Hydrolysis of proteins to small peptides in the presence of ATP and Mg2+.
This bacterial enzyme contains subunits of two types, ClpP, with peptidase activity, and the protein ClpA, with AAA+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-active chaperon 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 in E. coli while only ClpXP complex in present in humans as mitochondrial enzymes.[5] ClpYQ is another name for the HslVU complex, a heat shock protein complex thought to resemble the hypothetical ancestor of the proteasome.[6]
^Gottesman S, Clark WP, Maurizi MR (May 1990). "The ATP-dependent Clp protease of Escherichia coli. Sequence of clpA and identification of a Clp-specific substrate". The Journal of Biological Chemistry. 265 (14): 7886–93. PMID2186030.
^Maurizi MR, Clark WP, Katayama Y, Rudikoff S, Pumphrey J, Bowers B, Gottesman S (July 1990). "Sequence and structure of Clp P, the proteolytic component of the ATP-dependent Clp protease of Escherichia coli". The Journal of Biological Chemistry. 265 (21): 12536–45. PMID2197275.
^Maurizi MR, Thompson MW, Singh SK, Kim SH (1994). Endopeptidase Clp: ATP-dependent Clp protease from Escherichia coli. Methods in Enzymology. Vol. 244. pp. 314–31. doi:10.1016/0076-6879(94)44025-5. PMID7845217.
^ abHamon MP, Bulteau AL, Friguet B (September 2015). "Mitochondrial proteases and protein quality control in ageing and longevity". Ageing Research Reviews. 23 (Pt A): 56–66. doi:10.1016/j.arr.2014.12.010. PMID25578288. S2CID205667759.
^Gille C, Goede A, Schlöetelburg C, Preissner R, Kloetzel PM, Göbel UB, Frömmel C (March 2003). "A comprehensive view on proteasomal sequences: implications for the evolution of the proteasome". Journal of Molecular Biology. 326 (5): 1437–48. doi:10.1016/s0022-2836(02)01470-5. PMID12595256.