, ClpC, ClpE,ClpX, ClpY, or others).[5]
ClpXP is presented in almost all bacteria while ClpA is found in the Gram-negative bacteria, ClpC in Gram-Positive bacteria and cyanobacteria. ClpAP, ClpXP and ClpYQ coexist inE. coli while only ClpXP complex in present in humans as mitochondrial enzymes.[5] ClpYQ is another name for theHslVU complex, aheat shock protein complex thought to resemble the hypothetical ancestor of theproteasome.[6]
| ClpA/B | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| Symbol | ClpA/B | ||||||||
| Pfam | PF02861 | ||||||||
| InterPro | IPR001270 | ||||||||
| |||||||||
| ClpX | |
|---|---|
| Identifiers | |
| Symbol | ClpX |
| InterPro | IPR004487 |
TheHsp100 family of eukaryotic heat shock proteins is homologous to the ATPase-active chaperon subunits found in the Clp complex; as such the entire group is often referred to as theHSP100/Clp family. The family is usually broken into two parts, one being the ClpA/B family with two ATPase domains, and the other being ClpX and friends with only one such domain.[7] ClpA through E is put into the first group along with Hsp78/104, and ClpX and HSIU is put into the second group.[8]
Many of the proteins are not associated with a protease and have functions other than proteolysis. ClpB (humanCLPB "Hsp78", yeastHsp104) break up insoluble protein aggregates in conjunction with DnaK/Hsp70. They are thought to function by threading client proteins through a small 20 Å (2nm) pore, thereby giving each client protein a second chance to fold.[8][9][10] A member of the ClpA/B family termed ClpV is used in the bacterialT6SS.[11]
