clpX

Summary

Gene Symbol: clpX
Description: ATPase and specificity subunit of ClpX-ClpP ATP-dependent serine protease
Alias: ECK0432, JW0428, lopC
Species: Escherichia coli str. K-12 substr. MG1655
Products:     clpX

Top Publications

  1. Kenniston J, Baker T, Sauer R. Partitioning between unfolding and release of native domains during ClpXP degradation determines substrate selectivity and partial processing. Proc Natl Acad Sci U S A. 2005;102:1390-5 pubmed
    ..This mechanism prevents trapping of the enzyme in futile degradation attempts and ensures that the energy of ATP hydrolysis is used efficiently for protein degradation. ..
  2. Siddiqui S, Sauer R, Baker T. Role of the processing pore of the ClpX AAA+ ATPase in the recognition and engagement of specific protein substrates. Genes Dev. 2004;18:369-74 pubmed
    b>ClpX binds substrates bearing specific classes of peptide signals, denatures these proteins, and translocates them through a central pore into ClpP for degradation...
  3. Martin A, Baker T, Sauer R. Protein unfolding by a AAA+ protease is dependent on ATP-hydrolysis rates and substrate energy landscapes. Nat Struct Mol Biol. 2008;15:139-45 pubmed publisher
    In the AAA+ ClpXP protease, repetitive cycles of ATP hydrolysis by ClpX unfold ssrA-tagged substrates, which are unraveled vectorially starting at the C-terminal tag and translocated into ClpP for degradation...
  4. Martin A, Baker T, Sauer R. Distinct static and dynamic interactions control ATPase-peptidase communication in a AAA+ protease. Mol Cell. 2007;27:41-52 pubmed
    In the ClpXP proteolytic machine, ClpX uses the energy of ATP hydrolysis to unfold protein substrates and translocate them through a central pore and into the degradation chamber of ClpP...
  5. Joshi S, Hersch G, Baker T, Sauer R. Communication between ClpX and ClpP during substrate processing and degradation. Nat Struct Mol Biol. 2004;11:404-11 pubmed
    In the ClpXP compartmental protease, ring hexamers of the AAA(+) ClpX ATPase bind, denature and then translocate protein substrates into the degradation chamber of the double-ring ClpP(14) peptidase...
  6. Martin A, Baker T, Sauer R. Diverse pore loops of the AAA+ ClpX machine mediate unassisted and adaptor-dependent recognition of ssrA-tagged substrates. Mol Cell. 2008;29:441-50 pubmed publisher
    b>ClpX, an archetypal proteolytic AAA+ unfoldase, must engage the ssrA tags of appropriate substrates prior to ATP-dependent unfolding and translocation of the denatured polypeptide into ClpP for degradation...
  7. Hersch G, Burton R, Bolon D, Baker T, Sauer R. Asymmetric interactions of ATP with the AAA+ ClpX6 unfoldase: allosteric control of a protein machine. Cell. 2005;121:1017-27 pubmed
    ATP hydrolysis by AAA+ ClpX hexamers powers protein unfolding and translocation during ClpXP degradation...
  8. Lehnherr H, Yarmolinsky M. Addiction protein Phd of plasmid prophage P1 is a substrate of the ClpXP serine protease of Escherichia coli. Proc Natl Acad Sci U S A. 1995;92:3274-7 pubmed
    ..This conclusion situates P1 among plasmids that elicit severe withdrawal symptoms and are able to do so because they encode both a cell toxin and an actively degraded macromolecule that blocks the synthesis or function of the toxin...
  9. Levchenko I, Seidel M, Sauer R, Baker T. A specificity-enhancing factor for the ClpXP degradation machine. Science. 2000;289:2354-6 pubmed
    ..Cells with an sspB mutation are defective in degrading ssrA-tagged proteins, demonstrating that SspB is a specificity-enhancing factor for ClpXP that controls substrate choice...

More Information

Publications93

  1. Camberg J, Hoskins J, Wickner S. The interplay of ClpXP with the cell division machinery in Escherichia coli. J Bacteriol. 2011;193:1911-8 pubmed publisher
    ClpXP is a two-component protease composed of ClpX, an ATP-dependent chaperone that recognizes and unfolds specific substrates, and ClpP, a serine protease...
  2. Wojtkowiak D, Georgopoulos C, Zylicz M. Isolation and characterization of ClpX, a new ATP-dependent specificity component of the Clp protease of Escherichia coli. J Biol Chem. 1993;268:22609-17 pubmed
    ..The second 46,000-Da component was identified as ClpX (LopC), coded by a gene located in the same operon, but promoter distal to that coding for ClpP (Gottesman, S...
  3. Slominska M, Wahl A, Wegrzyn G, Skarstad K. Degradation of mutant initiator protein DnaA204 by proteases ClpP, ClpQ and Lon is prevented when DNA is SeqA-free. Biochem J. 2003;370:867-71 pubmed
    ..The protein was stabilized by the presence of the chaperones ClpA and ClpX and degraded by their cognate protease ClpP...
  4. McGinness K, Baker T, Sauer R. Engineering controllable protein degradation. Mol Cell. 2006;22:701-7 pubmed
  5. Li C, Tao Y, Simon L. Expression of different-size transcripts from the clpP-clpX operon of Escherichia coli during carbon deprivation. J Bacteriol. 2000;182:6630-7 pubmed
    Transcription of the clpP-clpX operon of Escherichia coli leads to the production of two different sizes of transcripts. In log phase, the level of the longer transcript is higher than the level of the shorter transcript...
  6. Ades S. AAA+ molecular machines: firing on all cylinders. Curr Biol. 2006;16:R46-8 pubmed
  7. Mettert E, Kiley P. ClpXP-dependent proteolysis of FNR upon loss of its O2-sensing [4Fe-4S] cluster. J Mol Biol. 2005;354:220-32 pubmed
    ..on the ClpXP protease and required the presence of two amino acid sequences within FNR that resemble known ClpX recognition motifs...
  8. Makovets S, Powell L, Titheradge A, Blakely G, Murray N. Is modification sufficient to protect a bacterial chromosome from a resident restriction endonuclease?. Mol Microbiol. 2004;51:135-47 pubmed
    ..In the absence of efficient restriction alleviation, a Type I restriction enzyme cleaves host DNA and, under these conditions, homologous recombination maintains the integrity of the bacterial chromosome. ..
  9. Burston S. Anything a ClpA can do, two ClpAs can do better. Structure. 2009;17:483-4 pubmed publisher
  10. Koodathingal P, Jaffe N, Kraut D, Prakash S, Fishbain S, Herman C, et al. ATP-dependent proteases differ substantially in their ability to unfold globular proteins. J Biol Chem. 2009;284:18674-84 pubmed publisher
    ..We propose that these differences in unfolding abilities contribute to the fates of substrate proteins and may act as a further layer of selectivity during protein destruction. ..
  11. Glynn S, Martin A, Nager A, Baker T, Sauer R. Structures of asymmetric ClpX hexamers reveal nucleotide-dependent motions in a AAA+ protein-unfolding machine. Cell. 2009;139:744-56 pubmed publisher
    b>ClpX is a AAA+ machine that uses the energy of ATP binding and hydrolysis to unfold native proteins and translocate unfolded polypeptides into the ClpP peptidase...
  12. Maillard R, Chistol G, Sen M, Righini M, Tan J, Kaiser C, et al. ClpX(P) generates mechanical force to unfold and translocate its protein substrates. Cell. 2011;145:459-69 pubmed publisher
    ..We report direct observations of mechanical, force-induced protein unfolding by the ClpX unfoldase from E. coli, alone, and in complex with the ClpP peptidase...
  13. Maurizi M, Clark W, Katayama Y, Rudikoff S, Pumphrey J, Bowers B, et al. Sequence and structure of Clp P, the proteolytic component of the ATP-dependent Clp protease of Escherichia coli. J Biol Chem. 1990;265:12536-45 pubmed
    ..Mutations in clpP stabilize the same Clp A-beta-galactosidase fusion protein specifically stabilized by clpA mutations, providing the first genetic evidence that Clp A and Clp P act together in vivo. ..
  14. Smith C, Baker T, Sauer R. Lon and Clp family proteases and chaperones share homologous substrate-recognition domains. Proc Natl Acad Sci U S A. 1999;96:6678-82 pubmed
    ..The corresponding regions from ClpB and ClpX are unstable...
  15. Inobe T, Kraut D, Matouschek A. How to pick a protein and pull at it. Nat Struct Mol Biol. 2008;15:1135-6 pubmed publisher
  16. Pruteanu M, Baker T. Proteolysis in the SOS response and metal homeostasis in Escherichia coli. Res Microbiol. 2009;160:677-83 pubmed publisher
  17. Kruklitis R, Welty D, Nakai H. ClpX protein of Escherichia coli activates bacteriophage Mu transposase in the strand transfer complex for initiation of Mu DNA synthesis. EMBO J. 1996;15:935-44 pubmed
    ..Escherichia coli ClpX protein, a molecular chaperone, is a component required for MRFalpha activity, which removes MuA from DNA for the ..
  18. Blakely G, Murray N. Control of the endonuclease activity of type I restriction-modification systems is required to maintain chromosome integrity following homologous recombination. Mol Microbiol. 2006;60:883-93 pubmed
    ..coli K-12. Previously, the potential of the second pathway has only been demonstrated when expression of lar has been elevated. Our data identify the effect of lar from the repressed prophage. ..
  19. Moore S, Baker T, Sauer R. Forced extraction of targeted components from complex macromolecular assemblies. Proc Natl Acad Sci U S A. 2008;105:11685-90 pubmed publisher
    ..Forced extraction using AAA+ enzymes and targeted component proteins should be broadly applicable to the study of macromolecular complexes. ..
  20. Gonciarz Swiatek M, Wawrzynow A, Um S, Learn B, McMacken R, Kelley W, et al. Recognition, targeting, and hydrolysis of the lambda O replication protein by the ClpP/ClpX protease. J Biol Chem. 1999;274:13999-4005 pubmed
    ..that sequences at the C termini of polypeptide substrates are critical for efficient hydrolysis by the ClpP/ClpX ATP-dependent protease...
  21. Bougdour A, Cunning C, Baptiste P, Elliott T, Gottesman S. Multiple pathways for regulation of sigmaS (RpoS) stability in Escherichia coli via the action of multiple anti-adaptors. Mol Microbiol. 2008;68:298-313 pubmed
    ..Our results reveal that multiple anti-adaptor proteins allow the regulation of sigmaS stability through the regulation of RssB activity under a variety of stress conditions...
  22. Singh S, Rozycki J, Ortega J, Ishikawa T, Lo J, Steven A, et al. Functional domains of the ClpA and ClpX molecular chaperones identified by limited proteolysis and deletion analysis. J Biol Chem. 2001;276:29420-9 pubmed
    Escherichia coli ClpA and ClpX are ATP-dependent protein unfoldases that each interact with the protease, ClpP, to promote specific protein degradation...
  23. Ortega J, Lee H, Maurizi M, Steven A. ClpA and ClpX ATPases bind simultaneously to opposite ends of ClpP peptidase to form active hybrid complexes. J Struct Biol. 2004;146:217-26 pubmed
    ..are composed of a single proteolytic component, ClpP, complexed with either of the two related chaperones, ClpA or ClpX. ClpXP and ClpAP complexes interact with different specific substrates and catalyze ATP-dependent protein unfolding ..
  24. Schweder T, Lee K, Lomovskaya O, Matin A. Regulation of Escherichia coli starvation sigma factor (sigma s) by ClpXP protease. J Bacteriol. 1996;178:470-6 pubmed
    ..immunoblot analysis showed that in mutants lacking the protease ClpP or its cognate ATPase-containing subunit ClpX, sigma s levels of exponential-phase cells increased to those of stationary-phase wild-type cells...
  25. Stinson B, Nager A, Glynn S, Schmitz K, Baker T, Sauer R. Nucleotide binding and conformational switching in the hexameric ring of a AAA+ machine. Cell. 2013;153:628-39 pubmed publisher
    b>ClpX, a AAA+ ring homohexamer, uses the energy of ATP binding and hydrolysis to power conformational changes that unfold and translocate target proteins into the ClpP peptidase for degradation...
  26. Wojtyra U, Thibault G, Tuite A, Houry W. The N-terminal zinc binding domain of ClpX is a dimerization domain that modulates the chaperone function. J Biol Chem. 2003;278:48981-90 pubmed
    ..The mechanism by which this occurs is poorly understood. Here we demonstrate that the N-terminal domain of ClpX is a C4-type zinc binding domain (ZBD) involved in substrate recognition...
  27. Flynn J, Neher S, Kim Y, Sauer R, Baker T. Proteomic discovery of cellular substrates of the ClpXP protease reveals five classes of ClpX-recognition signals. Mol Cell. 2003;11:671-83 pubmed
    ..These results represent a description of general rules governing substrate recognition by a AAA+ family ATPase and suggest strategies for regulation of protein degradation. ..
  28. Ling L, Montaño S, Sauer R, Rice P, Baker T. Deciphering the Roles of Multicomponent Recognition Signals by the AAA+ Unfoldase ClpX. J Mol Biol. 2015;427:2966-82 pubmed publisher
    ..Here, we use the well-studied AAA+ unfoldase-substrate pair, Escherichia coli ClpX and MuA transposase, to address how these powerful enzymes recognize target protein complexes...
  29. Abdelhakim A, Oakes E, Sauer R, Baker T. Unique contacts direct high-priority recognition of the tetrameric Mu transposase-DNA complex by the AAA+ unfoldase ClpX. Mol Cell. 2008;30:39-50 pubmed publisher
    ..We explore how substrate multimerization modulates recognition by the ClpX unfoldase using a natural substrate, MuA transposase...
  30. Fredriksson A, Ballesteros M, Peterson C, Persson O, Silhavy T, Nystrom T. Decline in ribosomal fidelity contributes to the accumulation and stabilization of the master stress response regulator sigmaS upon carbon starvation. Genes Dev. 2007;21:862-74 pubmed
    ..We present a model for the sequence of events leading to the accumulation and activation of sigma(S) upon carbon starvation, which are linked to alterations in both ribosomal fidelity and efficiency. ..
  31. Zavigel skiÄ­ G, Kotova V, Mel kina O, PustovoÄ­t K. [Antirestriction activity of the mercury resistance nonconjugative transposon Tn5053 is controlled by the protease ClpXP]. Genetika. 2014;50:1033-9 pubmed
    ..coli K12 strains with the mutant genes clpX, clpP, and recA. The antirestriction effect of Tn5053 is not enhanced by 2-aminopurine...
  32. Neher S, Sauer R, Baker T. Distinct peptide signals in the UmuD and UmuD' subunits of UmuD/D' mediate tethering and substrate processing by the ClpXP protease. Proc Natl Acad Sci U S A. 2003;100:13219-24 pubmed
    ..UmuD resembles SspB, a well-characterized substrate-delivery protein for ClpX, in that both proteins use related peptide motifs to bind to the N-terminal domain of ClpX, thereby tethering ..
  33. Mhammedi Alaoui A, Pato M, Gama M, Toussaint A. A new component of bacteriophage Mu replicative transposition machinery: the Escherichia coli ClpX protein. Mol Microbiol. 1994;11:1109-16 pubmed
    ..Recently, a new potential ClpP associated ATPase, ClpX, has been described. We show here that this new subunit is required for Mu vir repressor degradation...
  34. Tomoyasu T, Mogk A, Langen H, Goloubinoff P, Bukau B. Genetic dissection of the roles of chaperones and proteases in protein folding and degradation in the Escherichia coli cytosol. Mol Microbiol. 2001;40:397-413 pubmed
    ..At 42 degrees C, ClpXP and Lon became essential for viability of cells with low DnaK levels, indicating synergistic action of proteases and the DnaK system, which is essential for cell growth at 42 degrees C. ..
  35. Hersch G, Baker T, Sauer R. SspB delivery of substrates for ClpXP proteolysis probed by the design of improved degradation tags. Proc Natl Acad Sci U S A. 2004;101:12136-41 pubmed
    The ssrA-degradation tag sequence contains contiguous binding sites for the SspB adaptor and the ClpX component of the ClpXP protease...
  36. Maglica Z, Kolygo K, Weber Ban E. Optimal efficiency of ClpAP and ClpXP chaperone-proteases is achieved by architectural symmetry. Structure. 2009;17:508-16 pubmed publisher
    ..We generated asymmetric ClpP particles in which the two rings differ in ClpA and ClpX binding capability and/or in proteolytic activity...
  37. Ortega J, Singh S, Ishikawa T, Maurizi M, Steven A. Visualization of substrate binding and translocation by the ATP-dependent protease, ClpXP. Mol Cell. 2000;6:1515-21 pubmed
    ..In sideviews of ATP gamma S-stabilized ClpXP complexes, a narrow axial channel was visible in ClpX, surrounded by protrusions on its distal surface...
  38. Chowdhury T, Chien P, Ebrahim S, Sauer R, Baker T. Versatile modes of peptide recognition by the ClpX N domain mediate alternative adaptor-binding specificities in different bacterial species. Protein Sci. 2010;19:242-54 pubmed publisher
    ..The N-terminal domain of the ClpX component of ClpXP is involved in recognition of many protein substrates, either directly or by binding the SspB ..
  39. Szalewska A, Wegrzyn G, Taylor K. Neither absence nor excess of lambda O initiator-digesting ClpXP protease affects lambda plasmid or phage replication in Escherichia coli. Mol Microbiol. 1994;13:469-74 pubmed
    ..Transcriptional activation of ori lambda, probably assisted by the Escherichia coli DnaA function, remains as the possible rate-limiting step in lambda DNA replication. ..
  40. Hoskins J, Yanagihara K, Mizuuchi K, Wickner S. ClpAP and ClpXP degrade proteins with tags located in the interior of the primary sequence. Proc Natl Acad Sci U S A. 2002;99:11037-42 pubmed
    ..We tested whether or not ClpA and ClpX can recognize tags when they are located in the interior of the primary sequence of the substrate...
  41. Levchenko I, Luo L, Baker T. Disassembly of the Mu transposase tetramer by the ClpX chaperone. Genes Dev. 1995;9:2399-408 pubmed
    ..Here we purify the Escherichia coli ClpX protein, a member of a family of multimeric ATPases present in prokaryotes and eukaryotes (the Clp family), on the ..
  42. Park E, Song H. A degradation signal recognition in prokaryotes. J Synchrotron Radiat. 2008;15:246-9 pubmed publisher
    ..composed of a compact ssrA-binding domain, which has a dimerization surface and a flexible C-terminal tail with a ClpX-binding motif at its very end...
  43. Spector S, Flynn J, Tidor B, Baker T, Sauer R. Expression of N-formylated proteins in Escherichia coli. Protein Expr Purif. 2003;32:317-22 pubmed
  44. Wah D, Levchenko I, Rieckhof G, Bolon D, Baker T, Sauer R. Flexible linkers leash the substrate binding domain of SspB to a peptide module that stabilizes delivery complexes with the AAA+ ClpXP protease. Mol Cell. 2003;12:355-63 pubmed
    ..A synthetic peptide containing the 10 C-terminal residues of SspB binds ClpX, stimulates its ATPase activity, and prevents SspB-mediated delivery of GFP-ssrA for ClpXP degradation...
  45. Muffler A, Fischer D, Altuvia S, Storz G, Hengge Aronis R. The response regulator RssB controls stability of the sigma(S) subunit of RNA polymerase in Escherichia coli. EMBO J. 1996;15:1333-9 pubmed
    ..RssB contains a unique C-terminal output domain and is the first known response regulator involved in the control of protein turnover. ..
  46. Donaldson L, Wojtyra U, Houry W. Solution structure of the dimeric zinc binding domain of the chaperone ClpX. J Biol Chem. 2003;278:48991-6 pubmed
    b>ClpX (423 amino acids), a member of the Clp/Hsp100 family of molecular chaperones and the protease, ClpP, comprise a multimeric complex supporting targeted protein degradation in Escherichia coli...
  47. Camberg J, Hoskins J, Wickner S. ClpXP protease degrades the cytoskeletal protein, FtsZ, and modulates FtsZ polymer dynamics. Proc Natl Acad Sci U S A. 2009;106:10614-9 pubmed publisher
    ..Deletion analysis shows that the N-terminal domain of ClpX is important for polymer recognition and that the FtsZ C terminus contains a ClpX recognition signal...
  48. Konieczny I, Helinski D. The replication initiation protein of the broad-host-range plasmid RK2 is activated by the ClpX chaperone. Proc Natl Acad Sci U S A. 1997;94:14378-82 pubmed
    ..However, preincubation of the TrfA protein with the ClpX molecular chaperone isolated from Escherichia coli activates the initiator protein for replication in the purified ..
  49. Fredriksson A, Nystrom T. Conditional and replicative senescence in Escherichia coli. Curr Opin Microbiol. 2006;9:612-8 pubmed
    ..Thus, bacterial physiology might entail both conditional and mandatory aging processes. ..
  50. Grimaud R, Kessel M, Beuron F, Steven A, Maurizi M. Enzymatic and structural similarities between the Escherichia coli ATP-dependent proteases, ClpXP and ClpAP. J Biol Chem. 1998;273:12476-81 pubmed
    Escherichia coli ClpX, a member of the Clp family of ATPases, has ATP-dependent chaperone activity and is required for specific ATP-dependent proteolytic activities expressed by ClpP...
  51. Bolon D, Grant R, Baker T, Sauer R. Nucleotide-dependent substrate handoff from the SspB adaptor to the AAA+ ClpXP protease. Mol Cell. 2004;16:343-50 pubmed publisher
    The SspB adaptor enhances ClpXP degradation by binding the ssrA degradation tag of substrates and the AAA+ ClpX unfoldase...
  52. Sharma S, Hoskins J, Wickner S. Binding and degradation of heterodimeric substrates by ClpAP and ClpXP. J Biol Chem. 2005;280:5449-55 pubmed
    ClpA and ClpX function both as molecular chaperones and as the regulatory components of ClpAP and ClpXP proteases, respectively...
  53. Jones J, Welty D, Nakai H. Versatile action of Escherichia coli ClpXP as protease or molecular chaperone for bacteriophage Mu transposition. J Biol Chem. 1998;273:459-65 pubmed
    The molecular chaperone ClpX of Escherichia coli plays two distinct functions for bacteriophage Mu DNA replication by transposition...
  54. O Neill M, Powell L, Murray N. Target recognition by EcoKI: the recognition domain is robust and restriction-deficiency commonly results from the proteolytic control of enzyme activity. J Mol Biol. 2001;307:951-63 pubmed
    ..Conversely, the viability of ClpX(-) r(-)m(-) bacteria can be used as evidence for little, or no, endonuclease activity...
  55. Kim Y, Burton R, Burton B, Sauer R, Baker T. Dynamics of substrate denaturation and translocation by the ClpXP degradation machine. Mol Cell. 2000;5:639-48 pubmed
    ClpXP is a protein machine composed of the ClpX ATPase, a member of the Clp/Hsp100 family of remodeling enzymes, and the ClpP peptidase. Here, ClpX and ClpXP are shown to catalyze denaturation of GFP modified with an ssrA degradation tag...
  56. Houry W. Chaperone-assisted protein folding in the cell cytoplasm. Curr Protein Pept Sci. 2001;2:227-44 pubmed
    ..Several advances have recently been made in characterizing the structure and function of all of these chaperone systems. These advances have provided us with a better understanding of the protein folding process in the cell. ..
  57. Levchenko I, Smith C, Walsh N, Sauer R, Baker T. PDZ-like domains mediate binding specificity in the Clp/Hsp100 family of chaperones and protease regulatory subunits. Cell. 1997;91:939-47 pubmed
    b>ClpX, a molecular chaperone and the regulatory subunit of the ClpXP protease, is shown to contain tandem modular domains that bind to the C-terminal sequences of target proteins in a manner that parallels functional specificity...
  58. Lamrani S, Ranquet C, Gama M, Nakai H, Shapiro J, Toussaint A, et al. Starvation-induced Mucts62-mediated coding sequence fusion: a role for ClpXP, Lon, RpoS and Crp. Mol Microbiol. 1999;32:327-43 pubmed
  59. Kim Y, Levchenko I, Fraczkowska K, Woodruff R, Sauer R, Baker T. Molecular determinants of complex formation between Clp/Hsp100 ATPases and the ClpP peptidase. Nat Struct Biol. 2001;8:230-3 pubmed
    ..In Escherichia coli, for instance, the ClpXP protease is assembled from the ClpX ATPase and the ClpP peptidase. Here, we have used multiple sequence alignments to identify a tripeptide 'IGF' in E...
  60. Yoo S, Seol J, Kang M, Ha D, Chung C. clpX encoding an alternative ATP-binding subunit of protease Ti (Clp) can be expressed independently from clpP in Escherichia coli. Biochem Biophys Res Commun. 1994;203:798-804 pubmed
    b>ClpX, an alternative ATP-binding subunit for protease Ti (also called Clp), has been shown to support the ATP-dependent hydrolysis of lambda O-protein by ClpP...
  61. Kwon A, Trame C, McKay D. Kinetics of protein substrate degradation by HslUV. J Struct Biol. 2004;146:141-7 pubmed
    ..mechanism of the apparent rate-limiting steps of unfolding and translocation by the chaperone components HslU and ClpX. The fall-off in degradation by HslUV for the more stable substrates that are degraded by ClpXP is consistent with ..
  62. Kenniston J, Burton R, Siddiqui S, Baker T, Sauer R. Effects of local protein stability and the geometric position of the substrate degradation tag on the efficiency of ClpXP denaturation and degradation. J Struct Biol. 2004;146:130-40 pubmed
    b>ClpX and related AAA+ ATPases of the Clp/Hsp100 family are able to denature native proteins...
  63. Wawrzynow A, Wojtkowiak D, Marszalek J, Banecki B, Jonsen M, Graves B, et al. The ClpX heat-shock protein of Escherichia coli, the ATP-dependent substrate specificity component of the ClpP-ClpX protease, is a novel molecular chaperone. EMBO J. 1995;14:1867-77 pubmed
    ..Previously, we identified the ClpX heat-shock protein of E...
  64. Welty D, Jones J, Nakai H. Communication of ClpXP protease hypersensitivity to bacteriophage Mu repressor isoforms. J Mol Biol. 1997;272:31-41 pubmed
  65. Schmidt R, Bukau B, Mogk A. Principles of general and regulatory proteolysis by AAA+ proteases in Escherichia coli. Res Microbiol. 2009;160:629-36 pubmed publisher
    ..Here we summarize the various strategies that tightly control substrate degradation from both sides: the generation of accessible degrons and their specific recognition by AAA+ proteases and cognate adaptor proteins. ..
  66. Martin A, Baker T, Sauer R. Pore loops of the AAA+ ClpX machine grip substrates to drive translocation and unfolding. Nat Struct Mol Biol. 2008;15:1147-51 pubmed publisher
    ..We show that a tyrosine residue in a pore loop of the hexameric ClpX unfoldase links ATP hydrolysis to mechanical work by gripping substrates during unfolding and translocation...
  67. Farrell C, Baker T, Sauer R. Altered specificity of a AAA+ protease. Mol Cell. 2007;25:161-6 pubmed
    ClpXP, an ATP-dependent protease, degrades hundreds of different intracellular proteins. ClpX chooses substrates by binding peptide tags, typically displayed at the N or C terminus of the protein to be degraded...
  68. Marshall Batty K, Nakai H. Activation of a dormant ClpX recognition motif of bacteriophage Mu repressor by inducing high local flexibility. J Biol Chem. 2008;283:9060-70 pubmed publisher
    ..Five residues at the Rep C terminus (CTD5) can serve as a ClpX recognition motif, but it is dormant unless activated, a state that can be induced by the presence of dominant-..
  69. Aertsen A, Vanoirbeek K, De Spiegeleer P, Sermon J, Hauben K, Farewell A, et al. Heat shock protein-mediated resistance to high hydrostatic pressure in Escherichia coli. Appl Environ Microbiol. 2004;70:2660-6 pubmed
    ..coli compared to wild-type levels. ..
  70. Banecki B, Wawrzynow A, Puzewicz J, Georgopoulos C, Zylicz M. Structure-function analysis of the zinc-binding region of the Clpx molecular chaperone. J Biol Chem. 2001;276:18843-8 pubmed
    The ClpX heat shock protein of Escherichia coli is a member of the universally conserved Hsp100 family of proteins, and possesses a putative zinc finger motif of the C(4) type...
  71. Zhou Y, Gottesman S, Hoskins J, Maurizi M, Wickner S. The RssB response regulator directly targets sigma(S) for degradation by ClpXP. Genes Dev. 2001;15:627-37 pubmed
    ..and RssB form a stable complex in the presence of acetyl phosphate, and together they form a ternary complex with ClpX that is stabilized by ATP[gamma-S]. Alone, neither sigma(S) nor RssB binds ClpX with high affinity...
  72. Wegrzyn A, Czyz A, Gabig M, Wegrzyn G. ClpP/ClpX-mediated degradation of the bacteriophage lambda O protein and regulation of lambda phage and lambda plasmid replication. Arch Microbiol. 2000;174:89-96 pubmed
    ..elements of the replication complex, in a free form is rapidly degraded in the host, Escherichia coli, by the ClpP/ClpX protease. Nevertheless, the physiological role of this rapid degradation remains unclear...
  73. Weichart D, Querfurth N, Dreger M, Hengge Aronis R. Global role for ClpP-containing proteases in stationary-phase adaptation of Escherichia coli. J Bacteriol. 2003;185:115-25 pubmed
    To elucidate the involvement of proteolysis in the regulation of stationary-phase adaptation, the clpA, clpX, and clpP protease mutants of Escherichia coli were subjected to proteome analysis during growth and during carbon starvation...
  74. Pierechod M, Nowak A, Saari A, Purta E, Bujnicki J, Konieczny I. Conformation of a plasmid replication initiator protein affects its proteolysis by ClpXP system. Protein Sci. 2009;18:637-49 pubmed publisher
    ..Our in vivo and in vitro experiments demonstrated that the ClpX-dependent activation of TrfA leading to replicationally active protein monomers and mutations affecting TrfA dimer ..
  75. Gottesman S, Roche E, Zhou Y, Sauer R. The ClpXP and ClpAP proteases degrade proteins with carboxy-terminal peptide tails added by the SsrA-tagging system. Genes Dev. 1998;12:1338-47 pubmed
    ..components and required a substrate with a wild-type SsrA tail, the presence of both ClpP and either ClpA or ClpX, and ATP...
  76. Wah D, Levchenko I, Baker T, Sauer R. Characterization of a specificity factor for an AAA+ ATPase: assembly of SspB dimers with ssrA-tagged proteins and the ClpX hexamer. Chem Biol. 2002;9:1237-45 pubmed
    ..SspB by itself binds to ClpX and stimulates the ATPase activity of this enzyme...
  77. Cheng L, Naumann T, Horswill A, Hong S, Venters B, Tomsho J, et al. Discovery of antibacterial cyclic peptides that inhibit the ClpXP protease. Protein Sci. 2007;16:1535-42 pubmed
    ..The screen used here could be adapted to identify cyclic peptide inhibitors of any enzyme that can be expressed in E. coli in conjunction with a fluorescent reporter. ..
  78. Ades S. Proteolysis: Adaptor, adaptor, catch me a catch. Curr Biol. 2004;14:R924-6 pubmed
    ..New work in Escherichia coli implicates adaptor proteins in enhancing substrate selectivity and regulating the flow of substrates to cellular proteases. ..
  79. Nagashima K, Kubota Y, Shibata T, Sakaguchi C, Shinagawa H, Hishida T. Degradation of Escherichia coli RecN aggregates by ClpXP protease and its implications for DNA damage tolerance. J Biol Chem. 2006;281:30941-6 pubmed
    ..These data demonstrate that ClpXP is a critical factor in the cellular clearance of cytoplasmic RecN aggregates from the cell and therefore plays an important role in DNA damage tolerance. ..
  80. Barkow S, Levchenko I, Baker T, Sauer R. Polypeptide translocation by the AAA+ ClpXP protease machine. Chem Biol. 2009;16:605-12 pubmed publisher
    In the AAA+ ClpXP protease, ClpX uses repeated cycles of ATP hydrolysis to pull native proteins apart and to translocate the denatured polypeptide into ClpP for degradation. Here, we probe polypeptide features important for translocation...
  81. Rami A, Toutain C, Jacq A. An increased level of alternative sigma factor RpoS partially suppresses drug hypersensitivity associated with inactivation of the multidrug resistance pump AcrAB in Escherichia coli. Res Microbiol. 2005;156:356-60 pubmed
  82. Bohn C, Binet E, Bouloc P. Screening for stabilization of proteins with a trans-translation signature in Escherichia coli selects for inactivation of the ClpXP protease. Mol Genet Genomics. 2002;266:827-31 pubmed
    ..Two screens were devised to identify insertional mutants that stabilize such substrates. Only disruption of the clpX or clpP gene resulted in stabilization of the tagged substrates...
  83. Ortega J, Lee H, Maurizi M, Steven A. Alternating translocation of protein substrates from both ends of ClpXP protease. EMBO J. 2002;21:4938-49 pubmed
    In ClpXP protease complexes, hexameric rings of the ATP-dependent ClpX chaperone stack on one or both faces of the double-heptameric rings of ClpP...
  84. Joshi S, Baker T, Sauer R. C-terminal domain mutations in ClpX uncouple substrate binding from an engagement step required for unfolding. Mol Microbiol. 2003;48:67-76 pubmed
    b>ClpX mediates ATP-dependent denaturation of specific target proteins and disassembly of protein complexes. Like other AAA + family members, ClpX contains an alphabeta ATPase domain and an alpha-helical C-terminal domain...